eChapters

Abstract

Blumea lacera (Burm f.) DC. belonging to family Asteraceae is an annual herb with a strong odour. This herb is distributed throughout the plains of North-west India upto an elevation of 2,900 m and is also reported from Tropical Africa, South East Asia, Bangladesh, Nepal, Indonesia, Malaysia, Philippines, Thailand and Vietnam. Blumea lacera is a plant with camphor-like odour, and is highly variable, grows in grassland, field, roadside and forest edge. Traditionally, it is used internally and externally as a hemostatic and anti-inflammatory agent. The juice of leaves along with black pepper (Piper nigrum) is given to cure bleeding piles. This herb is also offered as anthelmintic (especially for threadworm). Leaves and roots are used as astringent, diuretic and febrifuge and even in cuts and wounds. Bruises and ulcers can also be treated by applying fresh juice or extract. For treating piles (Hemorrhoids), the leaves of B. lacera has been used in ethnomedicinal practices.The phytoconstituents present in leaves are mainly terpenoids, glycosides, volatile oils, some glycoalkaloids and many more yet to be determined. B. lacera has been used as an ingredient in many pharmaceutical preparations. The chapter gives a brief idea about the ethnomedicinal usage, phytochemical profile, pharmacological usage and the future perspective of B. lacera. and would help the researchers for better understanding of this plant as well as developing plant derived molecules in drug discovery process.

Abstract

The percentage of people with obesity and diabetes has increased globally both in developed and developing countries but highest burden is on the indigenous people who are also socially disadvantaged. The modern medical treatment of diabetes is based generally on oral hypoglycaemic agents and insulin. So, there has always been a search for new anti-diabetic agents which are of lower cost and can cure the disease without harming other body functions. Plants being readily available in the Indian-subcontinent have been an important source of drug in the traditional system of medicine in India since time immemorial. The utilization of plants for alternative treatment to combat diabetes using herbal remedies has also been substantiated by World Health Organization. In this communication, we tried to list some scientifically proven anti-diabetic plants commonly available in the Indian subcontinent which can be used in the treatment and management of diabetes.

Abstract

Wild plants have a great role in the lives of tribal peoples living in and around the world by way of providing products for both food and medicine. Such herbal plants are the core of research, which can solve several health issues as well as nutritional supplements. Keeping on the view we have presented a summary of medicinal plants used as nutraceuticals collected from various regions of India. This communication describes 35 herbal plants used as a medicine against different diseases as well as their nutritional applicability.

Abstract

For thousands of years, plants have provided medicine to human and animals. People still depend on plants for food and shelter. The present surveys and investigation covers Jasrota Wildlife Sanctuary, Kathua District (J&K) situated in Southeastern parts of Asia (India). This communication mainly focused on ten high value plant species belonging to eight families of medicinal value being used to cure different types of ailment growing in Jasrota Wildlife Sanctuary and surrounding areas of Kathua district. These species are Aerva sanguinolenta (L.) Blume, Centella asiatica L. (Urb.) Fl., Cissampelos pareira L., Colebrookea oppositifolia Sm., Cryptolepis dubia M.R.Almeida, Holarrhena pubescens Wall. ex G.Don, Justicia adhatoda L., Tinospora cordifolia (Willd.) Miers ex Hook.f. & Thomson, Vitex negundo L. and Woodfordia fruticosa (L.) Kurz. It also deal with morphological enumeration, ecology and habitat, ethnobotanical uses and active chemical constituent present in studied plant species.

Abstract

India harbors a wide variety of medicinal plants used traditionally in various remedies to treat livestock ailments. The therapeutic value of these plants attributes due to the concentration of several bioactive compounds present in them. Indigenous tribal communities are the treasurer of age-old traditional knowledge which inhabits Asian country since centuries. District Poonch exhibits a rich repository of traditional knowledge as major part of the population comprised of nomadic tribes such as Gujjars and Bakerwals which are still practicing the primitive traditional ways to treat diseases. In the present investigation, the traditional herbal plants and associated remedies for treatment of various veterinary disorders are presented. A total of 34 plant species belonging to 30 genera and 21 families have been reported which are being used by indigenous people for ethnoveterinary purposes. The majority of ethnoveterinary plants recorded from the district belong to families such as Ranunculaceae and Araceae (4 species each), Acoraceae, Amaryllidaceae, Apiaceae, Fagaceae, Lamiaceae, Primulaceae, Rutaceae (2 species each) and rest of the families members were represented by one species each. The frequently used plant parts are roots (30.23%), followed by tubers (18.6%), leaves (16.28%), fruits and whole plant (13.95% each), stems (4.65%) and seeds (2.33%). It has been observed that numerous formulations are made from these parts which are used for the treatment of various cattle infections such as abdominal colic, allergic infection, anestrous, chest diseases, constipation, cough, digestive troubles, FMD, fracture, galactagogue, gaseous bloat, induce puberty, internal injury, lung disease, pneumonia, quick discharge, removal of Leech, sexual stimulant, skin infection, snake-bite, stomachache and weakness with snake bite being dominant. The present study infers that the documentation of ethnoveterinary knowledge from the district requires utmost attention and may give leads or serves for further biochemical studies for the discovery of novel plant based drugs which will certainly helps in commercialization and betterment of tribals through benefit resource sharing.

Abstract

Ladakh, a geographically isolated region, is known for its tough terrain and harsh climatic conditions. It remains cut off from rest of the country for 6-7 months in a year during winters. With limited food, fuel and other resources the people here have developed and sustained a long unique relationship with plants. They have been using both cultivated and wild ones as medicine, food, and fodder since centuries. The local populace possesses good knowledge of traditional methods of utilization of plant resources for diverse purposes, which they have acquired from their ancestors. However, this indigenous knowledge and age old practices are fast disappearing from the tribal communities, and there is an urgent need to save this treasure from getting irretrievably lost. Therefore, the present study is an attempt to document the various wild and cultivated plants along with their ethnobotanical uses as per the ancient practices of these tribal communities. For this purpose, an ethnobotanical survey was conducted in various villages of lower Ladakh. The investigation revealed a host of plants put to use by the natives in different indigenous ways. The scientific, family and local names of 50 species belonging to 48 genera and 31 families along with their uses have been enlisted in the present communication. As per the information gathered from the local inhabitants, these plants are categorized into five different groups. More than 50% of these are used as medicines, 38% are edible, 24% as fuel and 20% as fodder. Approximately 38% plants are employed in construction, as ornamentals, or sources of dyes, incense, cosmetics, etc.

Abstract

Traditional knowledge on plants and their uses by tribal indigenous culture is helpful in the conservation of biodiversity. During 2017-2018, ethnobotanical investigations of the plants growing in Neelum Valley in District Bandipora (a part of Kashmir Himalaya) were carried out to collect information regarding different usages of the plants species growing in the region through questionnaire and interviews. Floristically, a total of 57 species belonging to 54 genera and 38 families were investigated to be used as medicine, food, fodder, timber, fuel wood, vegetable/edible fruit, resin yield and herbal tea purposes. On the basis of the floristic analysis of the study area, the leading family recorded was Asteraceae with (11%) species co-dominated by Rosaceae (9%). In terms of habit forms, herbaceous (70%) growth form is the most dominant. The most frequently used plant parts are leaves (26%) followed by whole plant (23%) and roots (19%). The plant documented cured different categories of diseases, the most common diseases such as diarrhea, fever, digestive problems, urinary troubles, rheumatism, eye diseases, skin diseases and wounds. Based on investigated knowledge, the data are discussed under sub-head as single, double and multi-diseases curing plants. The present study can provide a baseline data for future researchers, policy makers, common public, land managers, and the other stakeholders to develop scientifically-informed strategies for conservation of natural resources and sustainable use of plant resources in hotspot regions like Himalayas and other similar biodiversity rich sites.

Abstract

Family Apiaceae (or Umbelliferae) is one of the largest plant group represented by 418 genera and 3257 species (TPL 2013). The plants members are mostly aromatic, used by local populace as traditional medicines as well as spice and condiments in their routine food preparations. They have characteristic aroma due to the presence of some essential oils or oleoresin. Members of this family possess large number of compounds having antibacterial, hepato-protective, vaso-relaxant, inducing apoptosis and antitumor activities. Although the family is distributed globally but Indian subcontinent is a major center of its diversification, where more than 200 species are distributed specifically in the Himalayan eco-terrains. Jammu province (Jammu and Kashmir, India) in North Western Himalaya having unique climatic conditions supports a large variety of medicinal and aromatic plants, and amongst these Apiaceae are well known. Local people uses these plants as vegetables, for culinary purposes and valued as traditional medicine like Bunium persicum (black cumin), Carum carvi (caraway), Coriandrum sativum (coriander), Cuminum cyminum (cumin), Foeniculum vulgare (fennel), Narthex asafoetida (Heeng), Trachyspermum ammi (ajwain) and Centella asiatica (Brahmi). People in Jammu province have their unique traditional way of using plants, knowledge of which is being transferred from generation to generation through oral dialect. As the data on the numbers of Apiaceae is scattered in the literature and difficult to be procured by the researchers. Therefore the current attempt is made so that the data along with some quantitative statistics can be provided at one platform only.

Abstract

In developing countries, about 80 percent of the world population depends on traditional medicines for their primary healthcare as estimated by World Health Organization. In a recent floristic survey undertaken in Chithara Village Panchayat recorded a very rich diversity of wild medicinal plants. Based on extensive literature search, of the total 272 plants, 96% species were known to have marginal to outstanding medicinal properties and uses. Among the plants, ten species namely, Bacopa monnieri (L.) Wettst., Cannabis sativa L., Cissampelos pareira L., Coccinia grandis (L.) Voigt, Eclipta prostrata (L.) L., Euphorbia hirta L., Hyptis suaveolens (L.) Poit., Justicia adhatoda L., Solanum americanum Mill. and Withania somnifera (L.) Dunal were found to be very important as they possess medicinal properties for curing a large number of diseases in traditional system of medicines in India and other parts of the world. The whole plants including root, stem and leaves are utilized traditionally for curing various ailments such as abdominal pain, cold, cough, diarrhoea, dysentery, inflammation, fever, rheumatism, sexual disorders, skin diseases, respiratory diseases etc. These plants are also reported to contain numerous important phytochemicals such as alkanes, amino acids, flavonoids, organic acids, polyphenolic compounds, polyphenols, steroids, tannins, terpenes etc. which qualifies their various medicinal properties. Plants are reported to yield potent drug such as vasicine and vasicinone (by A. vasica), bacosoids (B. monnieri) and withanolides (W. somnifera). The paper provides the details of traditional medicinal usages and chemical constituents of ten high value medicinal plants recorded from the study area.

Abstract

Plants are an integral component of life in many ethnic communities. Plant-based medicaments have been used since time immemorial as curative and protective agents for prolonging life of humans and animals by combating a plethora of ailments. One such ailment affecting women of reproductive age-group is leucorrhea. The study aimed at systematically documenting the precious traditional knowledge regarding the plants traditionally used for curing leucorrhea in Jammu and Kashmir. A total of 55 infomants (39 females and 16 males) between the age group 25-94 years were selected and interviewed for extracting ethnomedicinal information and 29 plant species belonging to 28 genera and 23 families were observed to be of ethnomedicinal significance in the treatment of leucorrhea in Jammu and Kashmir. Fabaceae was observed to be the frequently encountered family. Bulk of the taxa were observed to grow in wild habitat and majority of them were herbs. Seeds were observed to be of highest therapeutic significance and ethnomedicinal formulations were prepared in the form of powder, decoction, paste, etc and all of these were administered orally. The present study may serve as a base line data for further research and will go a long way in the treatment of leucorrhea thereby promoting well being of women folk. Advanced investigations are required to validate the time-tested information associated with medicinal flora to determine the identity of phytochemicals linked with leucorrhea, so that compounds of pharmacological application having prospective relevance in the alleviation of human maladies may be discovered.

Abstract

Lichenized fungi or lichens represent the most successful symbiotic organisms on earth. They are the inconspicuous group of lower plants having numerous properties. Their different growth forms namely crustose, foliose and fruticose have been put to use in one way or the other. Since ancient times, they were used as food, fodder, dye and in perfumery. Lichens are a rich source of several important secondary metabolites because of which they are widely used as a source of medicine against several diseases and to improve the health of humans as well as animals. Most of the information related to the usage of lichens is gathered from the traditional knowledge holders. Therefore, there is a need to explore and document this traditional knowledge associated with lichens. The present paper thus makes an attempt to present and document the valued information on the ethnobiological uses of lichens from the Northwestern parts of the Himalayas, if not, the undocumented information will be lost for all the future generations. Ethnobiology of 39 species of lichens belonging to 08 families is being presented in this communication.

Abstract

Wild plants of medicinal value are the embodiment of knowledge perception gift from our ancestors and these plays a significant role in curing various human health disorders. This gifted knowledge of economic plants used by the local people usually has long narrations for use in their daily activities. Considering the value of indigenous knowledge associated with plants, a study was undertaken on herbaceous communities in Atraulia area (Burhanpur tehsil), district Azamgarh, Uttar Pradesh. During the investigation, a total of 71 informants (22 females and 49 males) were interviewed and data regarding ethnobotanical information on wild plant species were documented and analysed. The results indicated a total of 169 species belonging to 41 families used in indigenous herbal preparation as medicine from Atraulia area by local tribal people. The dominant growth forms were the annual herbs represented by 91 species, followed by 46 species of perennial nature and 32 species of biennial growth. Therefore, we can conclude that this region is rich in herbaceous plants and plant used as medicine is wide spread in the study area. This communication deals with demography of the informants, botanical name of herbaceous plants, family, part used, disease cure, use report, frequency of use and recommendation for conservation of unique valueable resources.

Abstract

Asteraceae is one of the largest family of flowering plants and have been used by mankind for a variety of purposes including food, medicine, cooking oils, sweeteners and tea infusions. In India, Asteraceae is 4^th largest family of angiosperms and ranked third among dominant families of angiosperms in Arunachal Pradesh. The indigenous communities of Arunachal Pradesh possess a rich knowledge on utilization of the plant resources around them for food, fodder, medicine and other purposes. Due to the remoteness and inaccessibility, the indigenous communities are mostly depended on their traditional medicines using plant resources around them for treating minor and major ailments. The effectiveness of these plants in traditional medicine has also been confirmed after isolation and characterization of the bioactive compounds responsible for their pharmacological activities. The present study is a review on ethnomedicinal plants belonging to Asteraceae family that are being used by different tribes of the state. The tribal communities have been using 36 medicinal plant species from this family as recorded from published literature and field study. Maximum number of species have been found to exhibit antimicrobial, antioxidant, antihelminthic, analgesic and anti-malarial properties. Among the recorded species, Ageratum conyzoides, Spilanthes acmella, Artemisia nilagirica, A. maritima, Blumea balsamifera, B. lacera, Eclipta prostrata, Vernonia cinerea and Chrysanthemum indicum were already being used in Ayurveda, Unani, Siddha, Homeopathy, Folk and Sowa-Rigpa systems of Indian Medicine. Therefore, the study highlighted the pharmacological potential of ethnomedicinal plantsfrom Asteraceae family which would provide opportunities for future drugdiscovery.

Abstract

Ethnobotany is the area of study which include direct interaction of human and plants. This communication compiles and evaluates 301 ethnobotanically important medicinal plants used by ethnic tribes for the treatment of different ailments living in Uttarakhand Himalaya. The state is a home of five major tribes, viz., Bhoxa, Bhotiya, Tharu, Raji, and Jaunsari. These tribal people have age-old relations with plants, and their indigenous knowledge passed from one generation to another. In this communication, a total of 90 plant families were reviewed and recorded that Asteraceae, Lamiaceae, Rosaceae, Fabaceae, Amaranthaceae Apiaceae, Combretaceae, Euphorbiaceae, Anacardiaceae and Malvaceae members are frequently used as medicinal plants. Total 68 roots of different species, followed by leaves of 55 species, whole plants of 29 species, fruits of 26 species and 28 types of seeds of different plants families used by locals for the treatment of various diseases such as fever, cold, cough, diabetes, skin problems, digestive problems and other associated ailments. The mode of application of herbal formulations varies from tribe to tribe. Herbaceous communities belonging to 160 species were the frequently used plant groups followed by trees, shrubs, and lianas. The decoction was recorded as the most frequently used method of preparation. Medicinal plants sold in the market was not primary for local people rather herbal plants locally available used as food, spice and beverages preparations. Therefore, there is a need for proper documentation and conservation planting of these unique medicinal plants growing in the Himalayas.

Abstract

The paper deals with taxonomy, ethnobotany and threat status of lesser known liana species Hodgsonia heteroclita (Roxb.) Hook.f. & Thomson. The local people use in terms of foods and rites and its role in ecosystem have been reported. Local people used the seeds of liana as food because of high nutritive value. Threat assessment has been following IUCN version 3.1 to evaluate the threat status of the species in Sikkim Himalaya. Out of the five criteria, data on two criteria could be collected and was used to evaluate the threat category of the species. The criteria used for threat assessment were (a) reduction in population and (b) geographical range in the form of either B1 (extent of occurrence) or B2 (area of occupancy) or both. Considering the population status and geographical range of the species, it has been classified as “Least Concern” (A1acd; B2ab(ii,iv)).

Abstract

The Khasi tribe of Meghalaya depends on wild medicinal plants for curing a number of ailments since ages. The traditional knowledge systems which evolved through trial and error method are an integral part of their culture. The objectives of the present study were to highlight the medicinal plants used by the Khasi tribe to treat various diseases, provide scientific validation of the medicinal plants by pharmacological screening using secondary literature and suggest strategies for its sustainable management. A total of 363 plants distributed in 283 genera and 129 families were documented. The life forms of these plants were in the order of herb > tree > shrub > climber > parasite > epiphyte. The herbal remedies for treating various ailments are prepared by using the whole plant either individually or in combination with other plant parts. Cross validation with the help of secondary literature showed the presence of active compounds in these plants. Therefore, it is suggested that traditional knowledge should be properly documented and scientifically explored with more emphasis on species specific phytochemicals and their mode of action.

Abstract

Since pre-historic times plants have tendered their services to mankind in the form of food, shelter and medicine. Due to the advancement of human civilization, various folklore systems of medicines were developed across the globe. Among the various folklore system of medicine, Sowa-Rigpa” is one of the oldest well recognised and widely accepted system of folk-lore medicine in the world. It is one of the commonly used of system of medicine in different parts of Tibet, Bhutan, China, former Soviet Union (some parts), Himalayan ranges, Magnolia and, Nepal. The exact origin of Sowa-Rigpa system of medicine is still not known. In the present scenario due to the awareness among the people about the determental effects of the modern chemical drugs, people preferred to use herbal based system of medicine to treat diseases. So, it is needed to understand the floristic wealth of tradional system of medicine to identify the important plants with potential source of drug candidate molecules. In the present chapter an attempt has been made to study the folklore plants used in Tibetan Mountain based Sowa-Rigpa system of medicine and food. Total 332 plant species presented as the most important in Sowa-Rigpa system of medium.

INTRODUCTION

Potato plays a vital rolein foodsecurityworldwide. It is the third most important food crop, afterrice and wheat. It is a nutrient-rich crop which provides more calories,vitamins and nutrients per unit area than any otherstaple crops. FAO declared potato as the crop to address future global food security and poverty alleviation during2008. In Indian agriculture, potatoplays a very important role as it alone contributes about 21 percent of the total vegetable area and 26 percent of total vegetable production of India (DAC&FW, 2017a). As per FAOSTAT data for the year 2017,India with48.6 million t is ranked second in potato productionin the world, onlybehind Chinawith 99.2 million t (Figure 1).

INTRODUCTION

Potato production in India has shown a steady increase in the past, presently making the country second largest potato producer in the world. As per the latest available data, during 2018-19, approximately 52.5 million metric tons of potatoes have been produced (NHB, 2019). Increase in production, often resulting in gluts at harvest, has led to several post-harvest problems like storage and proper utilization of the produce. About 90% of the potato crop in the countryis harvested during January-February in the Indo-Gangetic plains comprising the states of Punjab, Haryana, UP, Bihar, West Bengal, MP and Gujarat where the harvest is followed by rising temperatures of hot and dry summer, and further by warm and humid rainy season. Since potato tubers contain about 80% water, under such circumstances, a semi-perishable commodity like potato, cannot be stored for more than 3-4 months without refrigeration because of very high losses due to shrinkage, sprouting and attack by microorganisms.

Therefore, potatoes are mostly stored in refrigerated cold stores maintained between 2-4^oC and 90-95% relative humidity (RH). Low temperature storage has advantages of natural control of sprout growth, low evaporative losses and minimum risk of diseases and pests. These conditions are ideal for storage of seed potato but these cause cold-induced sweetening leading to excessive accumulation of sugars in most of the potato cultivars making them unfit for processing due to browning in chips. Also, such tubers are less preferred for consumption because of sweet taste. Hence, potatoes meant for processing are either stored under non-refrigerated conditions for short term or stored at 10-12^oC with the use of some sprout suppressant like CIPC (isopropyl N-(3chlorophenyl) carbamate) to minimize the accumulation of reducing sugars. The chips produced from such tubers are light in colour.

Potato processing on the other hand is essential to sustain the increasing potato production in the country and to provide proper remuneration to the cultivators. Potatoes can be processed into a variety of products. Potato chips, French fries and dehydrated chips are the most popular processed potato products in the organized and unorganized sectors. The present chapter deals with postharvest management of potatoes in terms of dormancy and sprouting issues and storage technologies for seed, table and processing potatoes. Besides, areas suitable for growing processing potatoes in the country, potato processing scenario in the organized and unorganized sectors are also discussed.

INTRODUCTION

India is the second largest producer of potato in the world contributing about 12.52%of production from 11.29 % area under potato with an average yield of 22.31 t/ha. Potato is grown in almost allthe states in India under diverse agroclimatic conditions. About 90% of the total potato area is located in the subtropical plains, 6% in the hills and 4% in the plateau region of the peninsular India. Indo-Gangetic plains account for about 76% of the potato area and about 87% of the potato production in the country. Availabilityof assured qualityseed is the most important production constraint in all the potato growing regions of the country.

Seed is the basic vital input in agriculture and its timely availability in adequate quantity as per demand decides the strength growth of agricultural economy in the country. Seed has played a very important role in India’s green revolution and shallcontinue to be the importantcomponent in the days to come. There is a saying “as you sow, so shall you reap”, which traditionally relates to the quality of seed determining the production, has been the wisdom of our forefathers. The traditional farmers’ practices are to save their own seeds generally selected from healthy plants from fields which are freefrom diseases pests, harvest them separately, clean, cure and then store in containers and inspect regularly for any kind of damage; or they get quality seed from other seed producing farmers onbarter basis, indicating thereby the importance of seed in their production system.

INTRODUCTION

Insect pests cause variable and complex problems for potato farmers. Insect pests account for 16% of the crop losses of potato worldwide, and reductions in tuber yield and quality can be between 30% and 70% for various insect pests. India has a greatdiversity of insect pests that attack potato. Thesepests can damage potato plants by feeding on leaves, reducing the photosynthetic area and efficiencybyattacking stems, weakeningplants and inhibitingnutrient transport, and by attacking the potato tubers destined for consumption orfor use as seed. In India, approximately 60 billion rupees (US$1.2 billion)worth of potato tubersare lost annually due to pest damage, which accountsfor 10–20% of total production (Chandel et al., 2013). The potato pests are grouped into soil pests, foliage feeders, sap feeders, and storage pests. Inseed production, aphids and whiteflies are of greatest concern. In ware production, the key pests may be insects which attack tubers, such as tubermoth, whitegrubs, and cutworms. In some situations, foliage feeders suchas noctuid moths and coccinellidbeetles are also important.The Potato cyst nematode (PCN) (Globodera spp.) and root knot nematodes (RKN) (Meloidogyne spp.) are amongst the most economicallyimportant nematode pests of potato. Cyst nematodeshave amazing adaptation for long term survival in the soil, even in the absence of a suitable host whichmakesthemchallenging to the farmers, scientists and policy makers. They are subjected to stringent quarantine and/or regulatory procedures, wherever they occur and presents a serious threat to domestic and international commerce in potatoes. RKNs are prevalent all over the world and can cause significantcrop loss in both warmand cool climatic conditions, depending on their species. In this chapter, the current information on biology, ecology and management of the major potato pests is discussed in the Indiancontext.

INTRODUCTION

Potato (Solanum tuberosum L.) is afflicted by many kinds of viruses and their various strains belonging to different taxonomic groups (Table 1) throughout the world resultingin declinein yieldand tuber quality. Exact estimation of yield and economic losses caused by potato viruses depends on a number of factors mainly strain of the virus, variety, seasonand growingconditions etc. Generally crop losses ranges between 5 to15 per cent if all plants are secondarily infected with PVX and PVS; 15-30 per cent for 100 per cent secondary infection of PVYnand 40-70 per cent due to PLRV. Besides, in Europe and North America Potato spindle tuber viroid (PSTVd) is wellknown to reduce yieldssignificantly (16-64 per cent) dependingon the viroid strain/potato varietyand warmweather (Singh, 1988). Thesevere strains of Potato virus Y (PVY)and Potato leafroll virus (PLRV) have the potential to reduce yield up to 80 per cent, while mild viruses like Potato virus X (PVX), Potato virus S (PVS)and Potato virus M (PVM) can cause up to 30 per cent yield loss in infected plants. Atospovirus Groundnut bud necrosis virus (GBNV) causing severe stem/leaf necrosis disease in plains/plateaux of central/western India heavily infects the early crop of potato. Similarly, a whitefly transmitted begomovirus Tomato leaf curl New Delhi virus-potato (ToLCNDV) known to cause apical leafcurl disease in India, has become a serious problem in North Indian plains.

The viruses can be mechanically transmitted with plant sap, by contact and with seeds. Infectedtubers, whitefly and aphid vectors are importantfactors for the transmission of the virusesin nature. Potatoviruses are transmitted by aphids in two ways. The viruses are either non-persistent (stylet-borne) or persistent and circulative (they are ingested and persist in the aphid throughout its life cycle). The most common persistent and circulative virus affecting potatoes in India is PLRV. Common non-persistent or stylet-borne viruses are PVY, PVA, PVS and PVM. Control of circulative viruses by insecticides is highly effective, which is not the ease with stylet borneviruses. Sustainable potato production is possible only if the virus incidenceis kept under check especially in sub tropics where the weather is highlyconducive both for vectors and the common viruses. In thischapterthe major viruses and viroidof potato including symptomatology, diagnostics and their management have been discussed.

INTRODUCTION

Potatois theworld’s most importantnon-grain foodcommoditythatranks fourth as main food crop in the world after rice,wheat and maize. The crop is grown inmorethan 100 countries, mainly in Asia (195.67 million tons)and Europe (121.76 million tons)(yieldin 2017 as per FAOSTAT, 2019). Because of its efficiency in producing high dry matter, energyand edibleprotein per unit area per unit time, it holds promise for food security in the scenario of ever growing world population. The full potential of this crop however, can onlybe realized if diseases and pests are kept under control, especially in asubtropical country like India, wherethe weather is highly conducive for a number of pathogens.

A number of soiland tuber borne diseases are known to affectthe potato crop causing heavy yield losses. These diseases not only reduce quality and market value of the producebut also spread to new un-infested fields through infected seed potato tubers. Diseasessuch as black scurf, common scab and powdery scab disfigure potato tubers and reduce their market value whereas dry rot, charcoal rot and softrot spoilthe harvested produce during transitand storage. Potatowart is a serious disease which once established is difficult to eradicate and thus require quarantine measures. Bacterial wilt or brown rot of potato is another serious disease which is likely to threaten potato cultivation with the rise in globaltemperature and requires immediate attention.

Potato is becoming a more and more important foodstuff in the world and therefore, its cultivation is expanding fast especially in developing countries. This intensivecultivation, in fact, has led to the emergence of diseases in certain areas where they were of less importance in the past. For instance common scab, known to be a minor disease about2-3 decades ago, is now emerging as serious problem in many potato growing areasof the country including Indo Gangetic plains. Similarly brown rot/bacterial wilt which was endemic in mid hills and plateau region, has now become a limiting factor for potato cultivation in many areasin Madhya Pradesh, West Bengal, north eastern region and in Kumoan hills of Uttrakhand. Sclerotium wilt on the other hand has shown upward trend in plateau region especially in Karnataka. This is because the dynamics of pathogens keeps on changing over time and space and also with the changing farming practicesof a region. Many such new diseases are likely to emerge in a big way in future also, hence warrants regular and careful monitoring. In the following pages, the majorsoiland tuberbornediseases are discussed with special reference to India.

INTRODUCTION

Potato is an important horticultural food crop which has the potential to meet food demand of the fast growing human population across the world, including India. This is going to be the future food crop for the millions especially in the third world countries. However, this crop is highly prone to wide range of diseases and pests that are considered to be the main bottle neck in potato production across the globe. Amongst the biotic stresses, late blight caused by oomycete Phytophthora infestans (Mont.) de Bary has historically been an important disease of potatoes and tomatoes worldwide. In the mid 1800, late blight caused widespread crop failures throughout Northern Europe including Ireland where it was responsible for the Irish famine. Since then, it has spread far and wide and now occurs wherever potatoes are grown. Losses due to P. infestans have been estimated to € 12 billion per annum of which the losses in developing countries have been estimated around € 10 billion per annum (Haverkort et al., 2009). In India, average annual losses to the tune of 15% have been estimated which amounts to 7.95 million tons of potatoes (Current production is 53 MT). Disease appears every year in epiphytotic form in hilly regions whereas in the plains, although it usually appears every year but its intensity is low (traces to 25%). It is only in few years that it assumes epiphytotic form leading to crop losses to the tune of 40%. Recently, late blight has become a serious problem in kharif grown potatoes and tomatoes in Karnataka state (Sharma et al., 2015). Phytophthora infestans is considered as re-emerging pathogen due to regular emergence of its novel strains with increased virulence and its appearance in new locations with surprising intensity. Management of this devastating pathogen is challenged by its remarkable speed of adaptation to control strategies such as genetically resistant cultivars.

INTRODUCTION

Potato ranks third among the major food crops after wheat and rice in the world. It is most important and versatile food of the world. India is second largest potato producer next to china.Potatois bulky and watery in nature and requires lot of energy for production and processing. It is a shortduration crop of 90-120 days, having highest yield per ay per unit area as compared to other major crops. Being a relatively short duration crop in the plains of India, its mechanization assumes a special importance in order to accomplish various farmoperations inverylimited time foritshigherproduction.Manualproduction of potato is time consuming and tedius job, it requires about 1600-2000 man-hours per hectare. With the rising cost of production and depleting energy reserves, increase in crop productivity with minimum input of energy and cost one of the paramount concerns (Garg and Singh 2002). Sustenance of agriculturalproductivitygoes handin handwith mechanization of differentfarm operations, which aims at achieving timeliness of operations, efficientuseof inputs safety and comfort of farmers, reduction in cost of produce and drudgery of farmers (Verma et. al, 1992).With the emergence of new crop rotations and enhanced cropping intensity, many farmers experience scarcity of time and labour. Mechanization plays an important role in timely completing farm operations involved in potato production. It implies a resource management strategy to increase productivity and economic returns. Efforts have been made at various levels to mechanise both production and processing. Various mechanical tools, implements and machinery have been developed for land development, fertilizer application, planting, weeding, harvesting, preparation for storage and on-farm processing of potato (Singh and Gulati 2014).

INTRODUCTION

Information is power in the present age of rapid technological innovations; since information technology (IT) empowers people. IT emerged as the major driver of growth in all walks of life during last quarter of 20^th century and is currently in a steady growth trajectory. It encompasses almost all human endeavors including agriculture. IT can facilitate agriculture in two broad ways; (i) as a tool for direct contribution to agricultural productivity and (ii) as an indirect tool for empowering farmers to take informed and quality decisions which will have positive impact on the way agriculture and allied activities are conducted. Precision farming extensively uses IT to make direct contribution to agricultural productivity. The indirect benefits of IT in empowering Indian farmer are significant and remains to be exploited. The emerging scenario of a deregulated agriculture under WTO has brought about a greater ‘need’ and urgency to make IT an integral part of decision making by agriculture sector. The changing environment faced by Indian farmers makes information not merely useful, but necessary to remain competitive. The farmer urgently requires timely and reliable sources of information inputs for taking decisions. At present, the farmer depends on trickling down of decision inputs from conventional sources, which are slow and unreliable. Besides, the personnel who work for the welfare of Indian farmers, such as extension workers, do not have access to latest information, which hinders their ability to serve the farming community effectively. IT will constitute the primary resource in agri-clinics, agri-business centers, kisan call centers, agri-nukkads, etc. that have been launched by Government of India and other organizations to ensure inclusive growth. Potato is an input-intensive crop and IT will have a special role in making its cultivation more productive and profitable.

INTRODUCTION

Control of weeds below economic threshold level in potato crop is a substantial component of crop management strategy for achieving optimum productivity. In our country, potatoes are raised eitherin assured irrigation or as rainfedcrop with comparatively heavy doses of fertilizers. Therefore, weedsarebound to become menaceduringactive cropgrowth period of this cropand theseundesired plants needs to be controlled in early stages of crop growth by adopting several techniques. Current scenario of crop production is different from past due to manyreasons. Farm holdings are becoming smaller day-by-day and majority of potato growers are small and marginal farmers. They have limitedcapacity for purchase of inputs and farm machines. They need economical, efficient and easier to adopt weed control technologies.Farm labour is also costly nowin many regions as they are migrating towards cities and industrial townships. This scenariobecomes more complex as weeds would be major challenge due to global warming, which is slowly changingclimatesof potato growingregions in India.Theconcern forenvironmentalissuesemphasizeuponadoptingsystems and integrated approach for managing weeds in such away that thesedo not reducethe potato and system productivity (CPRI, 2014).

INTRODUCTION

Agricultural biodiversity is the basis ofglobal food security. Wide variety of crops, soil and cropping systems are nurtured by human culturaldiversity since times immemorial. Potatois a majorfood crop which is widely acknowledged now. It is consumed by the world’s largest population than any othervegetable, produces more calories and protein per unit of land and time than any other food crop.Potatohas much potentialfor sustainable, non-chemical farming, fits well with many crop rotations,and does very wellwith naturalfertilizers. Over the years chemical based farming has started experiencing reduced production and increased costs, orboth (Singh et al.,2011 and Sreenivasa et al., 2010). Monoculture of crops such as rice, wheat and cotton etc., depletes topsoil of nutrients and reduces diversity of beneficial microbes leading to reduced soil productivity. It is finally making the crop plants vulnerable to parasites and pathogens. Environmental pollution caused bychemical fertilizers and pesticides is posinga serious threat worldwide (Doranet al., 1996). Healthy soil is the foundation upon which sustainable agriculture is built. Farming practices differ mainly based on soil inputs and crop protection measures (Devarinti,2016).Thusthere is growinginterestinorganicallyproducedproducts and farmers are shifting from conventional to organic farming. In India, Sikkim is the firststate where completelyorganic farmingis adopted. Farming practices differ mainly based on soil inputs and crop protection measures (Devarinti, 2016) in different regions. Different types of farming based on use of natural products are described in the chapter.

INTRODUCTION

Potato (Solanum tuberosum L.) is one of the major food crops whichrecorded total globalproduction of 388.1million metrictonnes(mt) in 2017-18. Out of the major staple food crops, potato production (388.1mt) is exceeded only by maize (1077.98 mt), wheat (761.88 mt) and rice (494.88 mt) (FAOSTAT, 2017). According to the three years (2012-2014)averages,globally, India ranks 3^rdin area and 2^ndin terms of production nextto China. Thenutritional quality, high productivity and acquiescence for inclusion in intensive cropping systems of this shortduration crop reflects its great potentialin modern agriculture to feed theexponentiallyrisingpopulationin the developingcountries. But, theintensive cultivation of potato crops urges increased use of fertilizers, pesticides and other chemicals leading to high input costs with plateauingyields. Blanket dose of fertilizers as well as imbalance use of nutrientsnot only increases the cost of farm inputs but also degrades soil condition and causes severe environment pollution. Indiscriminate use of insecticide as well as fungicide is verycommon in potato crop which contaminate the environment and deteriorate product quality. Therefore, the chemical inputs need to be optimised based on actual requirement of the crops for sustainable crop production. Furthermore, potato production is associated witha high tillagepractices, number of tillage operation would depend on soiltype, previous crop etc.

INTRODUCTION

Potato is a highly versatile crop grown in varying environmental conditions viz. plains, hills and plateau in India. It is grown under short days (SD) in the plains in autumn season and under long days (LD) during summers in hills. Therefore, the pattern of growth, duration of crop as well as the yield varies according to the environment. Besides, the potato cultivars differ from each other in relation to their morphological characters, response to the environmental factors and finally in yield and the dry matter accumulation. The biochemical reasons for such variations are not clear, but it seems that genetically determined differences in the synthesis of growth regulators such as auxins, cytokinins, gibberellic acid (GA) and abscissic acid (ABA) play an important role and their proportion at different growth stages affect the growth and development and thus, the yield of the cultivar (Minhas and Singh, 2003).The present chapter deals with the physiologicalfactors, which determine the growth, development and yield of potato crop.

INTRODUCTION

Potato is a vegetatively propagated crop mainly through tubers. Seed is the costliest input, which constitutes nearly half of the production cost. Due to the high cost of seed, seed replacement rate is low, which results in build up of various tuberborne diseases.To maintain high tuber yield, multiplication is done through “Seed Plot Technique” (SPT), which involves seed production in low aphid pressure period to minimize transmission of viruses and also adopt a set of cultural practices aimed at minimizing disease spread. The production of healthy seed tubers through SPT is expensive and the low rate of tuber multiplication (normally 68 times) provides only a limited quantity of quality tubers. Further, the low aphid areas suitable for producing healthy seed in the country lie in the northern plains and high hills (> 1800 m above mean sea level). Changing climate scenario is likely to shrink the window for potato cultivation and increase pathogen/vector attacks across the country thereby seriously limiting quantity and quality of seed in the country. An alternative technology of true potato seed (TPS) or use of botanical seed has shown great potential for producing both diseasefree healthy (quality) and cheaper planting materials for commercial potato production. This chapter describes the classical TPS technology and two novel potential TPSbased technologies in potato propagation.

INTRODUCTION

Potato (Solanum tuberosum L.) is the most importantnon-grain food crop of the world and is central to global food security, offeringhigher yields in calories per acre thanany grain.More than 2 billion people worldwide are estimated to be dependent on potato for food, feed or income. Global potato breeding concentrates on the objectives of increasing the yields through resistance to various biotic and abiotic stresses along with improving quality traits but the cultivated potato is an auto-tetraploid (2n=4x=48), clonally propagated, highly heterozygous, and suffers acute inbreeding depression. All these characters complicate genetics/genomic studies as well as breeding efforts to improve important traits such as disease/pest resistance, processing quality and nutritive value.This has lead to the need of high quality, well annotated genome sequence of potato along with high resolution mapsfor aiding the identification of allelic variants for important agronomic traits in potato. Multiple linkage maps have beenconstructedfor potato usingvarious molecularmarkers like RFLPs, AFLPs and SSRs in an effort to develop markers for marker assisted breeding and facilitate map based cloning. These earlierefforts got unequivocal boost when an internationalcollaborationof13countriesviz.Argentina, Brazil,China, Chile, India, Ireland, The Netherlands,New Zealand, Peru, Poland, Russia, the United Kingdom and the United States came together to form the Potato Genome Sequencing Consortium (PGSC) with aim to decipher the potato genome (Xu et al., 2011). The potato genome sequence has provided a major boost to gaining a better understanding of potato trait biology, underpinning future breeding efforts. This would greatly help in enhancing the breeding techniques by implementing the genome assisted methods for imparting the greatertolerance to various biotic and abiotic stressesand ultimately increasing the yields. The knowledge of the complete genome sequence is an invaluable resource for the identificationof genes and variant/novel alleles of genes for everytrait ofinterest to potato breeders. This is very much required for feeding the ever burgeoning global population.

INTRODUCTION

Potato (Solanum tuberosum L.) is 3^rd most important noncereal food crop in the world, after rice and wheat, and popularly known as ‘the king of vegetables’. Potatoes are considered as a nonfattening, nutritious and wholesome food, which supply important nutrients to the human diet. Tubers contain significant concentrations of vitamin C and essential amino acids. Potatoes can be consumed in many ways, including baking, boiling, roasting, frying, steaming, and microwaving. It is integral part of food and traditional cousins and likely to find more importance in the dietary habit. Potatoes are either consumed directly or they are processed to give products such as chips and French fries, mashed and canned potatoes. Besides being important in human diet, potatoes are also used as animal feed and as raw material for starch and alcohol production. Potato was an occasional dish of the affluent class at the time of independence but now it is the most abundantly consumed horticulture based food by the poorest of the poor in the country. At present about 68% are utilized for table purpose, 7.5% for processing; 8.5% for seed and remaining 16% produce goes waste due to pre and postharvest handling.

INTRODUCTION

India has emerged as second highest producer of potato in the world, after China. The crop has been identified as the most important crop for ensuring food security for the developing countries, and a highly nutritious food providing more calories, vitamins and nutrients per unit area of cropped land than any other staple food. The crop has witnessed phenomenal increase over the seven decades of potato research in India. For a crop which was introduced in the country only in the early 17^th century, and was neither adapted, nor its staple food, the remarkable increase in potato production and productivity is an exceptional achievement of breeding this temperate introduction into the present day potato cultivars.

BREEDING REQUIREMENTS

The table potatoes introduced in India were adapted to long photoperiods of up to 14 hours and crop durations of 140-180 days allowing them to be cultivated only in the hilly regions of India. The unique and diverse agro-climatic condition of the country, comprising of contrasting conditions in the Indian plains, where potato could be grown in the winter months necessitated breeding efforts to develop the potato varieties suitable for the sub-tropical plains and the other potato growing regions. The winters in sub-tropical plains have short photoperiod (with about 10-11 hours sunshine) and the crop duration is limited to 90-100 days because of short and mild winter. Further constraints on photosynthetic activity due to early morning fog, posing a strong limitation on tuber bulking. This is followed immediately by a long hot summer period, which coincides with the post-harvest storage period of potato, creating challenging storage problems. The rapid degeneration of seed stocks, with concomitant decrease in yield due to accumulation of viral diseases and tuber storage and utilization in hot and humid climate thus needed to be addressed, in priority. Besides, these southern, north Bengal and Sikkim hills and the plateau offer agro climatic area specific problems related to the biotic and abiotic stresses prevalent in the regions. Moreover, the unique reproductive biology of the plant made it possible to flower only under the long day conditions of the hills, where hybridization was initiated at Kufri (Shimla), Himachal Pradesh. However, during the initial years, it was not possible to evaluate the breeding progenies in the warmer sub-tropical plains due to the quick degeneration of hill bred progenies and dormancy of hill potatoes.

INTRODUCTION

Potato belongs to a genetically diverse genus Solanum having nearly 235 tuber bearing species. These speciesform a polyploid series ranging from diploids (2n=2x=24)tohexaploids (2n=2x=72), with12 asthebasic chromosome number. There is also arichdiversity within the cultivatedspecies of potato and they were initially grouped under six different species. Later studies, however, recognized those species as land race populations of S. tuberosum, with the eight groups: Ajanhuiri, Andigenum, Chaucha, Chilotanum, Curtilobum, Juzepczukii,Phurejaand Stenotomum(Spooner & Salas, 2006). Thisrich genetic diversity of the species is available in the Andean mountain where potato originated. In India,however, it was quite natural that genetic variability within the locally available material will be meager since, it was introduced here only about 400 years ago. On the contrary, more than 500 differentvarieties existed in India by 1940. This paradoxical situation was primarily due to assigning different local names toasingle variety in different parts ofthe country. The available local varieties in India consisted of both early introductions belonging to either pure Solanum tuberosum ssp. andigenum or their hybrids with S. tuberosumssp.tuberosumas well as later European introductions belonging to S. tuberosum ssp. tuberosum.

INTRODUCTION

Potatois an important crop for food and nutritional security of India. Itis mainly grown as rabi crop and 90 per cent of itscultivation is confined to northern Indo-Gangetic plains comprisingthestatesof UttarPradesh, WestBengal,Bihar, Punjab and Haryana. Due to climate change, the main potato season is likely to be warmer than the rest of the seasonsof the year and will affect seriously the potato production in India. Climate change is defined by Intergovernmental Panel on Climate Change (IPCC) as a plausible future climate thathas been constructedfor explicitusein investigatingthepotential consequences of climate change. It is the difference in climate over a period of time (with respect toa base line or a reference period) and corresponds to a statistically significant trend of meanclimate or itsvariability persistent over along period of time. Climate change may be due to both natural aswell asanthropogenic factors. Reference periods are typically of three decadesused as climatological baseline period in impacts and adaptation assessments to Global climate model. The future climate minus baseline climate are used for model scenario comparison of most climate variables. Typically a number of fixed time horizons in the future are produced from model output.For example 2020 (2010-2039), 2050 (2040-2069), 2080 (2070-2099). Future climates are estimated through models, called global circulation models, or global climate models (GCM). GCM simulations are carried out by means of a large set of heavy computations. The IPCC TAR reported 7 GCMs for developing climate scenarios while IPCC FAR reported 21 different GCMs.

Introduction

At the time of inception of CPRI, in the year 1949, India used to produce 1.54 million tonnes potatoes from 0.234 million ha area at an average productivity level of 6.58 tonne/ ha. As per the first advance estimate of the NHB, the potato production in India during 2018-19 was 52.5 million tonnes from 2.18 million ha area at 24 tonnes/ ha productivity. The potato production, area and productivity increased over 7 decades by 34, 9.3 and 3.7 times, respectively. ICAR-CPRI has been adequately recognised by the nation on several occasions for this stupendous contribution. However, potato in India still has to transform from simply a vegetable supplement to serious food security option. Ability of potato to produce highest nutrition and dry matter on per unit area and time basis, among major food crops, made FAO to declare it the crop to address future global food security and poverty alleviation during 2008. Rising number of working couples, rapid rate of urbanization, enhanced tendency of eating out of home, higher disposable income levels of people and important place of potato in fast food items, create an ideal situation for expansion of potato consumption in the near and distant future.

A perusal of various R&D efforts and outcomes in the field of agriculture in general and, more specifically the potato, reveals that “Business as Usual” scenario would not hold much longer. We have to anticipate and get ready to tackle much more complex and diverse future challenges in our respective fields. As the time lag between research and development efforts and the final application/ adoption of the output may stretch over decades, a long term vision and blueprint of action plan is highly important. This chapter attempts to envisage long term state of affairs of potato industry in India and formulate a strategy to fulfil national needs through a well-documented plan to tackle anticipated challenges.

Greenhouse technology development has made good progress in India during the last two decades, and steps necessary for promoting greenhouse cultivation of flower and vegetable crops have been started. Energy-efficient greenhouse cultivation continues to be an area of active research and development, and this is sought to be achieved through precision equipment and protocols. While the gap between the demand and supply of most horticultural crops remains wide and the country plans to double the production of horticultural crops by 2012, the protected cultivation technology holds the key to meet the targets. It clearly emerges that greenhouse technology has multipurpose application for sustainable development of a hilly zone. During harsh winter which otherwise threatens the survival of human beings in these remote hilly areas, popularization and further improvements in greenhouse management could provide a sign of relief in solitude of white snow cover.

The popularity of greenhouse-grown produce continues to rise as it provides a variety of produce during the “off” season. Greenhouses are good for healthy plant nursery production and other a number of crops for profit. Though the greenhouse farming in India like in other countries is progressing but there are certain problems and constraints as stated below.

1.Greenhouse production generally is highly technical and requires constant and continuous attention during cropping period. Relevant information about the crop environmental requirement such as right temperature, humidity etc is essential.

2.Knowledge about the right type of inputs for greenhouse production is a must which is not easily available.

3.Greenhouses cultivation increases the land, water and fertilizer productivity along with reduction in pesticide use. But such interventions are associated with very high initial cost. Although, it is linked with several Government Schemes in India and have 50-90% of subsidies depending on intervention, status / socio-economic condition and policy of State and Central Government.

4.Uninterrupted and regular power supply is required for operating cooling and heating system of the controlled environment greenhouses which necessitate a back-up power pack which is also expensive and underutilized.

Nutrient film technique popularly known as NFT is one of the methods of soilless farming or hydroponics where in plants have their roots in a shallow stream of recirculating water containing all the nutrients required for plant growth dissolved without any solid growing medium. The lower portion of roots remain submerged in flowing nutrient medium in a water tight gully having enough air for the roots. The nutrient film technique was developed during the late 1960s by Dr Allan Cooper at the Glasshouse Crop Research Institute, England. The method is already used in commercial horticulture in many countries including India. NFT is potential for other crops such as animal fodder and even energy-source plants for fuel production.

NFT related technologies

Hydroponics : Cultivation of plants in nutrient solutions is known as hydroponic cutlivation. This ia gerally done under protected structures and in containers arranged horizontally or vrtically (vertical garden). Use of nutrient film or fertilizers is made to feed the plants. Hydroponics can be practiced following nutrient film technique method, trough method, deep water floating method and coco peat bag culture.

Soilless media or culture

Gravel culture is a general term which applies to the growing of plants without soil in an inert medium into which nutrient solutions are usually pumped automatically at regular intervals. Haydite (shale and clay fused at high temperatures), soft- or hard-coal cinders, limestone chips, calcareous gravel, silica gravel, crushed granite and other inert and slowly decomposing materials are included in the term “gravel”. The more important greenhouse flowering crops include roses, carnations, chrysanthemums, gardenias, snapdragons, lilies, asters, pansies, annual chrysanthemums, dahlias, bachelor buttons and others.

Media ingredients and Mix

Commercially available materials like peat, sphagnum moss, vermiculite, perlite and locally available materials like sand, red soil, common manure/ compost and rice husk can be used in different proportions to grow greenhouse crops. These ingredients should be of high quality to prepare a good mix. They should be free from undesirable toxic elements like nickel, chromium, cadmium, lead etc. Most common medium other than soil used in India in greenhouses is coco peat. In other countries these are Rockwool and Peat-vermiculite.

Pasteurization: The heat treatment given to soil to free it of harmful microorganisms or pathogens and pests is called pasteurization. It kills weed seeds also.

Pasteurization of greenhouse plant growing media

Greenhouse growing medium may contain harmful pests such as disease causing organisms, nematodes, insects and weed seeds. It is advisable to decontaminate it by heat treatment or by treating with volatile permissible chemicals.

Flooding

Flooding affects both above and below ground ecosystem processes in greenhouses. Below-ground changes may be less obvious, they are as important as the above-ground changes. Soil microorganisms are sensitive to disturbance, and shifts in soil microbial community structure are expected when anaerobic conditions develop from flooding. The useful aerobic microbes are destroyed by flooding. It takes time to built-up their population in the soil to benefit plants. Due to anaerobic condition created by flooding in greenhouse plant roots in soil are not able to breath, function and hence wilting of plants occurs. Flood irrigation in excess create flood like condition in greenhouses at time. Excess water in soils is a major factor affecting plant survival and functioning. In saturated soils, the supply of atmospheric oxygen into the soil is curtailed and various facultative and obligate anaerobic microorganisms use oxidized compounds as electron acceptors for respiration, thus converting them to reduced forms. The reduction and the associated processes influence plant survival, growth and functioning in wetlands. Flood irrigation should always be just wet the soil not flood inviting stagnation of water.

A chain of reactions is initiated upon soil flooding leading to reduced soil redox potential conditions. These reactions include physical, chemical and biological processes that have significant implications on plants growth. Physical processes include restriction of atmospheric gas diffusion in the soil leading to depletion of soil oxygen and accumulation of carbon dioxide. Shortly after flooding, the limited supply of oxygen in soil pore spaces is depleted rapidly by roots, microorganisms, and soil reductants. This process leads to oxygen depletion and reduction in soil oxidation reduction potential followed by a chain of soil chemical changes. The processes that follow include denitrification, reduction of iron, manganese and sulphate, and changing soil pH

Drainage is the natural or artificial removal of excess water from a surface or sub-surface from an area or field or soil or greenhouse. The internal drainage of most agricultural soils in greenhouse is good enough to prevent severe waterlogging. Water logging creates anaerobic conditions that harm root growth in absence of oxygen. Soils need artificial drainage to improve production or to manage water supplies in certain conditions. Though the roots need moisture but they need oxygen too and poor drainage is g result in roots rotting and death of plants.

The irrigation water inside the greenhouse may accumulate and cause anaerobic condition. Similarly plants in pots should not accumulate water. Water should not stand in pots and beds for longer period. If it stays longer drainage is poor and needs to be corrected. It is better to have good drainage system in greenhouses or protected structures.

Besides irrigation rains water seeps in the greenhouse. The drainage system prevents running or its accumulation in low lying portion of the greenhouse. Drainage system in greenhouses is a must for avoiding damage to the crops.

The following various types of irrigation methods and their systems are used in crop production in greenhouses and plant nurseries.

1.Hand Watering

2.Perimeter Watering System

3.Tube Watering System

4.Drip Irrigation System

5.Overhead Spray System

6.Ebb and Flow System.

About 80% of the world population live in developing countries and are dependent on agriculture. Agricultural products, just after harvesting, are dried to the safe moisture level. Open solar drying for drying agricultural products is being practiced since ages throughout the world. Due to its several drawbacks as danger of (dust, rain, ultra-violet rays, birds, animals etc.), advance technique, i.e. greenhouse drying, is being adopted for drying crops to reduce the drying time and increase the quality of the food products.

Drying involves a heat and mass transfer phenomenon in which heat energy supplied to the product surface is utilized in two ways: (i) to increase the product surface temperature in the form of sensible heat and (ii) to vaporize the moisture present in product through the provision of the latent heat of vaporization. The removal of moisture from the interior of the product takes place due to induced vapour pressure difference between the product and surrounding medium. The moisture from the interior diffuses to the product surface to replenish the evaporated surrounding moisture.

The working principle of greenhouse drying is in which the product is placed in trays receiving the solar radiations through the plastic cover and moisture is removed by natural convection or forced convection.

Greenhouse drying are being adopted to reduce the losses and to increase the quality of the dried products. Solar energy is the most promising power source of energy for drying of agricultural products. Most of the farmers adopt open sun drying because it is abundant and inexpensive. But the open sun dried products are also subjected to remarkable losses due to environment. Losses of fruits and vegetables are estimated to be 30%-40% during drying under open sunlight. The post-harvest losses can be reduced by adopting advanced means of drying, i.e. greenhouse drying. The greenhouse dryer can be operated in natural and forced mode as required. Studies reveal that the greenhouse dried products are of superior quality and better colour retention as compared to open sun drying.

There are several systems for greenhouse heating based on heat source and purpose or crops to be produced in greenhouse.

Electric heaters

Unit space heaters, either floor mounted or supported, are normally dependent on electricity supply supported by stand-by generators. Abroad they are fuelled with natural or bottled gas or fuel oil and use fans for heat distribution. This system requires a relatively moderate capital investment, is easy to install, and provides for easy expansion of facilities. If unit air heaters are used, they should be spaced and directed to blanket the entire area with heated air.

Hot Water Systems

Hot water systems utilize metal pipes that can be perimeter, under benches, or overhead fan forced unit heaters can be used. This system requires a boiler, valves, and other necessary controls. Hot water system is simpler to install and normally requires less maintenance than a steam system. Hot water systems are mainly used in smaller greenhouse.

The modern or climate controlled greenhouse requires massive inputs of energy and cost of claddings to grow crops out of season making them high cost structures. However, growing of certain horticulture crops and their nurseries out of season is happening in a sustainable way, using the heat from the sun and soil too. These are called passive solar greenhouses designed to retain as much warmth as possible. This concept has revolutionized vegetable production in Ladakh, high altitudes and other parts of the country in winter months.

The solar greenhouse is especially successful in China and are contributing mainly in vegetable production. Solar passive greenhouses are designed in different shape size using different local and other materials keeping in view the local climate and terrain. The poly houses mentioned earlier such as, low cost polyhoses, Ladakhi poly house, solar trench, polyench are passive solar green houses. Being the opposite of the climate controlled greenhouse, the passive solar greenhouse is heated all-year round with solar energy alone, even when the outdoor temperature drops below freezing point. The indoor temperature of the structure can be higher than the outdoor temperature. The temperature can be around 25°C (45°F).

Such greenhouses have been experimented by Defence Research and Development Organization through its establishment FRL (Field Research Laboratory) now DIHAR (Defence Institute of High Altitude Research), Leh/ Ladakh since 1962 during November to the end of March, the period during which the outside temperature drops there below freezing. The average temperature in the coldest month is between -15°C and -18°C. Over the several decades of research different and effective designs of such greenhouses have been standardized which are suitable to produce fresh vegetables like most of the leafy vegetables, tomato, cole crops and potato at sub zero temperature.

There are different types of greenhouses, the low cost and high cost or low technology or high technology greenhouses. The cost of greenhouse and expenditure on crop production under these greenhouses would vary according to technology to be used and the crop is to be produced. The cost would vary from place to place with location of greenhouse. For each type of greenhouse its cost would vary according to geo-climate, the production practices and input expenditure/availability. The cost of construction of greenhouse in 2019 hence varies from Rupees 500 to 6000 per square meter.

The variety of greenhouses and greenhouse material, equipment and accessories are so many. However, there are certain basic materials that essential in almost all types of green houses. These are

Structural framing materials

Such materialsinclude low maintenance non-heat conducting timber; strong and durable galvanized steel; or light, low-maintenance and sturdy aluminium alloys. Though plastic pipe frames are usable, they are not very strong to withstand snow load or strong wind sheering forces. What one should choose as the framing material would be determined by the material one wishes to use as glazing, his budget and the permanence of the structure one desires. Aluminium is a popular material for greenhouse framework because it is relatively lightweight, rustproof, affordable and easy to assemble. The downside is that it is not a good insulating material and in very cold weather, heat loss from the metal frame could inflate your heating bill. Also, you would need to look for sturdy frames if your greenhouse is located in an area that experiences high winds. Condensation could also occur on an aluminium frame. Wooden structural frameworks for garden greenhouses are also a popular choice for its aesthetic value, natural feel and the ’warmth’ it exudes. It is an easy material to work with especially if you are not using a greenhouse kit for building. Some greenhouse owners would settle for nothing else as they believe it is the only material that complements the natural beauty of plants inside the greenhouse! Wood is a good insulating material so it will not allow heat loss in cold weather. Reinforced wood has superior strength and has an excellent load bearing capacity. Being a natural material, it has the potential to develop mildew or disease and offer a haven to tiny pests. So, when you choose wood to build the framework of your greenhouse, be sure that you pick a high quality hardy wood such as redwood, cypress or cedar. Also, treat wood with non-hazardous chemicals so that your plants are not adversely affected. The preservatives used for wooden greenhouse frames should be pressure treated, salt type or copper naphthenate. Copper naphthenate is a general use preservative used for pressure treating utility poles and timber. It is known to be very effective in preventing mould, mildew and dry rot. It works very well against wood-damaging fungi and insect pests. Pentachlorophenol is a restricted use wood preservative and is toxic to plants and humans. It is not available to the general public and poles or timber treated with it are not suitable for use in a greenhouse. PVC pipe can also be used as support for small greenhouses that are to be covered with polyethylene, but PVC requires additional support to withstand strong winds. Being flexible, PVC can be used particularly well in hoop houses. Though it has the advantage of offering insulation and, if UV treated, are long-lasting, they are not good at bearing the load of hanging baskets and shelving to any appreciable degree. PVC that is treated to be resistant to ultraviolet radiation is also known as UPVC.