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Mahua (Bassia latifolia Roxb.), is a deciduous, hard woody multipurpose tree species (Venkatesh,1998). It is very hardy and thrives well on rocky, gravelly red soils and also on saline and sodic soils. It can grow even in pockets of soil between crevices of barren rock. Trees are grown on degraded rocky area including salt-affected soils and forests area.  Mahua prefers tropical and sub-tropical climate. It can withstand drought admirably. A characteristic tree of the dry region is found in north and central India.  It commonly grows in eastern Uttar Pradesh, Madhya Pradesh, Maharashtra, Bihar, Odisha, Andhra Pradesh and Gujarat.  In Rajasthan, it is also found growing on the wastelands particularly in southern part of the state.  The tree is very well known to rural folk since ages in India.

Mahua botanically known as Bassia latifolia Roxb, (Hindi name: Mahua, Family: Sapotaceae) is an economical and multipurpose tree. Its flowers, fruits and oil obtained from seeds are eaten in various ways. Corolla commonly called mahua flowers is a rich source of sugar, containing appreciable amount of vitamins and minerals. Flowers are used for preparation of distilled liquors and potable spirits. Flowers and spent flowers (after fermentation) are also used as feed for livestock. Fruits are eaten as raw or cooked. Fruit pulp can be used as a source of sugar for alcoholic fermentation, whereas dry fruit husk can be used for preparation of absolute alcohol. Seed is a good source of oil. Amount of oil obtained from seeds is higher than many oil seed crops and oil seed-bearing trees. Oil obtained from kernel is used for edible purpose and used for preparation of vegetable oil. In Mahua oil, linoleic and unsaturated fatty acids are found which are useful for cardiac patients because it reduces cholesterol content in blood serum. Mahua oil is used in manufacture of soap, lubricating grease, fatty alcohols and candles. Mahua fat is a rich source of palmitic acid used in cosmetic and pharmaceutical industries. Mahua seeds can also be used for preparation of defatted flour, which has great potential in bakery products. Saponin obtained after extraction has industrial and commercial applications. Cake obtained after extraction of oil is used as manure and has insecticidal properties. The trees provide quality timber wood for various uses. Every part of Mahua yields an economic product of great potential value; hence it is a very useful tree.

1. BASIC NUCLEUS SEED

The seed of the notified variety collected from the evolving institute with all the passport information is considered as basic nucleus seed. This seed is sown in prepared healthy field with more row to row and plant to plant distance than the normal recommendation at required isolation distance. Prescribed dose of fertilizer, irrigation and required plant protection measures are provided.

Off types and diseases plants are rogued out at seedling, before flowering, flowering and at physiological maturity stages. Plants are marked with contrast color thread and observed regularly. Marked plants are harvested separately and its produce is used as source seed for production of nucleus seed for next year. Produce of unmarked plants are used as nucleus seed for production of breeders seed. Harvesting threshing and drying are done without reducing physical and genetic purity. The discolored and diseased seeds are removed. The pure seed obtained is the nucleus seed for seed multiplication chain

Deterioration of Crop varieties in their genetic endowments/qualities has been explained by Kadam (1942). Publication on maintenance and management of breeder seed production (Laverack 1991), and maintennce of self pollinated crop varieies (De Hanns 1953; Parlevliet 2007) explain in detail various aspects in maintenance of the seed quality.

Banded Leaf and Sheath Blight
Diagnostic Symptoms
• From the crop’s seedling stage until crop maturity, this pathogen can infect the plant at any point in its growth.
• The disease initially appears on the first and second leaf sheaths above the ground, and it eventually spreads to the ears, where it results in ear rot.
• The hallmark symptoms of ear rot include the presence of light brown, cottony mycelium on the plant’s ear, small, rounded black sclerotia, early ear drying, and caking of the ear sheath.
• When there is humidity, the infection that first appears on the lower sheath extends to the upper sheaths, causing leaf sheath rot and complete leaf drying.
• When the condition worsens, the majority of the plant’s leaves become blighted, and easily detachable sclerotia form on the lesions.
• The disease manifests as a straw-colored, wet, irregular to roundish patch on both leaf surfaces on the basal sheath.

The biofertilizer technology has paved way for the manufacturers and entrepreuners to establish a biofertilizer production unit due to an increasing demand and awareness among farmers. Biofertilizer production units have already been started with most of them in the southern states of India. The biofertilizers can be produced using different kinds of carrier materials (peat, coal, lignite, clays, inorganic soil), organic materials (composts, soybean meal, wheat bran, sawdust, etc.), or inert materials (e.g., vermiculite, perlite, kaolin, bentonite, silicates). Natural carriers like peat, plant waste materials, composts, sawdust, sludge lignite, clays, coal, vermiculite, perlite and bentonite and mixture of organic and inorganic materials may also be used.

The Government of India is also encouraging a low cost technology by providing a subsidy to establish a biofertilizer production unit . The major equipment’s and other materials required for a biofertilizer production unit with the capacity of 150 metric tonnes/annum are given below

Among subtropical fruit crops mango, guava, bael and aonla are among the most important ones. The productivity of these crops is affected by many factors, among which diseases have their own economic significance. The crops use to suffer from a large number of diseases, however, economically important diseases having significance in agro-advisory are mentioned below.
Mango Wilt and Decline
The mango wilt disease caused by Ceratocystis fimbriata is one of the most devastating diseases (Shukla et al., 2015, 2018b, 2020; Shukla, 2020). Association of Berkeleomyces basicola and Lasidiplodia theobromae in wilt, decline and branch drying has also been observed. Symptoms: Ceratocystis infection on the trees causes dark staining of the affected wood, exudation of gum, leaf drying and ultimately death of the tree (Al Adawi et al., 2003; Shukla et al., 2018b). Later symptoms include vascular discolouration beneath the gummosis (Masood et al., 2008; Shukla et al., 2018b). The symptoms may appear in the form of sudden wilt, decline or branch drying and accordingly the whole tree or branch may die within a period of a fortnight to six months of appearance of first symptom.

There are many manufacturers of biofertilizers in both government and private sectors. Only some of them have been listed here for the information

In India, some of the major horticultural crops productivity is affected by major problems. Some of these have been overcomed by certain control measures strategies. However, a few of them are long lasting and have attained the status of national problems. These are mango malformation, alternate/biennial bearing, spongy tissue in mango, bunchy top of banana, guava wilt, citrus decline, rootwilt of coconut and yellow leaf disease of arecanut.

Mango malformation: Mango malformation was reported for the first time from Darbhanga, Bihar. The disease is more prevalent in northwest than northeast and south India. This disorder is widespread in flowers and vegetative shoots.Three types of symptoms are mainly observed. These are bunchy top phase, floral malformation and vegetative malformation. Bunchy top phase is observed in nursery, bunching of thickened small shoots, bearing small rudimental leaves. Shoots remain short and stunted giving a bunchy top appearance. In vegetative malformation, excessive vegetative branches of limited growth are observed in seedlings. 

Okra

Genetic Resources

Okra [Abelmoschus esculentus (L) Monch.] s a crop of the tropical and subtropical owland regions of Africa, Asia, America and warmer temperate region of the Mediterranean. It is believed to be originated from tropical Asia or may have been existing in Africa and India as polyphylatic species. A. tuberculatus, one of the ancestors of okra occuring in India, has nine wild taxa, of which A. esculentus is popularly grown for pod production. The main region of cultivation and diversity of okra in India, Sri Lanka, Pakistan, Nepal and Bangladesh, are represented by various local cultivars of A. esculentus and A. moschatus (Table1).

Male sterility is a condition in plants whereby the anthers or pollen are nonfunctional. The condition may manifest most commonly as absence of pollen or extreme scarcity of pollen, severe malformation or absence of flowers or stamens, or failure of pollen to dehisce. Just like self-incompatibility, male sterility enforces cross-pollination. Similarly, it can be exploited as a tool to eliminate the need for emasculation and for hybrid seed production on commercial scale in field and vegetable crops. There are three basic kinds of male sterility based on the origin of the abnormality related to functional pollen grain.

7.1. Okra or Bhindi (Abelmoschus esculentus L.)

Okra (Bhindi) is a member of Malvaceae family, earlier known as Hibiscus esculentus, and is an annual vegetable crop grown from seeds in tropical and subtropical parts of the world. Okra, also known as “lady finger” or “gumbo”, is a highly nutritious green edible pod vegetable. Botanically, this perennial flowering plant belongs to the mallow family but is grown as an annual. It is named scientifically as Abelmoschus esculentus. Okra originated in tropical and subtropical Africa and India is suggested to be the secondary centre of origin. There are four species under Abelmoschus genus which includes both cultivated and wild forms. They are A. esculentus, A. manihot, A. caillei and A. moschatus. In India, Okra is widely cultivated in states of Andhra Pradesh, West Bengal, Orissa, Bihar Uttar Pradesh, Karnataka, Assam West Bengal, Orissa, Gujarat and Bihar.

Cultivars/Varieties: Okra varieties differ in growth habit, height of plant, presence of purple pigmentation and ridges on fruit. The popular varieties under cultivation in different parts of the country are Arka Abhay, Arka Anamika, Azad Kranti, Co 1, MDU1, Gujarat Bhindi 1, Harbhajan Bhindi, Hisar Unnat, Parbhani Kranti, Perkins Long Green, Punjab 7, Punjab 8, Punjab Padmini, Pusa A 4, Pusa Makhmali, Pusa Sawani, Red Bhindi, TN Hybrid 8 and Varsha Uphar. Besides, a number of hybride from many private sector agencies/seed companies are marketed. Of these, Varsha, Vijay, Adhunik, Panchali, Hybrid No. 6,7 and 8, Nath Sobha, Supriya, Sungro 35, Aroh 1, - 2, -3, -9 and are more popular.

Uses

Different parts of the plant are used for different purposes. Abelmoschus moschatus Medik. Leaves and seeds are considered as valuable traditional medicine. Abelmoschus moschatus is also called ‘musk okra’ a medicinal plant belonging the same family. The leaves and new shoots of this plant is also used as vegetable. The aromatic seeds of this plant are aphrodisiac, ophthalmic, cardio tonic, antispasmodic and used in the treatment of and intestinal complaints and anxiety.

According to FAO estimates, about 50% total geographical area in India is under various degraded hazards and about 2.1 million ha of land is getting degraded and deforested annually (Sehgal et al. 1998). Out of that underground water in arid and semi-arid areas is saline or sodic in nature. While spices, medicinal and aromatic plants may be a boon for these areas, which not only withstand under adverse conditions but also could be productive and helps in mitigating these problems. However, other crops are remain less or unproductive in these areas.

Spices are low volume and high value crops and have tremendous export potential, which is witnessed by several invasions faced by this Indian peninsula during ancient time. Medicinal and aromatic plants have an equally market potential with the world demand of herbal products growing at the rate of 7 per cent per annum (Aishwath and Tarafdar, 2007). Seed spices and aromatic plants are the natural source of flavour, perfumes and fragrance widely exploited by essential oil industries in the world. Owing to considerable diversity of edaphoclimatic conditions ranging from temperate to tropical and arid to sub- humid that prevails in India and an array of medicinal and aromatic flora occurs in wild state. Many exotic essential oil bearing plants, including mints, citronella, geranium, patchouli, lavender and chamomile have been naturalized in India. As the country has emerged as one of the main producers of seed spices and some of the essential oils, theses plants are significant foreign exchange earners. Some of the aromatic plants especially grasses can sustain both biotic as well as abiotc stresses, even in the areas unsuitable for conventional crops (Aishwath et al., 2008). Most of the seed spices crops are seasonal crops and comes up well with limited moisture and nutrients. Therefore, under utilized natural resources can be utilized profitably by crop diversification.

The National Bureau of Plant Genetic Resources (ICAR-NBPGR) was established in 1976 in New Delhi by the Indian Council of Agricultural Research (ICAR). The mandate of the Bureau was to act as a nodal institute for the acquisition and management of indigenous and exotic plant genetic resources (PGR) for agriculture and to carry out related research and human resources development for sustainable growth of agriculture. As we know our country is a mega-diverse country with 2.4% of the land area, accounting for 7.8% of the recorded species of the world spread over 45,968 (11.18% of world) species of plants and 91,212 species of animals (7.43% of the world) that were documented in its 10 bio-geographic regions. India shares four biodiversity hotspots, namely Western Ghats and Sri Lanka, the Himalayas, Indo-Burma, and Sundaland, and one third of our species of higher plants are endemic. Out of 45,968 plant species, 5150 are endemic and distributed in 141 genera under 47 families, corresponding to about 30% of the world’s recorded flora, which means 30% of the world’s recorded flora is endemic to India. The plant genetic resources are fundamental to human welfare and their effective management is a crucial for conservation of genetic variability. As of today, ICAR-National Bureau of Plant Genetic Resources (ICAR-NBPGR), New Delhi, India has conserved about 4.6 lakh accessions of 1900 species in its gene bank, and about 6900 accessions of intermediate species have been conserved in cryobank. The Bureau not only conserve PGR safely to meet the needs of future generations but also provides these to the nation’s crop improvement programs to sustain continued advances in agricultural productivity and stabilize production. ICAR-NBPGR is the nodal agency for import and export of all PGR for research purpose, adhering to guidelines of National Biodiversity Act, 2002.

Nursery is a place where plants are grown, nurtured and sold out. Generally, various commercial crop growers require a good quality saplings or grafts of genuine type.
 
Diseases and insects are as much a problem in growing plants in the nursery as they are in growing any other crop. It is always better to monitor the nursery continually with respect to disease and insects damage and select the proper control measures or pesticides for identified pests. Horticultural nurseries are heterogenous and especially complex agricultural systems, which present formidable challenges to management of diseases and pests. Moreover, nursery plants transported interstate and internationally can serve as important vectors for pathogens and insects that threaten both agriculture and forestry.

In India, land is limited and shrinking whereas the human and animal populations are increasing. The land and man ratio has fallen rapidly in the past half century from 0.34 in 1950 to 0.14, and is projected to be 0.10 in 2025. Horticultural crops however, have shown substantial growth acceleration (Table 1).The area devoted to fruit production increased 50 per cent, while the vegetable growing area increased 20 per cent. Grape, an export crop, currently at 43,000 ha, increased by 70 per cent. The value of horticultural crops grew at an average of 7.5 percent during the 1990’s. High yield and quality in horticulture can only be ensured through rational blend of commercial fertilizers and organic nutrient sources.

Vegetables being good source of carbohydrates, proteins, minerals, vitamins and dietary fibers constitute important component of human diet. These are the cheapest source of natural protective food and increase the palatability. India is the second largest producer of vegetables next to China. Diseases are inherent component of agro-ecosystem, which must be dealt with continuous and knowledgeable basis. Diseases in the standing crop from the seedling stage until harvest and spoilage caused by microorganisms during transit, storage and marketing are major constraints in increasing production and availability of vegetables. At different stages of vegetable production, disease management requires several approaches, and it is more successful, if it is integrated into crop production system. Since vegetables are mostly grown year after year in the same fields especially near towns and cities, therefore, concerted efforts are required to manage the diseases. More than 300 diseases have been reported to occur on vegetable crops and it is beyond the scope of this chapter to discuss all the diseases. However, brief description of etiology, diagnostic symptoms and management practices being adopted are presented here for the economically important fungal and bacterial diseases of vegetable crops.

Abstract

Indian Himalaya supports wide range of native and introduced temperate horticultural crops and important among them are Malus, Prunus, Pyrus, Juglans, Actinidia, Rubus, Hippophae in fruits; Allium, Amaranthus, Chenopodium, Fagopyrum, Phaseolus in vegetables, Aconitum, Gentiana, Picrorrhiza, Artemisia, Ephedra, Polygonatum, Podophyllum, Taxus, in medicinal and aromatic plants and number of orchids, rhododendrons, Rosa, Begonia, Primula, Delphinium and Tulipa in ornamental plants. Effective utilization of this vast range of horticultural genetic resources thus require their proper deployment which may include (i) use as a breeding material and/ or rootstocks, (ii) directly as variety through introduction or after selection, and (iii) as new crop though domestication. Except few successful examples in crops like Pisum, Phaseolus, Capsicum, Allium, and some ornamental crops, the picture of using genes from wild relatives is not very rosy.

The potential of Vegetable Genetic Resources (VGR) is vast, offering solutions to future challenges such as food and nutritional security. Achieving this requires the identification, collection, conservation, documentation, and utilization of these resources. The introduction and acceptance of improved varieties have resulted in the replacement of numerous landraces and local crop cultivars across various agri-horticultural crops, with a particular impact on vegetables. The alignment of activities related to the management of plant genetic resources at both global and national levels has enhanced the opportunities for utilizing VGR. India possesses a rich diversity of vegetable genetic resources, comprising indigenous and exotic varieties. Information regarding VGR in the Indian region can be accessed through passport data, conservation records, catalogs detailing characterization and evaluation, as well as insights into local vegetable usage, all of which contribute to strengthening these initiatives. This chapter delves into vegetable genetic resources, focusing on economically significant vegetable crops of India, along with regionally important crops, potential species, and their wild relatives, highlighting efforts undertaken at ICAR, NBPGR for its collection conservation, characterization and utilization.

Plant genetic resources are the most valuable and essential basic raw material to meet the current and future need of crop improvement programme. A wider genetic base assume the priority in plant breeding research aimed as developing new varieties for increased crop production. PGR for food and agriculture are a reservoir of genetic adoptability, which act as buffer against environmental changes and economical challenges. The erosion of these resources results in a severe threat to the world long term food securities. The fundamental objective of the genetic resource conservation is the maintenance of genetic diversity within each of the species. In general PGR include all species which contribute to people by providing food, medicine, feed, fiber etc. PGR is our heritage which needs conservation for prosperity.

Genetic resources management is a complex process starting from the identification of a target gene pool for conservation to the use of genetic resources. Many of these activities not only generate but also require geo-referenced data (Spatial data). Analysis of these data can lead to a greater understanding of the eco-geographic representation of existing collections, increasing the efficiency of conserving and managing genetic resources and broadening our understanding of the distribution of genetic diversity. Genetic resource databases could potentially serve as an information resource to a broader scientific community, providing relatively independent global data sets to meet the unique needs of researcher. GIS can merge genetic diversity information with other georeferenced data such as population density, climate, topography and soils, adding value to genetic resources. GIS analysis can help develop conservation strategies, monitor genetic diversity, select potential collecting sites, design in situ reserves and enhance genetic resources use. Currently, GIS use is constrained by limited georeferenced information.