eChapters

1. Introduction

A lawn is an indispensable feature of a landscape with a sizeable proportion of space relative to other garden features. It is regarded as the heart of a garden that enhances the beauty of a landscape providing both functional and aesthetic utility. A well maintained lawn at a residential, public or institutional places can be used both for active and passive recreation. It enhance the beauty of surroundings and contribute to real estate value. The turf industry is being viewed as an integrated sector of ornamental horticulture in the developed countries like USA, Australia, China, Netherland, UK, Japan and Denmark. Globally, the turf grass industry has employed skilled workforce for maintaining more than 700,000 athletic fields and over 17,000 golf courses, with an annual worth of $ 20 million each year (Aldous and Chivers, 2002).

1. Introduction

A combination of art and science had been used for a longer but due to the exponential increase in human population and reduction in operational land holdings its practices became narrow. Nowadays, gardening has gained much popularity among people, as the Covid-19 pandemic has forced them to lock themselves in their houses. These days Mass population is involved in gardening for growing their own food, resulting in a more personal approach to more economical, better-tasting, and healthier products (Pawelek et al., 2009). Gardens have grown increasingly significant for producing nutrient-dense food, protecting biodiversity, and conducting biological and ecological research and education. Biological communities, which are interacting groups of numerous species in the same place, can also be found in gardens. Pollinators and other visitors to flowers eat nectar and pollen from flowers, and some may use floral volatile oils, lipids, or resins for their food, shelter, and mating locations (Simpson and Neff, 1983).

1. Introduction

Fenugreek (Trigonella sp.) is one among the world’s oldest seed spice crops and has gained a supreme importance due to its extensive pharmacological properties (Basu and Prasad, 2011; Maloo et al., 2020). In ancient time’s fenugreek plant was well known and used as a medicinal drug by Egyptians (Rouk and Mangesha 1963). The Ebers Papyrus (one of the oldest preserved pharmaceutical documents) detailed therapeutic advantages and descriptions in Egypt circa 1500 BC (Betty, 2008). It has gained great importance due to its multifaceted uses which are being exploited by farmer’s and industrialist for different purposes.

1. Introduction

India is known as seed spices hub because as far as International level of concern, our country is the largest producer, consumer and exporter of seed spices. Seed spices contribute about 51.79 % of total area and 19.06 % of production of total spices in the country. The area under seed spices is about 1.74 million hectare and production is about 1.45 million tons (Lal, 2018). In our national economy, seed spices are play an important role, the demand is increasing not only due to its large domestic consumption, but also for export. Since long, huge demand of seed spices and importing countries in global market look at India for quality produce of seed spices. The ISO has been listed a total of 109 spices, out of which 63 spices are being grown in India and 20 spices are being classified as seed spices. 

. Introduction

A primary issue for modern horticulture is facing two contradictory objectives, such as the need to produce food for the increasing world population and to minimize damage to the environment, which can in turn negatively impact horticulture. Fertilizer and chemical use and manufacture are hazardous to the environment and humans. As a result, new and effective environmentally friendly compounds are required. Plant biostimulants, which are harmless for humans and the environment, are one answer. They are particularly useful for lowering pesticides in agriculture. Plant biostimulants have become popular in farming and cultivation in recent years.

1. Introduction

Agriculture in India is livelihood for a majority of the population and can never be underestimated. Increasing population, increasing average income and globalisation effects in India will increase demand for quantity, quality and nutritious food, and variety of food. Therefore, pressure on decreasing available cultivable land to produce more quantity, variety and quality of food will keep on increasing. India’s food security depends on producing cereal crops, as well as increasing its production of fruits, vegetables and milk to meet the demands of a growing population with rising incomes. To reach world-wide food security, improved food production and food productivity, we need to approve innovative and futuristic advances and technologies to improve crop cultivation, yield and productivity.

1. Introduction

Post harvest storage is a powerful challenge in agriculture, about one third of the fresh fruits and vegetables are discarded because of the deterioration of quality of produce beyond a reasonable standard. (FAO, 2011; OCD, 2014) Any change or damage in the quality of product from harvest till consumption is considered as loss. Post harvest handling practices do not increase the quality of product, rather just slows down the process of deterioration. The quality and shelf life of produce is determined prior to the time of harvest. Various factors such as climate, soil preparation and cultivation, fertigation, pest and disease incidence, crop loads etc influence the quality and flavour aspects of fresh food.

1. Introduction

Agriculture is prime source of living for rural people world wide effective in raising incomes among the poorest compared to other sectors. In Indian economy horticulture has been recognized as one of the most potential agriculture endeavours in terms of exponential growth. The Horticultural crops viz., fruits counting nuts, vegetables with potato, ornamental plants plus cut flowers, spices, plantation crops and medicinal and fragrant plants has developed a prime promoter for monetary growth in numerous of the states in the nation and it pays 30.4% to GDP of agriculture (ICAR website).

1. Introduction

Coriander is a vital spice crop with a grave role in delicious food test. It is a tropical crop and cultivated as a major in Rabi season in chill free extents through the blossoming phase. Especially, all portions of the plant are comestible, but the fresh shrubberies and the desiccated seeds are the parts conventionally used in culinary. Approximately of the diverse forms of coriander are greenery, blossom and capsules. Coriander leaves are mainly ironic in vitamin A, vitamin C and vitamin K, with moderate pleased of nutritional minerals. Though seeds usually have inferior happy of vitamins, they do widely provide significant quantities of nutritional fibre, calcium, selenium, iron, magnesium and manganese. Mostly, coriander plant productivity is around one and three-fourth tonnes per acre of seed. The root is crushed and used as a condiment in useable form.

1. Introduction

Chilli (Capsicum annuum L.) is a major vegetable and spice crop due to its high consumption, nutritional and cash value to farmers and consumers. It is cultivated almost in whole world as consume in the form of green and red ripe fruits. China is the world leader in chilli production followed by India, Mexico, Morocco, Pakistan, Thailand, and Turkey. India is the second largest exporter in the world of dry chilli and its powder. Fruits of chilli are used as fresh salad, cooked vegetable, pickles, souces hot spices in powder form (Parey et al., 2013) and having many medicinal values (Nadkarni, 1927). Fresh green fruits of peppers and red peppers are the major source of vitamin A, C and antioxidant compounds, besides these also found minerals such as calcium, phosphorus, potassium, magnesium, iron, manganese, sodium, zinc and copper. 

1. Introduction

Eggplant or brinjal (Solanum melongena L. family. Solanaceae) is the major vegetable crop of wet and hot climatic zone of south Asia (Srinivasan and Huang, 2008). After China, India is the second largest brinjal producer country in the world (Majumdar and Das, 2020). It is nutritious vegetable and consumed in throughout the world. Brinjal is considered as Indian native crop and it has been cultivated for last 4000 year. India is known to be the Origin Centre of brinjal cultivation, from where it distributed to throughout the world (Choudhury and Malda, 1968). In India, brijnal crop grow almost throughout the year. Brinjal fruit contains moisture 92.7g, carbohydrates 4.0g, proteins 1.4g, minerals 0.3g, vitamins 124 I.U. and vitamin 12.0mg per 100 g of edible part (Kalra et al., 1988). It is used as vegetable purpose as well as pickle (Singh et al., 1963).

1. Introduction

India’s horticulture production has exposed multiple rises in the historical two decades and the country is ranking second in the world next to China. The horticultural crops viz., fruits, vegetables, flowers, spices, plantation crops and medicinal and aromatic plants have become a vital motorist for economy development in numerous states in India. Horticulture contributes 30.4 per cent to GDP of agriculture, which calls for the need of research and technical backstopping in this sector. Horticulture is a division which has the potential to create multiple springs of income, thereby boosting the economic growth of a country. Horticulture can be undertaken as market driven cultivation of vegetables, fruits and flowers, as ecotourism, as therapeutic medicinal plant harvesting and as a part of multiple farming to accompaniment the main source of income.

1. Introduction

As purveyors of ornamentation, inciters of attraction, symbols of inspiration and peace as well as repositories of beauty, flowers hold special roles worldwide. Flowers have always been associated with mankind since time immemorial because they were used in religious offerings and other social ceremonies. Today; floriculture has emerged as one of the most lucrative business profession and as a major diversification options in the agri-businessin many countries of the world due to higher income per unit area. Floriculture is also known as sunrise sector of agriculture because of its fast growing and increasing demand. In India, about 3,09,000 hectares across the country was used for floriculture and produced 23,88,000 metric tonnes (MT) of loose flowers. India is second largest flower producer after China.

1. Introduction

Underutilized vegetables are essential to the lives of the poor in rural and urban areas, as they provide poverty reduction and environmental sustainability for healthy societies. Traditionally, underutilized vegetables have been known to play an important role in the nutrition of rural communities, especially during droughts, famines and the dry season. Some of these undeveloped resources have been domesticated, but most are still wild and worthless. The potential of these underutilized vegetables has been overlooked as modern agriculture has progressed. These vegetables are also called by different names including minor crops, orphan crops, neglected species, Underused Vegetables, under developed vegetables, local traditional, alternative vegetables and also promising species. Underutilized species have a lot of genetic variety, and they’re tied to a lot of indigenous knowledge. 

1. Introduction

Spices play an important role in human life since time immemorial. Mainly in India, it is not only important as dietary or health product but few spices also have its religious significance. India is being not only largest producer and consumer but exporter of spices also and hence having potential to enhance the economic value of spices. According to Union Minister for Agriculture and Farmer’s Welfare, Spices production in the country grew from 67.64 lakh tonnes in 2014-15 to 106.79 lakh tonnes around 2020-21 having annual increase of 7.90%, along with increase in area from 32.24 lakh hectares to 45.28 lakh hectares. With this increase in production and increasing demand of spices because of their health benefits, spices do have economic benefits and farmers can earn better through it.

1. Introduction

Jackfruit is a fruit crop that is under appreciated and neglected. The jackfruit (Artocarpus heterophyllus Lam.) is a member of the Moraceae family. India is the world’s greatest cultivator and producer of jackfruit, also known as the poor man’s fruit because it grows more in rural than metropolitan areas. It is a pretty huge tree that bears the world’s largest edible fruit. The jackfruit is a tropical fruit native to Southeast Asia. It is thought to have originated in India’s rainforests, in the Western Ghats, and is now widely farmed throughout the region’s lowlands. The leading jackfruit producers in the world include Bangladesh, India, Myanmar, Nepal, Thailand, Vietnam, China, the Philippines, Indonesia, Malaysia, and Sri Lanka. Jackfruit can be found in East Africa, Brazil, and Caribbean nations such as Jamaica. Bangladesh’s national fruits are the jackfruit, mango, and banana.

1. Introduction

Plants offer a rich source of active compounds that have been exploited as scents, flavourings, pigments, pesticides, and medicinal compounds for thousands of years. Plants are thought to utilise these metabolites as a primary strategy for adapting to and surviving in a variety of ecological niches and environmental conditions, as well as to combat biotic intrusions in their environment (Weng, 2014). The increased interest in phytomedicine and medicinal supplements, as well as the increased regulatory obligations for their safety and reputable contents of active compounds, has prompted the development of methodologies for the quality control of multi - component concretes found in plant-derived nutraceuticals. Metabolite diversity in plants is thought to have evolved over time to help plants survive in harsh environments, and it is continually changing. 

1. Introduction

Therapeutic plants have different metabolites in them because of which they are generally utilized in the whole world by individuals to fix different illnesses. India has a rich history of involving many plants for therapeutic purposes. Therapeutic plants are assuming an exceptionally dynamic part in conventional medications for the treatment of different afflictions. India is a rich wellspring of restorative plants because of the varieties in soil, their heights, and other ecological and geological conditions. India’s utilization of plants for medical services goes back nearly 5000 years, when Ayurveda systematized around 8000 natural cures by utilizing plants. Root and tuber crops possess a striking situation in the food security of the creating scene because of their high caloric worth and sugar content. Some of them are as of now under development; however different species are developing wild as a dismissed gathering of financial plants. A portion of the tuberous species is significant due to their restorative as well as modern application. 

1. Introduction

The status of mechanization in India is at a very low level for horticultural crops. The farmers usually go behind the use of traditional methods for different farm operations (Fig 1) and practices for cultivation of horticultural crops, their handling, storage, and processing. This results in less yields, high cost of cultivation and high crop losses from harvesting till processing. The use of different available hand tools, machinery and hi-tech technologies in the production and processing of the crops will lead to increased yields and decrease in losses to a great extent (Mandhar, 1999).

1. Introduction

The Indian economy is heavily dependent on agriculture (employing 53 % population). Around 84 % of the holdings are less than 2 ha while approximately 67% of the farms have less than 1 ha of operational farmland (Government of India, 2013; Pandey and Suganthi, 2015). A large fraction of the farming population is mostly reliant on monsoon rains for irrigation. The condition of the farmers is found to be deteriorating year after year with the revelation that 27% of farmers did not consider farming as a profitable enterprise and 40% were ready to migrate to other avenues for employment (NSSO, 2005; Pandey and Suganthi, 2015). 

A few months back when Sharad Deshpande was talking about some processing tomatoes, I said that there is a lot of history behind processing tomatoes. He said then why don’t you speak on the subject and I said why not. So that is how this talk happened. First, I thought I will speak on breeding tomatoes as its history is even more interesting than what has happened later. I had heard a story when I went to USA for the first time in 1982. I was with Dr Charlie Rick, the father of tomato genetics, in his lab in USDA, UC, Davis, California. He talked about how the processing industry happened, who bred the types suitable for processing, how 80 percent of processing tomatoes of the USA came from California, where we are today and what could be done in this area.

Seed is the primary and most critical input in any crop production programme. A quality seed alone contributes around 15-20% towards total production. The efficacy of all other inputs to increase production will be in vain if the quality of the seed is poor. Hence, use of quality seed is crucial as it appreciably increase the productivity of the crop without depending much on other inputs. This adds to the old saying in Manu Smriti good seed in good field yield abundantly .A quality seed can be defined as genetically and physically pure seeds with high germination percentage, free from seed borne pathogens and safe moisture content. This guarantees good germination, vigorous growth, and good establishment of crop in the field.

History of Seed Industry in India

Farmers dependent mostly on traditional indigenous varieties earlier and its seed requirements were met through their own farm saved seeds or through local sources. But the quality of these seed stocks was not assured, and this resulted in drastic reduction in production as well as productivity of the crops. As a result of various crop improvement programmes, improved varieties possessing high yield potential along with additional characters of biotic and abiotic resistance came into the scenario. But the availability of the seeds of these improved varieties among the farmers remained as a problem and it limited the cultivation of these varieties. This led to the development of a well-planned systemized seed production system. Government of India had framed and brought out different legislations for regulating systemized seed production. These laws are framed to make available quality seeds and planting materials to a common farmer and equip him to approach authority for justice. Seed legislations were initiated in the country by establishment of National Seed Corporation (NSC) during 1963 under Ministry of Agriculture and the seed industry was restructured through the nationals seed projects phase I (1977-78), Phase II (1978-79) and Phase III (1990-1991). These initiatives strengthened the seed industry through formulation of seed regulations, establishment of state seed corporations and seed certification agencies thereby assured the supply of quality seeds to farmers

Technically, seed is the sexually produced matured ovule consisting of an intact embryo, endosperm and or cotyledon with protective covering (seed coat). A true seed consist of an embryonic plant, a store of food which consists of cotyledons and endosperm and a protective seed coat. Seed can also be considered as any material that is used for planting or regeneration purpose. Rather than seed, propagating materials like healthy seedlings, tuber, bulbs, rhizome, roots, cuttings, setts, slips, all types of grafts and vegetatively propagating materials used for production purpose is also referred to as seed. Thus, seeds are of two types namely sexual or botanical seed and asexual seed. Both can be used for raising the crops thus forms the agricultural seeds.

Based on the moisture content present, seeds are of two types, orthodox seeds and recalcitrant seeds. Orthodox seeds are the botanical seeds which contain moisture content less than 20%. Such seeds do not germinate even if the moisture content is more than 20% unless artificially forced to germinate. Recalcitrant seeds contain moisture content more than 20% and such seeds will not germinate if moisture content is less than 20%. These seeds cannot be stored for long and for long storage, special structures or conditions are required. Mostly perennial plant species produce this type of seeds.

The horticulture sector of our country is following an increased growth in area and production by 9% and 14 % respectively for the past six years (2015-21). It is reported that the growth rate of horticultural crop production accounts for 2.7% per year. Fruits and vegetables are the major sectors contributing to total horticulture production. As per the report of second advance estimates published by Horticulture statistics division, Ministry of Agriculture and Farmers Welfare during 2020-21, our country recorded the highest horticulture production during 2020-21 with an annual production of 329. 86 million tonnes from an area of 27.23 million hectares and the vegetable sector shared around 196.26 million tonnes production from 10.80 million hectare area. India is the largest producer of okra and ginger and second largest producer of potato, onion, cauliflower, brinjal, cabbage etc. Vegetables also contribute to the export market and onion, mixed vegetables, potatoes, tomato and green chilli are the main vegetables exporting from our country. It is estimated an export of worth Rs. 4969.73 crores from vegetables during the year 2020-21.

Importance of Vegetable Seed Production

Though we are leading in many of the vegetables in area and production, our national average in productivity of the major vegetables is far less compared to the world average. The country s estimated vegetable production by the year 2050 is 375 million tonnes from 15 million hectare with an average productivity of 25 t/ha. Low productivity is mainly because the farmers are still relying on old varieties which are less yielding and susceptible to pest and disease. Unavailability of the quality seeds of newly released varieties is one of the main reasons for this production gap. A substantial increase in yield and quality of vegetable crops can be achieved by adopting suitable agronomic practices, plant protection measures and use of quality seed. Now a days, there is an increased demand for good quality seeds of open pollinated varieties as well as hybrid seeds through which an increased vegetable production can be achieved for meeting the requirement of increasing population. So far, very limited number of vegetable hybrids have been developed and released by public sectors and majority of the existing promising hybrids in vegetables are from private sectors.

It involves all the steps starting from the extraction till sowing that makes the seed a high quality product for distribution among the farmers for a profitable crop. It reduces the spoilage during storage, increase the shelf life of the seeds, guarantees good germination and field stand thereby reduces the risk of losing the crop at early stages.

Seed Extraction

The seed extraction methods vary with the stage at which the matured fruits are harvested for seed extraction. Some of the vegetable crops are harvested at well ripe stage while some others are harvested at mature dry stage. Proper extraction should be selected taking into consideration the easiness of seed extraction from the fleshy pulp, relatively more seed recovery and less damage to the quality of seeds. There are different methods of seed extraction includes manual method, fermentation method, chemical method and mechanical method.

Manual Method

The manual method of seed extraction varies depending on the harvested fruit type. There are two types of seed extraction in vegetable crops viz., dry extraction and wet extraction.

1. Dry extraction Method

Dry extraction method is following in vegetables where mature dry fruits or mature dried pods are harvested for seed extraction. The harvested dried fruits are kept in sun for 2-3 days. The dried fruits are split open and the seeds are extracted by beating with pliable bamboo stick or by beating against a hard surface. Heavy beating should be avoided to reduce mechanical injury to the seed. Excessive mechanical injury may result in lowering of seed viability. The extracted seeds are dried in the sun between 8.00-11.00 am and 2.00-5.00 pm to reduce the moisture content to a safe level. This is followed in crops like chilli, okra, sponge gourd, ridge gourd, french bean, lablab bean, cow pea, cluster bean etc.

Solanaceae is a plant family that comprising of 2300 species and 85 genera of which, nearly one half of the species belongs to the genus Solanum. The genus Solanum includes both tuber bearing and tuber nonbearing forms. Among the tuber nonbearing forms, the major fruit vegetables growing throughout the world are tomato, brinjal and chilli. They prefer warm humid tropical climate for growth and development. Hence, the agroclimatic regions where this type of climate prevails is suitable for seed production of these vegetables. In addition to this, hybrid vigour has been widely commercially exploited in these crops because of easiness in emasculation and pollination and availability of large number of hybrid seeds per fruit.

Tomato (Solanum esculentum L.)

Tomato is the most important warm season vegetable growing throughout the world. The fruit is valued as salad vegetable and for cooking purpose. It is one of the vegetables from which, a wide variety of processed products are made. The crop is grown throughout the year in one part or other part of the country and it has become one of the indispensable fruit vegetables in our diet. It is rich in vitamin A, vitamin C, niacin, and minerals like calcium, phosphorus etc and it is rich in antioxidant, lycopene which is the carotenoid responsible for the red colour of tomato. Tomato is of recent origin, and it is the native of Peru in South America from where it spread to the entire part of the world.

Cucurbits account for the largest group of tropical vegetables, consisting of cucumber, muskmelon, bitter gourd, bottle gourd, ridge gourd, sponge gourd, snake gourd, pointed gourd, bitter gourd, ivy gourd, wax or ash gourd, chow chow or chayote, pumpkin, summer squash, winter squash, watermelon etc. They all belongs to the family Cucurbitaceae. They are herbaceous in nature and are characterized by tendril-bearing vines and adaptation to warm climate of the tropics and subtropics. Among the different genera of cucurbit vegetables, three genera viz., Cucumis (cucumbers, melons), Cucurbita (pumpkins, squash), and Citrullus (watermelons), are economically important in the world while the others hold regional importance. Most of the cucurbits are grown for its immature fruits and are consumed as salads or cooked vegetable. While, muskmelon and watermelon are used fresh as dessert fruits. Pumpkin and squashes are used in confectionaries besides as cooked vegetables. Mature ash gourd fruits are used in sweet candy preparation.

Cucurbits are low in calories, minerals, or vitamins. However, bitter gourd is rich source of vitamin C, the squash, pointed gourd, and muskmelon contain good amounts of carotene, kakrol is high in protein, and pointed gourd is rich in calcium. Bitterness in some species of cucurbits was attributed by the varying degree of bitter principles, cucurbitacin. Bitter gourd is known for its hypoglycemic activity due to phytoceutical, cheratin in the fruit, which lowers blood sugar level.

Okra is a tropical vegetable cultivating for its tender fruits. It is one of the major vegetable crops in India which can be grown in summer as well as rainy season. Fruits are rich in vitamin A, vitamin C and minerals like calcium, phosphorus, iodine, iron, and potassium. Dry fruit skins and fibers are valued for manufacture of paper and card boards. The processed product, dehydrated okra plays a considerable role in export earnings. Dried seeds of okra found to have 20-24 percent protein and 13-22% edible oil hence, used for edible oil production. Mucilaginous stem is used for clarification of cane juice for preparing jaggery. Roasted ground seed are used as coffee substitute.

Cultivated okra is believed to be originated in tropical and subtropical Africa and phytogeographic studies indicated that it arose in Abyssinian region (Ethiopia). However, existence of large number of related species with wide variability and dominant characters suggested India as the secondary centre of origin. Some researchers suggested Hindustani centre of origin mainly India, Pakistan, & Burma.

Morphology and Pollination

Okra is an erect robust herbaceous annual with green or green with reddish tinged stem. Leaves are alternate, 3-7 lobbed, palmate, hirsute and serrate. Flowers are solitary, bisexual, axillary, peduncle is 2 cm long, epicalyx is up to 10 and bracteoles narrow and hairy. Calyx is fused with corolla hence falls with corolla after anthesis. Petals are 5, separate, yellow coloured with crimson spot on claw. Staminal column consists of numerous stamens (80-120) which are united to the base of the petals. Ovary is superior, stigma is small, 5-8 fid and deep red. Fruit is pyramidal and oblong beaked capsule, longitudinally furrowed, hirsute or glabrous, dehisce longitudinally when ripe. Seeds are dark green to dark brown, round and tuberculate.

Leguminous vegetables include wide range of vegetables which can grow in climatic conditions extending from warm to cool weather. They are rich in protein, essential amino acids and fibre hence, recognized as an important component in ensuring nutritional security. They are growing for its pods for vegetable purpose, seeds as pulse or for dual purpose. They are excellent green manures that fix atmospheric nitrogen into soil and cultivation of leguminous vegetable crops is recommended as an integral component in sustainable soil fertility management. Leguminous vegetables include tropical types namely cowpea, hyacinth bean, winged bean, jack bean, sword bean while, cool season legumes include French bean, garden peas, lima bean and broad bean. They are mostly self-pollinated owing to its cleistogamous flowers. Pole or bush types are available in these crops and all are seed propagated. Among the different leguminous crops, French bean, garden peas and cowpea are under commercial cultivation while other leguminous vegetables are region specific in cultivation.

Cowpea (Vigna unguiculata)

Cowpea is a warm season legume grown both as vegetable crop as well as pulse crop. Tender pods are used as vegetable and dry beans are used as pulse. Cowpea is mainly growing for its seeds as pulse than as vegetable crop. The vegetable types bear stringless pods of more than 30 cm long, fleshy pericarp and higher monosaccharide to polysaccharide ratio. Cowpea is believed to be originated and domesticated in West or Central Africa especially Nigeria where diversity was noticed abundant. The cultivated cowpea, Vigna unguiculata is divided into different cultivar groups viz., pulse type as Vigna unguiculata var. unguiculata, Vigna unguiculata var. cylindrica or var. biflora as dual purpose type for fodder and dry seeds and vegetable type as Vigna unguiculata var. sesquipedalis (yardlong bean/string bean/asparagus bean). The cultivar groups, biflora and sesquipedalis are suggested to be originated from ssp. unguiculata in India and South East Asia respectively.

Cole crops refers to vegetable crops originated from a common ancestor, colewort or wild cliff cabbage (B. oleraceae var oleraceae or Brassica sylvestris L.) and they belong to family Brassicaceae. They prefer low temperature for growth and development hence mainly grown as temperate vegetables in temperate and subtropical climatic zones. This group of vegetable includes cabbage, cauliflower, knol khol, brussels sprout, sprouting broccoli, kale, Chinese cabbage etc. They are Mediterranean vegetables since its centre of origin is considered to be Mediterranean region. Later on, it spread into different parts of the temperate and subtropical countries. In India, cultivation of cole crops was started in the hills where temperate climate prevails and in states like Uttar Pradesh, Orissa, Bihar, Assam, West Bengal, Maharashtra and Karnataka as cool season crop. But with the introduction of tropical types which are more tolerant to high temperature cultivation, cole crops are taking new pace in the cropping system of nontraditional areas. Cabbage and cauliflower became the most widely grown cole crops though cabbage, knol khol and curly kale were the first cultivated types and cauliflower came in the mid-way followed by brussels sprout and sprouting broccoli. The genetic designation of different vegetables under cole crops were described by several workers of which Linnaeus (1753) designated all the cole crops under one species, Brassica oleraceae and in 1969, Neuwhof classified them into different forms as B oleracea var capitata L. (cabbage); B oleracea var botrytis L. (cauliflower); B oleracea var gemmifera DC. (Brussels sprout); B oleracea var italica L. (sprouting broccoli); B oleracea var gongyloides L. (knol khol) and B oleracea var acephala DC. (kale).

Cole crops are usually biennial herbs with tap root system and erect stem. They are highly cross-pollinated and temperature sensitive for the production of head and curd. They are classified as early, mid and late varieties based on the temperature requirement and duration. Among this, early varieties are found to be high temperature tolerant and late varieties are low temperature tolerant. The flowering in cole crops requires a chilling temperature of 4-70C for about 6 8 weeks which transforms the juvenile phase into reproductive stage with exceptions of some early varieties of cauliflower and sprouting broccoli. Upon receiving the chilling temperature, the central stalk will develop into reproductive shoot or multiple reproductive shoots will be formed from the curd. The earlier is seen in cabbage, brussels sprout and kale whereas, the latter in cauliflower and sprouting broccoli. The seed production of cole crops belonging to temperate groups are mostly undertaken in temperate hills especially in the hills of Uttaranchal and Himachal Pradesh whereas, seeds of tropical types are produced in plains and lower hills of India.

Bulb Crops

Bulb crops are cool season vegetables that are grown during the winter months in plains. They are mainly growing for its fleshy leaf bases or fleshy axillary buds or blanched stem and leaves. Major bulb crops that are widely cultivating in our country comprises of onion, garlic and leek. They possess a characteristic odour due to the presence of volatile oil, allyl propyl disulphide (onion) and diallyl disulphide (garlic). They are either seed propagated as in onion and leek or through cloves as in garlic or through bulblets in multiplier onion. Seed propagated bulb crops are annual for bulb production and biennial for seed production. Seed production of bulb crops can be undertaken in plains especially in the central part of the country and southern plains whereas, northern plains hold the problems of Stemphylium and purple blotch during the seed crop and subsequent lower seed yield makes northern plains unfit for seed production. But these areas can be utilized for seed production by following the delayed planting of seed crop and avoiding the climate favouring the diseases.

Onion (Allium cepa)

Onion is a popular vegetable grown for its pungent bulbs. Bulbs are consumed as raw vegetable, as cooked vegetable or in preserved forms. Onion is reported to be originated in Central Asia and Mediterranean region is considered as the secondary centre of origin. It is adapted to a wide range of climate and it is being cultivated in India in three seasons viz., kharif, late kharif and rabi. India is having the largest area under onion cultivation in the world. It is also contributing substantially towards the export of the value-added products from our country. White or yellow onions are commonly using for producing dehydrated products whereas, the red ones are more preferred for direct consumption.

Root crops are cool season vegetables growing for its fleshy root developed from the tap root and hypocotyl region. They are grown during winter in tropical and subtropical condition, throughout the year in hills and spring-summer in high altitude hills. The major root crops growing in our country include carrot (Umbelliferae), radish (Brassicaceae), beet root (Chenopodiaceae) and turnip (Brassicaceae). Two distinct types viz., asiatic or tropical types and European types present in these root crops except beet root. In beet root, European or biennial types only exist. The tropical types are annuals that does not require chilling treatment for flowering. Therefore, seed production of these types is taken up in plains but European types are biennials and they require vernalization treatment after vegetative phase for flowering. Hence, the seed production of biennial types is possible in hills. The seed productions of Asiatic varieties of root crops are done in Punjab, Haryana, U.P. and parts of Rajasthan and Gujarat. Whereas, the seed production of temperate varieties is done in Saproon valley, Kullu valley, Kalpa valley of H.P., Kashmir valley of J&K and selected location of Northeast region specially Sikkim and Arunachal Pradesh. The seed production of beet root is being done in high altitude hills of J&K. All the crops belonging to this group are similar in the cultural practices though they come under different family. All root crops prefer well drained loose and friable soil. Ridge or bed planting is mainly following in all root crops. They are direct sown crops and does not respond to transplanting. They are highly cross pollinated.

The two methods of seed production following in root crops are seed-to-seed method and root-to-seed method. The first method is followed for the production of truthfully labelled seed or certified seed as the seed yield will be more, but quality remains inferior to the second method. The breeder seed as well as foundation seeds require utmost quality hence root-to-seed is preferred for its production. In this method, the matured roots are harvested and the roots are inspected for its trueness. Only true-to-type roots are selected for replanting in the field for seed production and undesirable ones are discarded. The selection and rouging in seed crop are done on the basis of foliage characters and external and internal root characters (colour, shape, size, flesh colour, core size, pungency, indistinct rings etc.). The roots after selection are prepared for replanting by cutting one-third top (shoot) portion and one-fourth to one-half root cut. the prepared stecklings are replanted to obtain good yield of quality seeds. In case of turnip and beet, after selection, the tap root and tops of the roots are trimmed without injuring the crown portion and is replanted.

Potato, the third most important food crop in the world after rice and wheat is becoming the main source of food and income in developing countries. India stands second in production and area of potato in world after China leaving behind the Russian Federation. In India, potato is an important component in cereal and vegetable-based cropping systems for its ability to produce high dry matter/ha in short duration and high yield compared to cereals. It is grown as mixed crop, intercrop, relay or sequential crop along with other vegetables, cereals and cash crops.

Potato is originated in South America in the high Andean hills and towards the end of 16th century it was first introduced into Europe by Spanish conquerors. In the early 17th century, it was brought to India by British missionaries or Portuguese traders. Thus, potato developed as a temperate crop and was later distributed throughout the world. Cultivated potato consists of two sub species, Solanum tuberosm ssp. andigena and S. tuberosum ssp tuberosum. Subspecies andigena is the primitive form which is adapted to shorter day length and high altitudes of mountains (above 2000). The presently cultivating tuberosum subspecies is adapted to long or short day condition of tropical regions and lower altitudes (500-200m above MSL) and is believed to be evolved from andigena types through selection.

Morphology and Floral Biology

Potato is herbaceous in nature with erect to prostrate stem. Stem is variably coloured from green, purple or mottled green or purple. Leaves are pinnate which ends in single terminal leaflet. Stolon arise from the portion of the plant below the ground. The stolon bears rudimentary leaves and tip is hook shaped. The sub apical portion at the tip of stolon enlarges to produce tubers. Hence, potato tubers are the modification of underground stem with shortened axis and poorly developed eyes. The leaf scar with a subtended lateral bud having underdeveloped internodes is referred to as the eye of the tuber. Potato is a long day plant. Moderate humidity and long day condition favours flowering. Hence flowering and fruit set is observed in hilly tracts. Inflorescence is produced terminally and is usually cymose. Flowers are bisexual, actinomorphic, and hypogynous with 5 calyx, 5 corolla and 5 stamens. The colour of corolla varies from white, pink, lilac, blue and purple. Pollen shedding is through the pores at the tip of the anthers. Mature fruit is a berry. Self-incompatibility is observed in diploid species and tetraploids are self-compatible.

Leafy vegetables are rich source of vitamins like A, C and minerals like calcium and iron. Most of the leafy vegetables are quick growing types and shows good response to manures and fertilizers. Their easiness in cultivation and adaptation to diverse agroclimatic conditions makes it suitable for various cropping systems. Some of them are annual in nature while some others are perennial. Leaves as well as tender stems are uses as vegetable in the cooked form. They are reported to have antinutritional factors, oxalates and nitrates compared to other vegetables. The annual leafy vegetables are widely cultivating in our country and among them, amaranth, palak, spinach and fenugreek are the major ones. These crops are short duration in nature, completes their entire life cycle by 80-90 days and produce good yield and brings monetary returns to farmers in short time.

Amaranth (Amaranth sp.)

It is herbaceous fast growing annual leafy vegetable grown for leaves as well as grains. Vegetable amaranth is reported to be equal or superior in taste to that of spinach. Leaves and succulent stem are good source of vitamin A, vitamin C, calcium and iron and are used as vegetable. High oxalate and nitrate content are reported in some species of amaranth.

The major vegetable species of amaranth cultivating in India is A. ticolor. It is suggested to be originated in South or South east Asia particularly in India. Another vegetable type, A. dubius shows diversity in Central America, Indonesia, Asia and Africa. A. lividus is the popular vegetable type in South and Central Europe. Other leafy species are A. viridis, A. tristis and A. spinosus. A. cruentus, A. hypochondriacus and A. caudatus are cultivating for grain purpose. Taxonomists suggested two sections in Amaranthus namely blitopsis which include leafy types and amaranthus which constitutes grain types.

Exotic vegetables are those vegetables that are introduced or not common in India. Its area under cultivation is comparatively less and most of the growing area surrounds the targeted markets especially five star hotels and restaurants. Now a days, there is an increasing trend in cultivation of these high value vegetables because of increased demand and good profit. Farmers could sell these vegetables at a at a higher price when compared to traditional vegetables. They are mostly cultivated in net houses or poly houses. Some of the exotic vegetables popular in India are asparagus, celery, broccoli, lettuce, parsley etc.

Asparagus (Asparagus officinalis)

Asparagus is a dioecious monocot which produces tender succulent above ground stems known as spears from fleshy underground crown. These tender spears are used as vegetable, for cooking purpose and for the preparation of soups. The white crystalline substance, asparagine present in the juice of young shoots have diuretic properties and is used in cardiac dropsy and chronic gut. Asparagus is mainly cultivating in countries like USA, Germany, Spain, France etc. while in India, it is cultivating only in a negligible area. Asparagus is grouped under cool season vegetables. But newly emerging spears are susceptible to frost though a wide range of environmental conditions can be tolerated by mature asparagus. Asparagus is native to temperate Europe and Asia and has been cultivating for 200 years.

Morphology

Asparagus is perennial in nature and produce erect branched stem and grows upto a height of 1 to 3 m. The crop yield continuously for 10-15 years from the initial year of spear production. Asparagus roots are tuberous and the leaves are narrow and needle like. Male and female flowers are produced in different plants.

Spices are those plants, the products of which imparts strong flavour and aroma to the food. This is attributed to the presence of compounds such as volatile oils present in the plant parts. India is renowned for wide variety of spices and is designated as land of spices. Spices are indispensable ingredient in almost all Indian dishes and cuisines foreign invaders invaded India for spices in ancient times. India is figured as the largest producer, consumer and exporter of spices and spice products in the world. Turmeric and Ginger are the major rhizomatous spices of vegetable origin widely cultivating and using in India. They are known for its antimicrobial and antioxidant properties, hence using in medicines for the treatment of various ailments. Apart from these rhizomatous spices, India is also contributing a major share in the production of seed spices. Around twenty spices among sixty-three spices growing in our country are classified as seed spices. Major seed spices of India are coriander, cumin, fennel, fenugreek, dill, ajowain, celery, anise, nigella, caraway etc. These seed spices are extensively cultivated in the arid to semi-arid region of India as Rabi crop.

It is estimated that, spice production in our country increased from 67.64 lakh tonnes in 2014-15 to 106.79 lakh tonnes in 2020-21 with an annual growth rate 7.9%. There is a corresponding increase in the area of cultivation also. An increase in area from 32.24 lakh hectare to 45.28 lakh hectare was observed. Among the major spices, cumin (14.8%), garlic (14.7%), ginger (7.5%), fennel (6.8%), coriander (6.2%), fenugreek (5.8%), red chilli (4.21%) and turmeric (1.3 %), showed significant growth rate in production. The export of spices contributes around 41% of the total export earnings from all horticulture crops in the country and it ranks fourth among agricultural commodities, after marine products, non-basmati rice and basmati rice.

In modern agriculture, use of synthetic chemical fertilizers are essential in agriculture for sustainable yield but, these have resulted in environmental pollution. The use of synthetic fertilizer could result in serious human health issues and also affects the soil microflora, besides being costly due to high production cost. Further, excess use affects soil processes and result in nutrient imbalances in plants with increased susceptibility to pests and diseases and also affects the symbiotic associations. Under these circumstances, biofertilizers could be an alternative for integrated nutrient management system in horticulture. The entire crop production system depends on soil beneficial microflora and their activities, which makes them highly potential alternatives to synthetic chemical fertilizers.

Biofertilizers or microbial fertilizers are essential for eco-friendly and sustainable cultural practices. The term “biofertiliser” has been defined in several ways due to its unique relationships between the plant and rhizosphere microflora. Biofertilizers mainly include nitrogen fixing bacteria, phosphate solublizing and potash solubiling bacteria.

2.1 Nitrogenous biofertilizers

These biofertilizers augment nitrogen to the plants through fixation of atmospheric nitrogen, either symbiotically or asymbiotically. The major nitrogenous biofertilizers are:

2.1.1 Rhizobium

The word Rhizobium is a Greek word where “rhiza” refers to root, and “bios” refers to life. Rhizobium was first named by Frank (1889) which means ‘root living’ in Latin (Fig. 3). Some species of Rhizobium were later moved to new genera based on phylogenetic analysis. It consists of 49 rhizobial species and 11 non-rhizobial species.

Biofertilizers improve the plant growth due to changes in the microbial community of rhizosphere by production of several substances. Normally, biofertilizers promote plant growth either by facilitating nutrient absorption or by secretion of plant hormones. Biofertilizers also cause inhibitory effects by acting as biocontrol agents on various pathogens so that the growth of plant is enhanced. The mode of action could be either direct or indirect methods

Benefit of biofertilizers have been extensively studied for various agricultural and horticultural crops. However, the effectiveness of inoculated biofertilizers are influenced by several factors. If the use of biofertilizers have to be popularized in horticultural crops, the major factors affecting their performance particularly in relation to soil, plant, quality of the product and application methods have to be addressed. Factors affecting the performance of biofertilizers are:

4.1 Quality of the product

4.1.1 Production process

The high quality of biofertilizers are determined by the production process (Bashan et al., 2014). At the same time, the population density of mother culture and the quality of the final products are directly related (Stephens and Raskm, 2000). As the inoculum consists of a strain, the relationship among the microorganisms interaction in the rhizosphere have to be understood. In the case of more than one microorganisms, the efficiency depends on the various mode of action by various microorganisms which might overlap with antagonistic acitivities (Vassilev et al., 2001, 2006 b). The relationship of microorganisms with plants is not based on the taxonomic diversity, but their functional diversity (Maherali and Klironomos, 2007).

The efficiency of biofertilizers could be assured by enhanced shelf life of the inoculant and biological traits which are a challenge for developing a formulation (Bashan, et al., 2014). Hence, either single or consortia of microorganisms formulation with or without additives determines the efficacy of the biofertilizers. The formulation determines shelf-life during storage and transport, which enhances the persistence of the strain in soil and get maximum benefits to the host plants after inoculation (Manikandan et al., 2010; Schoebitz et al., 2012). Different kinds of carriers are used in the formulation process which affects the overall quality and efficacy of the biofertilizers (Bashan et al., 2014; Herrmann and Lesueur, 2013). Granular inoculants showed good results under stressed soil conditions (Clayton et al., 2004; Lupwayi et al., 2006). Encapsulation of the microbial strain into polymers allow diverse compositions and structures (Vassilev et al., 2005) but, have limitations for commercial production (Bashan, et al., 2014; John et al., 2011). Use of additives might improve the shelf life of the product (Bashan et al., 2014; Malusà et al., 2012; Herrmann and Lesueur, 2013) with introduction of specific substances to enhance the efficacy of biofertilizers.

The inoculum dosage and method of application determines the efficacy of biofertilizers. The quantity of biofertilizers to be applied depends on the type of crop, seed rate and soil edaphic factors. There are 3 methods for inoculation of biofertilizers

Seed treatment: One packet containing inoculant (200 g) is mixed with 200 ml of rice gruel or 40 % gum arabic solution to make a slurry (Fig. 23). Then the seeds required for an acre are mixed in the slurry in such a manner that they have a uniform coating of the inoculant over the seeds. Then, the inoculated seeds are shade dried for 30 minutes. The shade dried seeds should be sown within 24 hours. One packet of the inoculant (200 g) is normally sufficient to treat 10 kg of seeds.

Fruits, vegetables, ornamentals, plantation crops and spices, medicinal and aromatic plants, tubers, are the major horticultural crops contributing to the economic growth in India. Even though the horticultural sector is growing fast, with India being the second largest producer of fruits and vegetables in the world, the productivity and quality have to be improved in order to meet the demand of increasing population. Under these circumstances, ecofriendly techniques needs to be adopted which could ensure food security and sustainable production. Indiscriminate application of agrochemicals and chemical fertilizers in horticultural crops and their residues could harm the human health, soil and environment. Horticultural crops need an ecofriendly technique, as most of the horticultural products are directly consumed. Hence, there should not be any residues of agrochemicals in food products. In the current context, use of ecofriendly, cost effective and organic-based inputs like biofertilizers can maintain health of the soil and good quality in horticultural crops. The application of biofertilizers offers an attractive and sustainable means of improving the quality of food products. Biofertilizers like Azotobacter, Azospirillum and AMF and PGPRs not only supplies the required nutrients to plants, but improves the fruit quality and quantity (Pathak et al., 2017).

Biofertilizers can directly or indirectly influence the growth of plant. The direct influence can be through production of phytohormones or making the nutrients available to plants. The indirect effect can be through management of plant pathogens through biological control. Therefore, the purposeful introduction of biofertilizer inoculants to plant microbiome represents an environmentally sound option that holds a prominent position in order to reduce the dependency on agrochemicals (Adesemoye and Kloepper, 2009; Abhilash et al., 2016; Aloo, et al., 2019).

Microbes in soil can rarely exists as single cells and survive near the plant root canopy or in bulk soils or endophytes or even on plant surfaces (Lorito, 2006). The soil microflora occurs as complex members of microbiota (Hacquard, 2015). Microbial consortia (MC) are unique mixture of organisms which respond to the environment stress and adapt to stresses due to internal beneficial interactions among the microbial community. Ecosystem’s physiological functions by microflora is carried out by more than one microbial species with the functional diversity and succession among different microbial components. The microbial balance among the different microflora of a MC will consist of a continuous shift between actively growing cells and non-dividing cells of the microbial consortia. It has been reported that different microbial populations “talk” to each other by “quorum sensing” mechanism in a given environment by exchanging specific chemical signals (Thompson, 2015). Natural microbial consortia holds many specific properties like stability, functional diversity and perform complex functions. The natural consortia have generated an interest in manpulating synthetic consortia for the benefit of application (Minty, et al., 2013).

Biofertilizer is already proven to be beneficial for agricultural and horticultural crops. The most important pre-requisite for the success of biofertilizer application is the presence of high population of viable cells which will show the desired effect on plants. Biotic interactions along with competition from native microflora is a major challenge to an applied strains of biofertilizers. The formulation is an important parameter for biofertilizer production containing efficient microbial strain with suitable carrier material and additives. The microbial strain needs suitable protective environment to increase their efficiency at the target site and also make it user-friendly. Performance of biofertilizers under field condition is the major requirement for inoculants. Inadequate formulations and poor inoculant quality are the major hurdles for the successful use of biofertilizers.

Formulation of biofertilizers has to be consistant during production, distribution, storage and transport to the farmer/end users. The shelf-life of inoculated microbial fertilizer depends on the formulation with suitable carrier material. If local production and distribution of an efficient native biofertilizer formulations are developed, the present problems in the field performance of biofertilizers could be significantly solved. Specific formulations of native strains for use in saline soils, acid soils, drought, high temperature and eroded soils requires specific formulations. Therefore,use of native strains of biofertilizer formulations which are tolerant to the abiotic stress is an important approach. The formulations of biofertilizers are challenging and limited success has been observed in the commercialization of new biofertilizers. Hence, the search for new formulations has been a continuous approach. However, the choice of the formulation depends on the application method, available equipment, farmer’s convenience, plant inherent characteristics and developmental stage, cost, mode of action and colonization pathway of the inoculated strain. Conventionally, solid based formulations are used, which have problems of low viability during storage and application.

Quality Control is very important in biofertilizer production, which determines the efficiency of microbial strains. Generally, the quality control based on BIS are voluntary in nature. However, some of the biofertilizers are brought under the ambit of Fertilizer Control Order 1985 (FCO) during 2006 (Yadav and Chandra, 2014). At present, biofertilizers are under the FCO with specific quality standards. Biofertilizer production and its sales can be regulated and is a mandatory requirement for registration of manufacturing unit with the State Fertilizer Controller (who is generally the Commissioner or Director of Agriculture Department) under the statutory provision of FCO. Moreover, some officers of the Agriculture Department have been declared as Fertilizer Inspectors at the district level, who are authorized to inspect production and storage facilities and draw samples for quality analysis. National Centre of Organic Farming (NCOF), Ghaziabad under the Govt. of India and its six Regional Centre’s located at Bhubaneswar, Bangalore, Jabalpur, Nagpur, Hissar and Imphal have been declared as testing laboratories. Under the provisions of the FCO act, State Governments can also develop their own quality control laboratories and notify them under the FCO (1985). Peat, lignite, peat soil, humus, wood charcoal or similar material favouring the growth of microbial strain could also be used. The FCO specifications for different biofertilizers are presented below:

It has been well established that the biofertilizers are beneficial to plants and are cost-effective inputs for sustainable production system. However, there are some constraints with respect to its production, which are presented below:

10.1 Production constraints

10.1.1 Raw material

Eventhough there are large number of biofertilizer formulations, only few are considered as good carrier materials for biofertilizers such as peat and lignite. Moreover, its availability in India is limited and the quality is lacking for these carrier materials. Hence, a cost effective and locally available material with increased shelf-life is the need of the hour.

10.1.2 Specificity and availability of strains

As the microbial strains used as biofertilizers are specific to soil and agro-ecological conditions, availability of specific strains for the specific host and soil edaphic factors are inadequate.

Microbes present in the biofertilizer formulations help in microbial processes in the soil which augment the availability of nutrients to be taken up by plants. They are of different types based on their nature and function such as nitrogen fixing, phosphate solubilizing, phosphate mobilizing or biofertilizers for micronutrients. Plants use different strategies for growth promotion at different stages of plant growth and development. Biofertilizers are mass multiplied cultures of specific beneficial microbial strains which improves the fertility of soil and productivity. The nutrients are added through natural processes of nitrogen fixation, solubilization of phosphorus and synthesis of growth promoting substances to stimulate the plant growth. The main sources of biofertilizers are bacteria, fungi and cyanobacteria.

11.1. Bio-enrichment of chemical fertilizers- A new approach

Yield response of different host plant depends on the mineral fertilizer and its fertilizer use efficiency. Generally, such fertilizers are low in efficiency due to environmental and soil factors. A large portion of synthetic fertilizers are lost due to fixation, leaching, run-off, erosion, volatilization, denitrification and precipitation without reaching plants. Hence, there is an economic loss and water and environmental pollution.

Microbial inoculants applied to the soil enhances the uptake of nutrient by plants and increase the efficiency of synthetic or organic fertilizers. In this context, it is possible to impregnate mineral fertilizers with specific microbial strain. A new approach is to incorporate the microbes or microbial compositions into fertilizer compositions.

The soil fertility is depleting in the current scenario of gap between nutrient removal from soil and supplies. Moreover, increase in the fertilizer prices has become unaffordable to small and marginal farmers. There is also a growing concern about the environmental hazards and its threat to sustainable crop production. Indiscriminate use of synthetic fertilizers for intensive crop production has resulted in large quantity of nutrient (particularly P) accumulation in soils which has resulted in generating a dead soil. In this context, the long term use of biofertilizers are considered to be economical, eco-friendly, more efficient, productive and accessible to marginal and small farmers over chemical fertilizers (Subba Rao, 2001). Biofertilizers mainly consists of specific living cells which supplies nutrients to plants through their root system. Microbes in these fertilizers provide nutrients to the plants by nitrogen fixation, phosphate solubilization, phosphate mobilization, and promotion of beneficial rhizobacteria (Bhat et al., 2010). Biofertilizer application improves the supply of nutrients, organic carbon, accumulation of soil enzymes, productivity, soil fertility index, economy of farmers, and maintenance of sustainability in natural soil ecosystem and horticultural crops. The production of efficient and sustainable biofertilizers for crop plants needs to be undertaken to make the biofertilizers popular and efficient. The important and specific research in future may be focused on the following aspects.

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

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