eChapters

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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

7.1 Introduction

Artificial intelligence (AI) is the imitation of human intellect in machines designed to emulate human activities and cognitive functions. These machines are designed to accomplish tasks that normally require human intellect, such as learning, problem solving, perception, and decision-making (Zhang et al., 2022). Horticultural crops, including fruits, vegetables, nuts, and ornamental plants, are of paramount importance in global agriculture, as they contribute significantly to food security, economic prosperity, and environmental sustainability. Nevertheless, the cultivation of these crops poses numerous challenges for growers, such as fluctuating market demand, insufficient resources, unpredictable climate conditions, and the constant threat of pests and diseases (Nowak & Grant, 2018). In recent years, the agricultural sector has experienced a significant shift owing to advancements in Artificial Intelligence (AI) technologies (Liakos et al., 2018). AI has emerged as a powerful tool for the cultivation of horticultural crops, providing solutions for boosting productivity, sustainability, and efficiency (Shrivastava & Kumar, 2021). By utilizing AI, horticulturists can overcome the traditional challenges associated with crop management, resource allocation, and environmental sustainability, paving the way for a more resilient and productive agricultural sector (Garg et al., 2019). The integration of AI into horticultural crop production encompasses a diverse range of applications, including precision agriculture, crop monitoring and management, predictive analytics, automated harvesting, and genetic improvement (Golhani et al., 2018). These applications leverage machine learning algorithms, remote sensing technologies, and data analytics to analyze vast amounts of agricultural data ranging from soil composition and weather patterns to crop health and market trends (Araus& Cairns, 2014). Through intelligent data-driven insights, AI enables farmers to make informed decisions in real-time, optimize resource utilization, minimize waste, and maximize yields (Kamilaris et al., 2017). This technological convergence offers promising prospects for food production, enabling stakeholders to explore new avenues for growth, resilience, and sustainability in horticultural crop cultivation (Mohanty et al., 2016).

6.1 Introduction

Perennial crops are crucial for maintaining food security, despite making up only 4.2–4.7% of all agricultural acreage (Kreitzman et al., 2020). The value of fruit and nut production reached a value of USD 823 billion globally in 2020, with the top five fruit crops being apples (87 Mt), oranges (78 Mt), grapes (77 Mt), mangoes (55 Mt), and apricots (41 Mt) (Statista, 2020). The tree nut business is growing quickly, although making up a smaller share of the world’s agricultural output. Global tree nut output is expected to reach 4.2 Mt in 2019–2020, with almonds, cashews, walnuts, hazelnuts, and pistachios accounting for 31%, 17%, 21%, 12%, and 14% of the nut market share, respectively (Serna, 2020).

Tree crops require a longer investment period before producing a commercial yield; sweet cherry takes three years to attain a commercial yield, while pistachio takes ten (Rezaei et al., 2019). High-density monocultures of cultivars chosen for their potential yield, fruit quality, and disease resistance are part of optimal tree crop production techniques. These monocultures are maintained under intensive, high-input farming systems (Simon et al., 2017). However, inadequate pollination can seriously impair the quantity and quality of these agricultural products, prompting for meticulous dedication to pollination research and management (Bosch et al., 2021; Forbes et al., 2019).

Effective pollination, and on the contrary, situations in which pollination is restricted or deficient, depend on both internal and external factors (Figure 7.1, Table 7.1). The period of stigma receptivity, the lifespan of the ovule, and the quality and availability of compatible, suitable pollen are all considered as intrinsic factors (Howlett et al., 2015). Agronomic methods pertaining to plant nutrition, orchard layout, pest and disease control, pollinator activity, pollen quality, and weather patterns and their effects on flowering synchrony are examples of extrinsic factors(Toledo-Hernandez et al., 2017). Hatfield and Prueger assert that pollination is one of the phenological stages that is most sensitive to temperature, and as such, it has a significant impact on productivity (Hatfield and Prueger, 2015). Climate has been shown to be a key factor in determining pollination success and production in crops including peaches, apples, and almonds.

5.1 Introduction

The application of chemical pesticides is crucial in horticultural production, but it is also one of the most hazardous agricultural operations. Overapplication can lead to significant environmental concerns. Spraying is vital for reducing harvest losses and improving productivity. According to Cho et al.,(2012), 30-35% of production damages can be prevented by reducing harmful insects and diseases through spraying. Plant protection is essential for ensuring yield quantity and quality. Effective pesticide use is crucial, as excessive application can lead to pests developing immunity, destruction of beneficial insects and natural pest enemies, and increased harmful insect populations. Excessive pesticide use also disrupts pollination, preventing fruit formation. The method of pesticide application is key to targeting the correct quantity and quality, reducing environmental contamination, and increasing sustainability (Abbas et al., 2020). Site-specific application rates in precision horticulture can decrease pesticide use. Only 30-40% of pesticides typically reach their targets, with most lost to the environment, contaminating workers and causing pollution. Protecting plants with chemicals aims to prevent infections and ensure healthy growth.

Spray drift can harm non-target plants and contaminate watercourses, posing a severe and costly problem for horticultural farmers using air-assisted variable sprayers (Seol et al., 2022). Spray drift refers to airborne spray droplets moving beyond the intended application area from aerial or ground-based methods. Studies have found that a significant portion of pesticides is lost to the air and ground, with up to 30-50% of the applied pesticides being lost through various means (Abbas et al., 2020). Modern trends emphasize the importance of sensors and precision agriculture for effective pesticide use. Understanding tree canopy physical features is crucial for effective spray application. This study focuses on recognizing and geometrically classifying canopies for adequate pesticide protection. Variable rate spraying targets only the canopy, enhancing pesticide application efficiency (Rathnayake et al., 2022). Electronic methods and innovative equipment reduce operational and environmental costs. Sensors tracking canopy characteristics and spacing ensure optimal use of inputs, promoting sustainability.

4.1 Introduction

Pests and plant diseases pose serious risks to global agriculture (Strange and Scott, 2005; Oerke, 2006). Plant diseases and pests are the natural disasters that can impede a plant’s normal growth throughout the plant’s whole life cycle, from seed formation to seedling growth and may result in plant death (Liu and Wang, 2021). Diseases reduce yields in a number of important crops by 21–30% globally (Savary et al., 2019), whereas insect infestations reduce crop output by 30–33% annually (Kumar et al., 2019). For the management, accurate disease diagnosis and pest identification are essential. Artificial intelligence (AI) techniques can be a crucial addition to enable the monitoring of plant diseases and pests at a coarse scale, as traditional field scouting of these pests and diseases is labor-intensive, subject to bias, and typically shows low efficiency (Mahlein, 2016).

Agriculture is undergoing a revolution because of artificial intelligence (AI), which is replacing outdated techniques with more effective ones (Talaviya et al., 2020). AI intervention in agriculture is helping farmers increase productivity and reduce adverse environmental effects (Sujawat, 2021). The application of AI techniques has created new opportunities for scientific research as well as new instruments and ways for handling and analyzing vast volumes of data. An important benefit of AI is its capacity to spot patterns in data that are not immediately obvious or available to humans. This allows for previously unattainable new insights and discoveries (Angermueller et al., 2016; Eraslan et al., 2019). AI is currently changing how we work and live, yet its influence on pathology and entomology research is still underappreciated. AI’s cost-effectiveness, precision, quickness of performance, and adaptability are its core concepts in agriculture (Eli-Chukwu, 2019). In agriculture, artificial intelligence not only helps farmers use their abilities, but it also guides them to obtain better quality and larger yields with fewer resources (Khandelwal and Chavhan, 2019). AI-based technology addresses the issues that agricultural sector faces and helps to increase efficiency in all areas. These challenges include crop harvesting, irrigation, soil content sensitivity, crop monitoring, weeding, harvesting, and establishing.

3.1 Training

Virtual orchards are sophisticated, simulated environments used to train agricultural robots in a controlled, risk-free setting. These virtual landscapes replicate real-world orchards with high fidelity, incorporating detailed models of trees, fruits, branches, and various terrain features. By leveraging advanced technologies like 3D modelling, physics-based simulation, and machine learning, virtual orchards provide a comprehensive platform for developing and testing robotic algorithms without the logistical challenges and costs associated with field trials. In these simulations, agricultural robots can perform various tasks, such as navigating through rows of trees, detecting and localising fruits, and executing precise pruning actions (Shamshiri et al., 2018). The virtual environment allows for testing different path planning and control algorithms, enabling researchers to fine-tune these systems for optimal performance.

Additionally, virtual orchards can simulate various environmental conditions, such as changing light levels, weather patterns, and the presence of obstacles, providing a robust testing ground for robots to adapt to dynamic scenarios. One significant advantage of virtual orchards is the ability to generate large amounts of training data for machine-learning models. Robots can be exposed to many pruning scenarios, enhancing their ability to generalize and perform effectively in real-world conditions. Furthermore, the use of virtual reality (VR) and augmented reality (AR) can aid in training human operators to control and supervise these robots, improving their proficiency and reducing the learning curve (Sarker, 2021).

2.1 Introduction

Horticulture plays a pivotal role in global food production and is essential for ensuring food security and improving nutrition. However, the increasing pressure on agricultural resources, coupled with environmental challenges, necessitates the adoption of innovative technologies to enhance productivity and sustainability. Artificial Intelligence (AI) has emerged as a powerful tool in this regard, offering unprecedented capabilities in data analysis, pattern recognition, and decision-making. In horticulture, AI holds immense potential for revolutionizing crop and soil monitoring practices, enabling more efficient resource utilization and better management strategies.

2.2 Foundations of Ai in Crop and Soil Monitoring

Artificial Intelligence (AI) forms the backbone of modern crop monitoring techniques, enabling the processing of vast amounts of agricultural data and the extraction of actionable insights. This section provides an in-depth exploration of the fundamental principles of AI, machine learning, and deep learning, elucidating their applications in crop monitoring within horticulture.

2.1.1 Understanding Artificial Intelligence (AI)

Definition and Scope: AI refers to the development of computer systems capable of performing tasks that typically require human intelligence, such as learning, reasoning, and problem-solving.

Types of AI: AI can be categorized into two broad types: narrow AI, which is designed for specific tasks, and general AI, which exhibits human-like intelligence across a wide range of domains. In the context of crop monitoring, narrow AI applications are more prevalent, focusing on tasks such as image recognition, predictive modeling, and decision support.