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Horticulture plays an indispensable role in global agriculture, offering a rich diversity of fruits, vegetables, flowers, and medicinal plants that significantly contribute to human nutrition, health, and economic resilience. In the face of rising demand for high-quality produce and environmentally sustainable farming methods, the development and adoption of advanced horticultural production technologies have become more crucial than ever. Spanning a broad spectrum of topics, the book delves into essential areas such as soil and nutrient management, advanced irrigation strategies, precision farming, protected cultivation, and integrated pest and disease management. In addition, it explores cutting-edge trends including organic farming, hydroponics, vertical farming, and the application of biotechnology in horticulture. These technologies not only enhance productivity but also support resource optimization and environmental sustainability. A core purpose of this book is to bridge the gap between conventional horticultural practices and modern scientific advancements. By combining theoretical foundations with practical insights, it offers a holistic perspective on crop improvement. Each chapter is thoughtfully structured to provide in-depth knowledge, complemented by research studies and examples that enhance understanding and application. Special emphasis is placed on crop improvement strategies aimed at enhancing the genetic potential, resilience, and productivity of horticultural crops. Through advanced breeding techniques, molecular tools, and biotechnological interventions, this book highlights methods to develop superior varieties with improved yield, quality, and resistance to biotic and abiotic stresses. These innovations play a pivotal role in meeting the challenges of changing climates, evolving consumer preferences, and the need for sustainable intensification of horticultural production.

Demand-driven vegetable breeding emphasizes the development of new cultivars based on specific consumer preferences, market demands, and environmental conditions. This approach contrasts with traditional breeding methods that primarily focus on agronomic traits like yield or disease resistance. The importance of demand-driven breeding lies in its ability to align agricultural production with consumer needs and market trends. By directly responding to consumer preferences such as taste, appearance, nutritional content, and culinary characteristics, breeders can create vegetables that are not only commercially viable but also meet consumer expectations. This approach enhances market acceptance and profitability for growers, distributors, and retailers alike. Breeders prioritize demand-driven breeding to stay competitive in a rapidly evolving market where consumer preferences can shift quickly. By understanding and responding to these preferences, breeders can develop cultivars that offer distinct advantages over existing varieties, leading to increased market share and improved economic outcomes for stakeholders throughout the supply chain. This chapter provides an understanding on demand-driven vegetable breeding, particularly opportunities, and challenges.

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

DUS testing is a way of determining whether a newly bred variety differs from existing varieties within the same species, or the characteristics used to establish distinctness are expressed uniformly and that these characteristics do not change over subsequent generations. Testing the distinctness, uniformity and stability (DUS) of crop varieties is a statutory requirement before varieties can be entered into the Registers of Cultivars (National Lists) and/or granted Plant Breeders’ Rights (PBR). In India, Protection of Plant Varieties and Farmers’ Right (PPV&FR) Act (2001) provides the registration of new variety of plant if it conforms to the criteria of distinctness, uniformity and stability. Why do we need a DUS test? New (candidate) varieties should be distinct from all other varieties whose existence is a matter of common knowledge, and also sufficiently uniform and stable with respect to the characteristics used to demonstrate distinctness. ‘Common knowledge’ is broadly defined to include all known varieties, i.e. any variety entered into or subject to an application for PBR, varieties grown commercially, held in publicly accessible reference collection, or of which there is a published description (UPOV 2002). The responsibility for DUS testing of potato varieties in India lies with the ICAR-Central Potato Research Institute (CPRI), Shimla, which is the national institute for potato research and development. Currently a set of 51 DUS characters in potato are defined by CPRI and being used for distinguishing new variety.

Genome editing has emerged as a powerful tool for accelerating crop improvement in horticultural crops by enabling precise modifications in their genetic architecture. Considering the development and advantages of genomeediting technologies in improving diverse characteristics of horticultural crops, substantial increase has been reported in recent years including ZFN, TALEN, and especially CRISPR/Cas systems. The CRISPR/Cas technology has proved its potential in altering many genes of interest in horticultural plants including fruits, vegetables, and ornamental plants for improving agronomically important traits and attributes such as growth rate, seed size, flowering time, flower color, storage time, resistance to biotic stresses, tolerance to abiotic stresses, herbicide tolerance, metabolism, fruit color, fruit ripening etc. This technology opens new avenues for more favorable and precise manipulation of plant genomes to improve crop performance. Genome editing has emerged as a powerful biotechnological tool with transformative potential for horticultural crops. It involves the precise modification of plant DNA to enhance desired traits, increase crop yield, and confer resistance to pests, diseases, and environmental stresses. Molecular tools like CRISPR-Cas9, TALENs, and ZFNs act as molecular scissors, allowing for the targeted alteration of specific DNA sequences with unprecedented accuracy. This technology allows scientists to introduce or enhance beneficial traits in crops, including disease resistance, improved nutrition, and drought tolerance. Horticulture is a critical component of global food production and human well-being as it involves cultivation and management of plants for food, aesthetics, and medicinal purposes. Horticultural crops comprising fruits, vegetables, ornamental plants, and medicinal herbs, not only contribute to nutritional needs of populations worldwide but also enhance the visual appeal of our surroundings. However, productivity and quality of horticultural crops face significant constraints due to challenges such as biotic and abiotic stresses, limited genetic variation, and increasing demands for improved traits. Plant breeders have employed various techniques, such as hybridization, selection, and genetic manipulation, to enhance horticultural crops. These approaches have contributed to improved yield, disease resistance, and other desirable traits.

Fruits contribute to nutritional security and thus are an important part of food system. To meet the future demand, development of varieties with improved yield and quality is the focus of researchers involved in fruit breeding. Though conventional breeding has resulted in the development of improved commercial varieties of different fruit crops, however conventional breeding is time consuming and faces several challenges due to long juvenile phase, highly heterozygous nature of most of the fruit crops. Challenges like changing climate, consumer preference, socio-economic conditions like reduced availability of land, labour and increasing cost of inputs, require fast and efficient methods to develop the varieties to meet the demands, which is not feasible with conventional breeding. Marker assisted breeding has given impetus to breeding efforts in several fruit crops, however it’s use is limited only for the traits controlled by a few major QTLs. During last few years, enormous genomic resources have been developed for fruit crops using next generation sequencing technology. Such advances in genomic research in many fruit crops have paved the way for precision breeding using genomic assisted breeding (GAB) tools. GAB has helped in characterisation and utilisation of genome resources and using allele variation for cultivar development (Varshney et al. 2021). Advances in sequencing technology and affordability has allowed the genome wide analysis (GWAS) on diversity panels of different fruits resulting in identification of allelic variation associated with the traits of interest. Also, identification of superior alleles of candidate genes makes them amenable to genome editing based precision breeding. Genome wide genotyping and phenotyping offers tools for developing strategy for genomic selection (GS). Genomic selection relies on the prediction of breeding values of tested genotypes based on the large number of markers spread over entire genome. These tools promise to further improve breeding efficiency in fruit crops.

With the advent of clustered regularly interspaced short palindromic repeat (CRISPR)-associated protein9 (CRISPR/Cas9) genome editing, a fast and efficient new breeding technology, precision breeding in vegetable crops has become possible now. Several genes have been edited and functionally characterized using CRISPR/Cas9 in tomato for multiple traits such as plant type, floral morphology, fruit traits, disease resistance, and abiotic stress tolerance. The CRISPR/Cas9 has been proven in successful introgression of de novo domestication of elite traits from wild relatives to cultivated tomato. The progress in CRISPR/Cas9 based improvement in vegetable improvement, has been discussed. Vegetables are an important source of healthy diet, as they provide essential nutrients including vitamins, minerals, dietary fibre, antioxidants and other phytochemicals. Dietary fiber-rich vegetables improve digestion, while also lowering the risk of obesity, diabetes, high cholesterol and heart disease (Behera et al., 2021). A world vegetable survey showed that around 392 vegetable crops are cultivated worldwide, representing 70 families and 225 genera. Over 97 species of higher plants are being cultivated and consumed as vegetables in India. These crops belong to 20 different families such as Cucurbitaceae (25 crops), Fabaceae (16 crops), Brassicaceae (12 crop) and Solanaceae (6 crops). The world’s total vegetables production was 1,155 million tonnes in 2021 where China ranks first with a total production of 600 million tonnes, accounting for 52.18% of the total world production. The top 5 countries (China, India, the United States of America, Turkey and Vietnam) account for 70.36% of total world’s production. As far as India is concerned,  it is the largest producer of ginger (2.23 million tonnes) and okra (6.47 million tonnes) in the world, while ranking 2nd in potato (54.23 million tonnes), dry onion (26.64 million tonnes), cauliflower and broccoli (9.25 million tonnes), brinjal (12.87 million tonnes) and cabbage (9.56 million tonnes) (FAO 2023).

Probably since the beginning of human life on the planet, they have used local fruits and vegetables. For a long time, they have enjoyed the fruit of the wild trees without knowing how to successfully produce them. Such native fruit trees have many advantages. These trees have an extraordinary genetic diversity that can be exploited in breeding programs and genetic advancement of domestic varieties (Khadivi et al., 2020). Many indigenous fruits are still highly valuable, and the harvesting and selling of these forest fruits contribute significantly to the local economy of families in the area. The product collected from forest trees is completely healthy and in terms of quality, they may even be equal to “organic fruits”. In a most recently published book chapter entitled organic pomegranate production in Iran, compiled by Alizadeh and Varasteh (2024), wild pomegranates were considered as noble source of healthy food. Given the multifunctional, ubiquitous nature of wild edible fruits the present chapter was compiled to introduce wild fruit trees of northern Iran with a focus on providing more detailed information about wild pomegranates. Geographical Aspects of Northern Iran Northern Iran is a geographical region encompassing a relatively large and fertile area, located along the southern border of the Caspian Sea and the Alborz Mountains. Upon closer examination of the map of Iran (Fig. 1), one can identify three northern provinces: Golestan, Mazandaran, and Gilan. These provinces all share borders with the Caspian Sea and the Alborz Mountains. The Alborz mountain range extends from the western border with the Republic of Azerbaijan to the eastern border with Turkmenistan (Fig.1).

Litchi (Litchi chinensis Sonn.), a subtropical perennial fruit tree, belongs to family Sapindaceae and is indigenous to China. Its cultivation spread to the neighbouring countries of the south-east Asian region and other countries. The fruit of litchi is small, heart-shaped, conical or spherical in shape and pinkish red to bright-red in colour, with varying colour intensity in different cultivars. The pulp of fruit is crispy and grape-like in texture, very succulent and aromatic and is generally characterized by a sweet, acid, juicy and soft taste. Because of these reasons, litchi is highly prized in its fresh form as well as in different processed formulations. The total litchi production is about 24,00,000 tonnes from the net cultivated are of about 8,00,000 ha. The main litchi-producing countries are China, India and Thailand, whereas it is commercially grown also in many other countries. Of the total world litchi production, China and India contribute about 90%. Although litchi plants are long-lived, even then new plantings of this fruit are being done regularly, ensuring the continuous growth of production at the global level. In India, where this fruit can be grown in off season also in the southern states of Karnataka, Tamil Nadu and Kerala, the litchi production is about 7,37,200 tonnes from an area of 99,170 ha (Chandrakala et al., 2023).  

The perennial nature of fruit crops coupled with high heterozygosity, protracted juvenility, and lack of information on inheritance patterns of important traits of economic significance is responsible for slow progress in breeding of fruit crops. Citrus is one of the most popular fruit crops cultivated in around 140 countries of the world mainly in the Asia-Pacific region. In Asia, citrus fruits are a major crop for the local people in meeting their nutritional requirements and livelihood. Citrus is cultivated as an indispensable cash crop both for domestic consumption and the export market. Recently, the citrus production has shown an increasing trend mainly attributed to its increased demand as a nutritious and healthy drink owing to the possession of many medicinal and antioxidant properties in its fruits. The clonal selection has been used primarily as one of traditional breeding methods because bud sport mutations arise frequently in Citrus (Iwamasa et al., 1981; Uzun et al., 2004). This method of breeding generally offers many advantages to select clones suitable for their identified uses. Yield and fruit quality are the major targets of breeding and both these can be enhanced through clonal selection of natural mutants or seedlings. The major aim of the clonal selection studies is the selection of clones bearing regularly for many years, improved fruit appearance and tolerance to biotic and abiotic stresses. In general, identifying the elite clones, testing them under different climatic conditions, and freeing them from the virus and virus-like pathogens carried by the mother plants are major steps involved in clonal selection (Ulubelde et al., 1986) for the improvement of fruit crops.

Oil palm (Elaeis guineensis Jacq.) provides the highest oil yield per hectare among all oil crops (Corley and Tinker, 2008; Rival and Levang, 2014). Examining the global palm oil production statistics, which is extracted from the mesocarp of the oil palm, the total world production stands at 79.464 million tonnes. Indonesia leads the world production with 59%, while India ranks 13th with a production of 0.305 million tonnes, contributing insignificantly to the world palm oil production. Additionally, India imports about 19% of the world’s palm oil, accounting for 9.3 million tonnes, with a net worth of 11.7 billion U.S. dollars (USDA IPAD, 2024; Statista, 2024). In this challenging scenario, expanding the cultivation area of oil palm with high-yielding, disease-resistant, and dwarf statured varieties is imperative. The National Mission on Edible Oil-Oil Palm has set a target area of 27,99,087 hectares, but the achieved area is only 3,70,028 hectares (NMEO-OP). To meet this target, obtaining quality planting material is crucial. Traditionalvegetative propagation is not viable for oil palm due to its lack of axillary branching or axillary meristem. Given its highly cross-pollinated nature and long breeding cycle, obtaining true-to-type progeny is challenging. Therefore, the importance of propagation through in vitro mass multiplication techniques in this crop cannot be overstated.

Globally, India ranked second in vegetable production and contributed 15.8 and 14% to global vegetable area and production, respectively. The production of vegetables in India is estimated to be 212.91 million tonnes in the year 2022-23 compared to 209.14 million tonnes in the year 2021-22. India ranked first in production of okra in the world (73% of world production) and second in brinjal (27.55%), cabbage (13%) and tomato (11%). The major vegetable growing states in India are West Bengal (14.1%), Uttar Pradesh (11.4%), Bihar (9.3%), Madhya Pradesh (8.0%) and Gujarat (7.1%). Vegetables are especially important crops for farmers with small holdings because an appreciably higher income per hectare can be generated by growing vegetables than from conventional staple crops (Genova et al, 2006). However, vegetables are generally considered more vulnerable than staple crops to stressful environmental conditions including extremes of temperatures, drought, salinity, alkalinity, water logging, mineral nutrient excesses and deficiency (Chinnusamy et al, 2005). These environmental stresses are likely to be exacerbated by the prevalent climatic changes in many parts of the world. Among environmental factors, soil salinity stress is one of the main factor reducing production and productivity of vegetables in arid and semi-arid regions where irrigation water has excessive salt and annual rainfall is low. In India, about 6.73 million ha of land (~2.1% area of the country) is salt affected, out of which 2.96 million ha is saline and 3.77 million ha is sodic (Arora & Sharma 2017). About 75% of salt-affected areas exist in four states, i.e., Gujarat, Maharashtra, West Bengal, and Rajasthan (Mandal et al., 2018).

Introduction Vegetable crops are highly susceptible to biotic stresses indicated by disease causing micro-organism (fungi, bacteria, virus and phytoplasma). Indiscriminate use of chemicals for the control of diseases, insect pest have several disadvantages, particularly increased cost of cultivation, residual toxicity in food chain and development of resistance against pathogen. Management of diseases involves use of resistant varieties and integration of cultural and chemical control measures. Of the biotic stresses much of the breeding efforts have been directed towards developing resistance against diseases. In fact, breeding for resistance, has been one of the most important objective of vegetable breeder in the last half of the century. Genes that contribute to pathogen tolerance/resistance can be obtained from local germplasm resources, or through exotic lines, wild species or genera, or lines from other breedingprograms. In the biotechnological approaches for vegetable breeding also,  most of the achievement has been to generate transgenic plants resistance to disease. Often breeding for resistance has assumed greater importance in a number of vegetable crops. Major Diseases of Tomato Early blight: The casual organism is Alternaria solani. The symptoms appears as small, black spots with enlarged and concentric rings in a bull’s eye pattern in the center of the leaves. Tissue surrounding the spots may turn yellow. On fruits, dark brown concentric rings are seen that affects the market quality.

Vegetable crops belonging to the family Cucurbitaceae are known as cucurbits. These include 950 species in over 90 genera, mainly distributed in the tropics and subtropics (Schaefer and Renner, 2011). Enormous diversity of cucurbit genetic resources has evolved in past centuries to cater the nutritional requirements of people in different geographical and climatic regions. A large number of cucurbitaceous vegetables coming from different centres of origin are cultivated worldwide (Table 1). However, these crops are challenged by several biotic and abiotic stresses. Cultivated varieties are constrained by market demands, the necessity for climatic adaptations, domestication bottlenecks, and in most cases, limited capacity for interspecific hybridization, creating narrow genetic bases for crop improvement. Genetic resources are the building block for any crop improvement programme and includes landraces, traditional varieties, wild, weedy and other related species constituting primary, secondary and tertiary gene pools. They are valuable sources of important genetic traits needed for developing resilient and climate smart crop varieties and therefore, important for food security. The success and pace of the development depends on the efficient use of plant genetic resources. Wild relatives are incredible genetic resources carrying several desirable attributes like nutritional quality, resistance to biotic and abiotic stresses etc. Most of the crop wild relatives of cultivated crops across the world are not receiving adequate attention for their effective utilization in breeding programs. It is therefore, of utmost priority to protect them in the wild, through in-situ conservation, where they can continue to evolve and develop these useful adaptations. ICAR-National Bureau of Plant Genetic Resources (ICAR-NBPGR) is the nodal agency for the management of national wealth of vegetable genetic resources speciallyworking for collections, characterization, identification and documentation of new germplasm. Besides, it also bears the responsibility for conservation of the germplasm for future through sustainable use. The Vegetable germplasm is being conserved both under in-situ and ex-situ genebanks. This chapter highlights the status of Cucurbit genetic resources and procedures to access the germplasm by various stakeholders for research use.  

Okra (Abelmoschus esculentus Moench), known in many English-speaking countries as lady’s finger or gumbo, belongs to family Malvaceae. The geographical origin of okra is disputed and supposed to be South Asian, Ethiopian and West African origins (Anonymous, 20013a). Its proposed parents are reported to be in South Asian; therefore, it is believed that perhaps it is of South Asian origin. However, because of greater diversity in okra in West African region, it is considered to be originated in West Africa. Masters (1875) proposed that it originated in India. Okra is cultivated in tropical, subtropical and warm temperate regions, including the Middle East, Africa, Brazil, Turkey and southern states of USA (IBPGR, 1990; Jideani and Adetula, 1993; Acquistucci and Francisci, 2002). In tropics it is cultivated during summer and in the warmer parts of the temperate regions. It is an annual or perennial plant, growing up to 2 m height. The leaves are 10–20 cm long and broad, palmately lobed with 5-7 lobes. The flowers are 4–8 cm in diameter, with five petals which are generally yellow, but often white with a red or purple spot at the base of each petal. The fruit is a capsule which may attain length up to 18 cm containing numerous round seeds. Okra is an allopolyploid of uncertain parentage (proposed parents include Abelmoschus ficulneus, A. tuberculatus and a reported “diploid” form of okra).

India, internationally recognized as the principal producer, consumer and exporter of spices globally, is often referred to as the spice bowl of the world. A total of 75 spices out of 109 are cultivated in the country, among which pepper, cardamom, chillies, ginger, turmeric, coriander, cumin, and fenugreek are of significant importance. The approximate export of spices during 2021- 22 was 15,31,154 MT valued at 30,576.44 crore (US $4,102.29 million) compared to 17,58,985 MT valued at 30,973.32 crore (US $ 4,178.80 million) during the previous financial year. Indian spices are exported to more than 180 destinations, with the leading importers being USA, China, Bangladesh, Thailand, UAE, Sri Lanka, Malaysia, UK, Indonesia, and Germany. The key spice-producing states of India include Himachal Pradesh (ginger), Haryana (garlic), Karnataka (pepper, ginger, cardamom (small), chilli, turmeric and garlic), Orissa (ginger, chilli, turmeric, and garlic), Kerala (pepper, chilli, turmeric, nutmeg, mace, and clove) and Rajasthan (coriander, chilli, cumin, garlic, fenugreek, fennel, and ajwain). Seed Spices in Rajasthan Economy Of the 75 spices grown in India, 20 are classified as seed spices, where the economically important part is the seed.

Grape (Vitis vinifera L.) is one of the most valuable and popular fruit crops all over the world (Mohsen, 2021). In India, grapes are mainly grown for table, raisin and wine making. Major grape producing countries are China, Italy, France, Spain, USA, Turkey, and India while, major wine producing countries are France, Italy, Spain, and USA (OIV, 2024). According to an estimate, grapevine is spread on an area of 1.71 lakh ha and production was 37.81 lakh MT in the country during the year 2023-24 (NHB, 2024). India ranks first in world for grape productivity and 7th for grape production during 2023-24 (APEDA, 2024). Traditionally, grapes are grown on their own roots. However, due to deteriorating soil and water conditions, the use of rootstocks has become essential in the tropical climate of India to maintain production (Singh and Sharma, 2005). The grape industry which is important to produce wine and table grapes is facing  significant challenges due to changing climatic conditions. Climate change has led to increased temperatures, altered precipitation patterns, and more frequent extreme weather events, all of which can adversely affect grapevine health and productivity. To combat, the role of grape rootstocks has become increasingly vital for maintaining sustainable viticulture. Grape rootstocks are the belowgraft joint part of the grapevine onto which the scion variety is grafted. These rootstocks are typically derived from species of Vitis genus other than Vitis vinifera, the primary species used for grape production.