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Melons are annual plants that have up to three meters of climbing, creeping, or trailing vines. Several of them are consumed as dessert fruits while a few varieties/types are used for vegetable purposes. Generally, the fruits of commercial varieties are sweet, juicy, delicious with good nutritional and medicinal properties and a daily intake of 120-150 g can help in weight loss, better eye and skin health (Shivapriya et al., 2021).

Currently, muskmelon is being cultivated throughout the world, especially under tropical and subtropical climatic conditions. In India, muskmelon is grown in 54,000 ha with a production of 1.23 million tons (NHB, 2018). The estimated national seed requirement per year is about 27 tons with a value of about Rs. 27 crores. The crop is cultivated mainly in rabi season (November to February sowings), thus limiting its availability in the market during summer. Rarely, melons are cultivated for the off-season market, and those fetch a premium price. The total value of muskmelon fruits in the domestic market is estimated as Rs.1231 crores.

Watermelon (Citrullus lanatus (Thunb.) Matsum and Nakai) is an important cucurbit crop throughout the tropical and subtropical regions of the globe. It is an annual creeping vine and native to the Southern part of Africa, most probably the areas around the Kalahari Desert. Presently, more than 1200 cultivars have been developed and are being grown in nearly 122 countries with tropical and subtropical climates. Watermelon is mainly valued for its ripe ‘pepo’ fruits which are consumed as fresh-cut dessert or as juice. The fruits are a rich source of carotenoids, minerals, phenolic compounds, flavonoids, vitamin C and Citrulline, a non-essential amino acid. The red colour of the watermelon flesh is due to the presence of lycopene, the content of which is 40% more than that of tomato. Besides, there is good variation available for f lesh colour ranging from red, pink, yellow, orange, white and green. Owing to the ability to prevent several chronic diseases due to the presence of pigments like lycopene, anthocyanin, carotene, xanthophyll etc., presently watermelon is also considered as a functional food. The exocarp (rind) is also consumed as stewed, pickled or stir-fried or may be used for the preparation of ‘tooty fruity’. Watermelon seeds are considered a good omen and are gifted during Chinese New Year in East Asia. The seeds are also used in the baking and confectionary industries as these contain a characteristic nutty flavour. The seeds are also rich in protein, vitamins as well as omega-3 and omega-6 fatty acids.

Pumpkin (2n = 40) is an important ‘pepo’ vegetable of the Cucurbitaceae family. Five domesticated species viz., C. maxima, C. moschata, C. pepo, C. argyrosperma and C. ficifolia are included in the Cucurbita genera (Schaffer and Paris, 2003). Owing to the presence of maximum genetic diversity in the neotropical regions and its ability to grow in varied agro-ecological conditions and its tolerance to hotter climatic conditions as compared to the other cultivated Cucurbita species, C. moschata is known as “tropical pumpkin” (Andres 2004). In terms of the average nutritive values, pumpkin (2.8) stands at a higher position when compared to many widely grown vegetables. The fruits are rich in carotenoid pigments. However, the proportion of beta carotene is higher than the others. Beta carotene shows strong anti oxidative and anti-cancer properties. While, it has relatively low content of other carotenoids like alpha-carotene, lutein, zeaxantin and violaxantin (Matus et al., 1993; Fraser and Bramley, 2004). Moreover, pumpkin fruits are also rich in mineral elements viz., potassium, phosphorus, magnesium, iron and selenium. The mature pumpkin seeds contain the essential unsaturated fatty acids and minerals like zinc. Pumpkin-rich diet has also shown to have a pharmacological effect on reducing blood glucose (Xiong and Cao, 2001; Cai et al. 2003). Further, water-extracted pumpkin polysaccharides showed better hypoglycemic (Zhang and Yao, 2002). As a result, pumpkin has emerged as a staple food in many developing countries (Ferriol and Pico, 2008).

Ridge or ribbed gourd (Luffa acutangula (Roxb.)L.) is grown commercially and in homesteads for its immature fruits which are used as cooked vegetable. It is a popular vegetable both as spring-summer and rainy season crops. It is grown in tropical and subtropical countries, especially in Asia and India as an important cucurbitaceous vegetable crop (Jansen et al., 1993). The immature fruit is a rich source of dietary fiber and minerals (Sheshadri, 1990). Apart from culinary properties, it has vast medicinal properties which are traditionally used for the curing of stomach ailments and fever (Burkill, 1985; Chakravarty, 1990). The genus derives its name from the byproduct 'loofah', which is used in bathing sponges, doormats, scrubber pads, mattresses, pillows and in cleaning utensils. The tender fruits are prescribed for people suffering from malaria and other seasonal fevers because it is easy to digest and act as an appetizer. Ridge gourd contains 0.5g protein, 3.4g carbohydrates, 37mg carotene and 18mg vitamin C per 100g of edible portion. Some round varieties of ridge gourd are also used for stuffing purposes.

Ridge gourd is originated from India and is grown throughout the country by many of the small and marginal farmers for their regular income. Uttar Pradesh, Madhya Pradesh, Punjab, Chhattisgarh, Bihar, West Bengal, Maharashtra and all southern states like Andhra Pradesh, Telangana, Karnataka, Kerala and Tamil Nadu are the major states in India where ridge gourd is cultivated. It is grown in an area of 1.00 lakh ha in India with a productivity of about 10 12 t/ha which is very low.

Bitter gourd (Momordica charantia L.) is one of the important commercial cucurbitaceous cash crops grown mainly by small holding farmers in Asia where it is cultivated on more than 340,000 ha annually (McCreight et al., 2013). Eastern Asia, possibly Eastern India, or Southern China is most likely the center of origin for bitter gourd (Walters and Decker-Walters 1988; Miniraj et al., 1993). It is also known as bitter melon, bitter cucumber, balsam pear, bitter apple, or bitter squash (Morton, 1967). Fruits are known for abundant source of vitamins and minerals. Delicious preparations are made from fruits after stuffing and frying. It is also consumed in the form of Juice, Tea and Pills. Bitter gourd fruit abounds in phytonutrients (Dhillon et al., 2017) and often used to manage type 2 diabetes as a folk medicine. Clinical studies confirmed that elevated fasting glucose levels in pre-diabetics can be reduced by supplementing the diet with bitter gourd fruits. (Amirthaveni et al., 2018; Krawinkel et al., 2018). Medicinal properties present in the bitter gourd fruits are used in the curing of diabetes, asthma, blood diseases and rheumatism.

The current seed market of bitter gourd in Asia values ≈ 16 million Euros. The bitter gourd seed market in India alone is 400 metric tonnes having value of 350-400 crores. 70 % area is under hybrids and 30 % is covered by open pollinated varieties.

Okra [(Abelmoschus esculentus (L.) Moench] is one of the traditional vegetable crop cultivated in tropical, subtropical and warmer regions of the world. Okra fruits are rich in calcium (90 mg/100 g fresh weight) and provide valuable supplementary items in the tropical diet which is starchy in nature lacking calcium and iron. The root and stem are used for clearing cane juice in preparation of jaggery or ‘gur’. The high iodine content of fruits helps prevent goiter, while leaves are used in inflammation and dysentery. It has yet multiple uses. The dry seed contains 13-22 % good edible oil and 20-24 % protein. The oil is used in soap, cosmetic industry and as vanaspati, while protein is used for fortified feed preparations. The crushed seed is fed to cattle for increasing the milk production and the fibre is utilized in jute, textile and paper industries. India ranks first in the world with 7.16 million tonnes of production 5.49 lakh hectares of area. Gujarat is the leading okra-producing state which produces around 1147.66 thousand tonnes from an area of 93.95 thousand hectares followed by West Bengal. Fresh fruit of okra is exported to UAE, Sri Lanka, the Netherlands, Bangladesh, Malaysia, Nepal, UK, Saudi Arabia and Qatar. The national average productivity is very low (11.70 t/ha), that the crop is prone to damage by major biotic stresses like fungus, nematodes and viruses like Yellow Vein Mosaic Virus and Enation Leaf Curl Virus. The yield potential of okra is low; however, it could be improved through hybridization. Marked heterosis has been reported in okra for yield and its components.

Chilli (Capsicum annuum L.) and bell pepper (Capsicum annuum var. grossum) are economically significant crops in India, known for their distinct attributes and culinary uses. Despite their shared progenitor, these crops exhibit varietal differences and require specific breeding strategies for hybrid seed production due to small flower size. The development of male sterile systems has revolutionized hybrid seed production, with the exploitation of Genetic Male Sterility (GMS) and Cytoplasmic Male Sterility (CMS) in chilli and bell pepper breeding. The market for chilli seeds in India is substantial, driven by the demand for high-value hybrid seeds. This chapter comprehensively reviews the botanical characteristics, genetic resources, and breeding objectives in Capsicum species, emphasizing traits like disease resistance, high yield, and stress tolerance. It also highlights varietal achievements in public and private sectors, showcasing improved cultivars and hybrids with specific attributes. The integration of molecular markers in male sterile genes facilitates efficient hybrid seed production, ensuring genetic purity and quality. Additionally, the package of practices for seed production in chilli underscores the importance of isolation, field standards, inspection, harvesting, seed processing, and quality standards to maintain seed purity and viability.

Advances in seed production techniques have revolutionized brinjal cultivation, enhancing productivity, quality, and sustainability. Traditional methods, such as manual emasculation and pollination, have been supplemented and in some cases replaced by innovative approaches, contributing to increased efficiency and reduced labor costs. Cytoplasmic male sterility (CMS) and grafting technologies have emerged as valuable tools, offering novel avenues for enhancing breeding efficiency and managing soil-borne pathogens. These advancements have facilitated the development of high-yielding F1 hybrids and improved pure-line varieties with enhanced resilience to pests and diseases. Furthermore, the adoption of precision agriculture techniques, including controlled environment agriculture and hydroponics, has enabled year-round seed production, mitigating the impact of seasonal fluctuations and adverse weather conditions. Integrated pest management (IPM) strategies have been integrated into seed production protocols, minimizing chemical inputs and promoting environmentally sustainable practices. Additionally, innovations in seed extraction methods, such as mechanical extraction and dry extraction techniques, have streamlined the seed processing workflow, resulting in higher seed purity and improved germination rates.

Tomato (Solanum lycopersicum L.) is one of the most commercially important vegetable crops globally, with a significant demand for high-yielding hybrids and improved open-pollinated varieties. Efficient seed production methodologies play a crucial role in ensuring the availability of genetically pure and high-quality seeds for commercial cultivation. Traditional hand emasculation and pollination remain widely used despite being labor intensive, given their economic feasibility due to high seed yield per fruit. Hybrid seed production is further refined through mechanized pollen collection and controlled pollination techniques, enhancing efficiency. Seed quality management, including rigorous isolation protocols, field inspections, and breeder and foundation seed production standards, ensures genetic purity and viability. Advances in molecular breeding and the application of marker-assisted selection (MAS) have enhanced the efficiency of parental line development and hybrid seed production. This chapter provides an in-depth review of tomato seed production methodologies, covering botanical characteristics, genetic resources, and breeding objectives aimed at improving disease resistance, abiotic stress tolerance, and fruit quality traits. It further discusses varietal advancements in the public and private sectors, highlighting elite hybrids and open-pollinated cultivars tailored for different agro-climatic conditions. Additionally, the package of practices for seed production in tomato underscores the importance of isolation, field inspections, seed extraction methods, processing techniques, and quality assurance standards to maintain genetic purity and seed viability.