snake gourd

seed production technology of snake gourd

1. Seed production technology of snake gourd Vanisree Padmanabhan 2019534005

2. Introduction Snake gourd is a tropical or subtropical vine crop raised for its long fruit. It is cultivated across south and south-east Asian countries. It produces greenish white and whitish color fruits that develop into 100-150cm in length and 60-75cm in diameter. It is suitable for growing for home garden and fresh market.

3. Scientific classification Kingdom: Plantae (unranked): Angiosperms (unranked): Eudicots (unranked): Rosids Order: Cucurbitales Family: Cucurbitaceae Genus: Trichosanthes Species: T. cucumerina Binomial name: Trichosanthes cucumerina L. Synonyms: Trichosanthes anguina L.

4. Species of Trichosanthes : Trichosanthes contain totally 44 species, out of that 21 sp.,occur in India. Trichosanthes has 2 cultivated sp T. anguina T. dioica • Origin - Indo Malayan region. Classification by kundu(1942) & chakravarthy(1982), Genus is divided into 2 section 1.Eutrichosanthes-23 species 2.Pseudotrichosanthes-3 species

5. The species of snake gourd include; Trichosanthes cucumerina var.anguina -cultivated variant Trichosanthes cucumerina var.cucumerina -wild variant Trichosanthes cucumeroides- Ja panese snake gourd Trichosanthes kirilowii var.japonica – grown for root starch. Some of the common names of snake gourd are; Serpent gourd Chichinda Padwal

6. Uses of snake gourd As vegetable Snake Gourd is grown principally for the immature fruit that can be cooked Can be served as a vegetable like zucchini squash As medicine Roots and seeds are used to expel worms and to treat diarrhoea and syphilis acts as an excellent anti-inflammatory makes digestion easy

7. Botany of snake gourd It is a monoecious annual vine climbing by means of tendrils. Leaves are palmately lobed, up to 25cm long. Flowers are unisexual , white, opening at night , with long branching hairs on the margins of the petals. These hairs are curled up in the day time when the flowers are closed. But unfurl at night to form a delicate lacy display.

8. contd.. Calyx - Sepals 5, gamosepalous, imbricate aestivation. Corolla - Petals 5, gamopetalous, margin of each petal ends in hair like structure, a special out growth are found on the petal called papilla • Androecium -3 stamens united filaments free. • Gynoecium - Superior ovary , parietal placentation where ovules develop on the wall or slight outgrowths of the wall forming partitions.

9. Fruit Fruits can be up to 200cm long , deep red at maturity, hanging below the vine. Narrow and longish fruit can grow more than 150 cm (5 feet) in length. Dark green with several light green lines or totally white. It is soft and breaks easily when bend. Numerous seeds,relatively large and slightly gray. When it is fully ripe, the fruit pulp turns red.

10. Floral Biology Flowering normally starts in about 40-45 days. Flowers being auxiliary and the sequence of flowering follows a set pattern, namely, the first 4-6 flowering nodes bear staminate flowers and later pistillate flowers appear on the main axis and secondary branches. The sex ratio ranges from 25-30:1 to 15:1 . Influenced by high temperature, long days and high N, promoting more number of staminate flowers .

11. Sex forms Hermaphrodite sex is considered as primitive form, where only bisexual flowers are present. The advanced sex form is monoecious , where staminate and pistillate flowers are produced separately in the same plant. Sex modification Venkatram(1967) reported beneficial effect of increased female flower production by application of TIBA, NAA and MH (200-500 ppm)where MH was effective.

12. Anthesis and Pollination Anthesis takes place at early hours of the night and anther dehiscence occurs simultaneously. Pollen grains remained viable 49-56 hours after dehiscence. Stigma remained receptive from 20 hr before anthesis to 51 hr after opening. It is cross pollinated where the extent of cross pollination very from 60-80 per cent.

13. The pollination is entomophilous and mostly by bees . For maximum fruit set and seed yield, availability of pollinators is a prerequisite. One bee colony per half hectare would be required for seed production plots.

14. SEASON Seed crop should always be raised in seasons, which remain dry at the time of seed maturity and seed extraction. Summer season is preferred over rainy seasons for raising seed crop. Region of seed production: Deccan plateau of Telangana, north Karnataka and Eastern Maharashtra and small parts of Tamil Nadu are the regions of snake gourd seed production.

15. Seed rate and planting Pits are spaced at 1.5-2.0m in rows and dug at 0.75m depth. Seed rate about 2.5g/ha. SPACING long vined- Intra row-2m and Inter row -2m short vined - Intra row-1.5m and Inter row-1.5m It is cultivated by trailing on bower and pandals erected at height of 1.5-2.0m Grows more vigorously and produces heavy yield a strong bower would withstand weight of fruits and foliage.

16. Manures and Fertilization Application of FYM of about 130kg/ha. 250kg Neem cake, 5kg Azospirillum, 5kg Phosphobacteria and 6-7 kg of Pseudomonas applied per hectare. N,P,K is applied at the rate of 180:240:250 kg at the cropping period. About 90kg of N applied at basal and remaining as top dressing. Spraying of Ethrel 200-250ppm at two true leaf stage and after a week of 1 st spray helps increase female flowers .

17. Isolation Under seed Act , It is the minimum isolation distance that has to be maintained to separate the seed production plot, from the fields of other variety , fields of same variety not conforming to varietal purity requirements for certification or wild cucurbit species and other contaminants.

18. Isolation requirements Contaminants Foundation seed(m) Certified seed(m) Open pollinated varieties Fields of other variety 1000 500 Fields of same variety not conforming to varietal purity requirements for certification 1000 500 Hybrids 1500 1000

19. Field Inspection The objective of field inspection is to eliminate the off-types for maintaining genetic purity. Rouging ( removal of off-type plants) at different stages are essential. The stages are: Before flowering At the time of flowering Fruit development stage Marketable or edible maturity stage of fruit

20. contd.. In case of hybrid seed production , at least four inspections are necessary : i) Before flowering to ensure isolation , to detect volunteer plants , demarcate seed parents and pollinator block i.e.to determine the planting ratio. ii) and iii) Flowering and fruiting stages to check isolation, off-types, pinching of male bud in seed parent block iv) At maturity to verify true internal fruit characters.

21. Genetic Purity and seed health standards Factor Maximum permitted Level(%) Foundation seed Certified seed Open pollinated varieties Off –types 0.10 0.20 Objectionable weed plants None None Hybrids Off-types in seed parent, pollinator parent, pollen shedders in seed parent(male sterile) 0.01 - - 0.05 0.05 0.10

22. Varieties of snake gourd KONKAN SWETA Developed at KKVP, Dapoli. Fruits 90-100 cm long, having whitish surface with green stripes. Suits growing in Konkan regions of Maharashtra. Yields about 25-27t/ha in 125-130 days.

23. CO-1 It is a selection, bearing long fruit 60-180cm with white stripes, weighing 500-750g. Yields about 18 tonne/ha with a duration of 135 days. CO-2 It is a selection , bearing short fruits(30 cm length), light greenish white. Yields about 35 tonne per ha, with a duration of 105-120 days. Suitable for high density planting .

24. PKM-1 A mutant with crop duration of 145 days. Fruit weighs about 500-800 g with length of 155-170cm. Yields about 24t/ha. MDU-1 Hybrid between a long fruited selection 1 and a short fruited pannipudal . Plant is less spreading. Fruits green with white stripes and medium in length(70cm). Yields about 32t/ha in 143 days.

25. APAU Swetha Developed by APAU, Hyderabad. Fruits long having whitish background with green stripes. Yield 28t/ha in 125-130 days. TA 19 It is new collection recommended by the KAU. Fruits are about 60cm long. At immature stage they are light green with white stripes at the styler end. Average fruit weight 600g and the fruits are ready in 65-70 days from sowing.

26. MANUSREE Developed by KAU. Uniformly white and medium long(67.72 cm), cylindrical fruits with green markings at the pedicel. Av.fruit weight 775.0 g. yields around 32.5t/ha. PLR(SG) 1 Pure line selection from white long type is suitable for cultivation under irrigated condition. Fruits has excellent cooking quality due to less fibre and high flesh content and does not twist due to maturity.

27. PLR( SG) 2 Excellent cooking quality due to less fibre content . Fruits plumpy with attractive flesh colour. Single fruit weighs 600 g. Short fruit enables easy transportation.

28. Maturity It takes relatively less time for maturing compared to other cucurbits. The maturity is also influenced by environmental conditions and crop management. The physiological maturity is observed where 1/3 of fruit tip changes from yellow to red. Snake gourd takes around 65 days for maturing.

29. Seed Extraction Seed extraction in snake gourd is done by dry method. The dried fruits are cut from one side and the seeds come out from the fruit. Seeds are kept in soaked condition for overnight that helps faster germination. Seeds soaked in 2% Bavistin for 6-8months helps control fungal diseases. Fruit to seed recover is about 15-16% Seed yield of snake gourd ranges from 220-250 kg/ha.

30. Seed Storage Seeds stored should have moisture content not more than 6-7 per cent. Dry seeds stored in air tight containers at about 5⁰C and 25% relative humidity. Silica gel can be added to absorb moisture. Seed viability lasts for more than 5 years .

31. Seed Borne Diseases Virus diseases like SqMV,CMV,CGMMV are carried through seeds. Bacterial pathogens like Pseudomonas syringae - Angular leaf spot Xanthomonas campestris -Bacterial leaf spot are seed borne. At the time of field inspection thorough checking of diseased plants and their immediate removal along with fruit is enforced.

32. Hybrid seed production Three steps are involved in F1 hybrid seed production; 1.Development of inbred lines and their production 2.Testing of combining ability 3.Production of F1 hybrid seed. Techniques of hybrid seed production: Hand emasculation and hand pollination Hand emasculation and insect pollination

33. contd. In snake gourd hand pollination is widely adapted. One pollination/fruit gives a high seed recovery of 200-300 hybrid seeds per fruit. The male and female plants grown in isolation and male plant sown 15 days earlier than female plant. During pollination and fruit set any off-types identified are removed from male parent. When female parent flowers hand pollination is done and covered after crossing.

34. contd.. Male buds are collected and moistened and stored overnight for use in next day. Pollination is done using two male flowers on the stigma of female parent by thoroughly dusting on the stigma lobes. Enough to have 3 fruits (crossed) set per vine and allowed for fully maturity.