Everything you need to know about bottle gourd cultivation, production and harvest. Learn about:- 1. Introduction to Bottle Gourd 2. Origin of Bottle Gourd 3. Composition and Uses 4. Climate Required for Cultivation 5. Soil Required for Cultivation 6. Sowing Time 7. Riverbed Cultivation 8. Manurial Requirement for Cultivation 9. Irrigation Requirement for Cultivation 10. Intercultural Operations 11. Harvesting and Yielding 12. Cultivated Varieties.
Contents:
- Introduction to Bottle Gourd
- Origin of Bottle Gourd
- Composition and Uses of Bottle Gourd
- Climate Required for Cultivating Bottle Gourd
- Soil Required for Cultivating Bottle Gourd
- Sowing Time of Bottle Gourd
- Riverbed Cultivation of Bottle Gourd
- Manurial Requirement for Bottle Gourd Cultivation
- Irrigation Requirement for Bottle Gourd Cultivation
- Intercultural Operations of Bottle Gourd
- Harvesting and Yielding of Bottle Gourd
- Cultivated Varieties of Bottle Gourd
1. Introduction to Bottle Gourd:
Bottle gourd, also known as white-flower gourd, is an important warm season cucurbitaceous crop of India. It is also commonly grown in Africa, Central America, Ethiopia, and other warmer countries of the world. In India, it is extensively grown as spring-summer and rainy season crop in all the tropical and subtropical dry areas. It is a modest source of nutrients even then it is popular among a large section of people. The precise data on area and production are not known, however, it has some share in gourd vegetables, which is about 4.05 lakh hectare.
Its fruits having variable shapes- cylindrical, long, oblong, round, or round-oval depending upon the variety, size ranging from 10 to 100 cm and light green to dark green in colour are available in the market throughout the year. The fruit at immature stage is soft in texture with white pulp and large white tender seeds. Light green to dark green straight fruits of bottle gourd having 30- 40 cm length are exported to South-East Asia and Gulf countries.
2. Origin of Bottle Gourd:
New genetic and archaeological approaches have substantially improved our understanding of the transition to agriculture, a major turning point in human history that began 10000 years ago with the independent domestication of plants and animals in eight world regions, however, in the Americas understanding, the initial domestication of New World species has long been complicated by the early presence of an African enigma, the bottle gourd (Lagenaria siceraria).
Indigenous to Africa, it reached East Asia by 9,000-8,000 before present (B.P.) and had a broad New World distribution by 8,000 B.P. Here, we integrate genetic and archaeological approaches to address a set of long-standing core questions regarding the introduction of bottle gourd into the Americas. Fruit rind-thickness values and accelerator mass spectrometer radiocarbon dating of archaeological specimens indicate that the bottle gourd was present in the Americas as a domesticated plant by 10000 B.P., placing it among the earliest domesticates in the New World.
Ancient DNA sequence analysis of archaeological bottle gourd specimens and comparison with modern Asian and African landraces identify Asia as the source of its introduction. It is suggested that the bottle gourd and the dog, two utility species, were domesticated long before any food crops or livestock species, and those both were brought to the Americas by Paleo-Indian populations as they colonized the New World.
Bottle gourd has been found wild in India, Moluccas, Ethiopia, and South Africa. However, it is probably indigenous to tropical Africa based on variability in seeds and fruits. This species appears to have been domesticated independently in Asia, Africa, and New world. In some literature, it is mentioned that the center of origin has been located as the coastal area of Malabar (North Kerala) and humid forests of Dehradun (North India). It has spread to western countries from India and Africa.
The fossils record indicates its cultivation in India even before 2000 BC. It has been used by man in the new world for at least 12,000 to 15,000 years back. The bottle gourd was one of the first plants to be domesticated in America. Occurrence of considerable diversity in the morphology of fruit in archaeological sites suggested a steady influx of new germplasm from outside the immediate area. It is now widely spread throughout the tropics.
3. Composition and Uses of Bottle Gourd:
Composition:
Bottle gourd contains protein, fat, minerals, like phosphorus, iron, and potassium and many of the vital amino acids required in our diet. The fruits contain carbohydrates 2.9%, protein 0.2%, fat 0.5%, and vitamin C 11 mg/100 g fresh weight. The cellulose and lignin contents of bottle gourd leaves were highest at 91.06 and 76.09%, respectively.
The phenol contents increased in healthy fruits up to the 5th day and then declined, whereas, in Botryodiplodia theobromae inoculated fruits the phenols greatly increased up to the 10th day, decreasing thereafter. Even so, at the 15th day the increase was 416.6% over the uninoculated control. The nutritive value of 100 g of edible portion is given in Table 8.1.
Uses:
Fruits at immature tender stage are used for making various types of vegetable curries as boiled or fried, and confectionaries such as sweetmeat, Burfi, Kheer, and Rayata, and for making pickles as well. Kofta is the most popular preparation. Bottle gourd is grated, and boiled pulp added to the curd makes very nutritive, refreshing, and cooling drink in summer months.
The hard dry shell of the fruit is used for making different articles of common use, including bowls, bottles, ladles, containers, floats for fishing nets, pipes, and musical instruments. In addition, the seed kernels and seed oil are edible.
Medicinal Uses:
Besides pulp, its young stem and leaves have many medicinal values. Being easily digestible, it is the best vegetable for the patients suffering from various stomach disorders. It is often included in the diet of old and convalescing patients. It has certain curative properties like cooling, diuretic, and sedative. The pulp of cultivated varieties fruits is a cardiac tonic, good for overcoming cough and used as adjunct to purgative. It also acts as an antidote against certain poisons.
The bitter fruit ash mixed with honey is a useful application to the eyes for night blindness. It is good for people suffering from biliousness and indigestion. The plant extract is used as a cathartic, and the seeds are used in dropsy. It is known to calm the nerves, and removes chronic constipation. It is especially recommended in the diet of patients suffering from high blood pressure. It is a useful remedy to cure the urinary disorders.
A glass of its juice mixed with 5-10 ml juice of lemon if taken daily can relieve the burning sensation in the urinary passage often caused by hyperacidity because it serves as an alkalinizer. If it is taken with a pinch of salt, it can control severe diarrhea. A decoction made from the leaf is a very good medicine for curing jaundice. The seed oil forms an emollient application for the head, and is applied to the head to relieve headache.
Rahman (2003) also explored the scientific credibility of narration of bottle gourd in the scriptures of the world and traditional usage, described the biological activities of bottle gourd on human body, and emphasized that bottle gourd is having the high therapeutic values, and hence, must be consumed as daily nutrition.
4. Climate Required for Cultivating Bottle Gourd
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Bottle gourd is a warm season crop and cannot tolerate frost and strong winds. Emergence ceased at 45°C and seedlings emerged above 15°C in bottle gourd. The optimum temperature range for seedling emergence was narrower for vegetables than for cereals. The vines grow well at a day temperature between 25° and 35°C but the optimum temperature for growth is 24-27°C.
Low temperature coupled with short days and humid climate favour the development of pistillate flowers. High rainfall with prolonged cloudiness leads to higher incidence of foliar diseases and in turn drastically reduces the crop yield. In temperate countries, bottle gourd is grown in glasshouses or polyhouses where carbon dioxide, temperature, humidity, and light are maintained according to crop requirement and the plants are trained with the help of plastic twines.
In bottle gourd, fruit number, fruit length, and fruit yield showed almost similar trends where respective values at 100 and 75% PARs were similar, but both values were significantly (P < 0.05) higher than the other light treatments. Fruit weight was the highest at full light and then steadily declined as the light level decreased.
5. Soil Required for Cultivating Bottle Gourd:
Bottle gourd can be grown on all types of soils, however, well-drained organic matter rich sandy loam soil having good water retention capacity is considered best for its cultivation. The soil should be deep enough to support the growth of vines for a longer period. The soil temperature for good plant growth is 18-22°C. The soil should not crack in summer and waterlogged in rainy season since both the conditions are very harming to bottle gourd plants. The plants of this crop are sensitive to acid soils and the most preferable soil pH range is 6-7. Bottle gourd cannot be grown successfully in soils having pH below 5.5.
Fly ash emanating from the thermal power plant, in Kasimpur, India, influenced various physicochemical properties of the soil, which favored the growth parameters (such as plant length, fresh and dry weights, net primary productivity, leaf area, and photosynthetic pigments) of bottle gourd and subsequently controlled root rot incidence caused by the fungus Rhizoctonia solani.
Incorporation of fly ash into the soil at 10% reduced the fungal growth by 25% and caused significant improvement in plant growth parameters. The local cultivars ‘Hapcheon’ and ‘Cheongdo’ showed 75% or higher emergence rate in salty soil having electrical conductivity (EC) value of 3.0 dSm-1, whereas, most of the imported accessions failed to show any emergence at EC 3.0 dSm-1.
When seedlings having 2 expanded leaves were transplanted into soils having different EC values adjusted with a commercial compound fertilizer (N : P : K = 21 : 17 : 17), Hapcheon exhibited only slight growth inhibition even in soil with EC value of 3.0 dSm-1. Hapcheon exhibited good tolerance to Phytophthora root rot (Phytophthora drechsleri), suggesting the possibility of selection for salt tolerance as well as for Phytophthora root rot resistance from the local bottle gourd collections.
6. Sowing Time of Bottle Gourd:
Being a crop of tropical group, bottle gourd is grown in both spring-summer and rainy season. However, it can be sown in winter also to get early spring-summer crop. In South and Central India where winter is neither severe nor long bottle gourd can be raised throughout the year, however, the crop sowing is usually done in October-November and matures in March-April. In general, in northern India, bottle gourd is sown early in the riverbeds in November and extending to February-March in garden lands.
The spring-summer crop is sown in last week of February to first week of March and rainy season crop in June-July. To catch early market the farmers do the early sowing in November and protect the plants against frost with sarkanda cover. In plains of northeastern India, it is grown from November to March when weather is comparatively dry. In the hills of northern India, sowing of bottle gourd starts from April-May and crop matures in August.
Thind (1972) reported that when sprouted seeds were planted in December and January emergence was almost complete after 25 days, whereas, emergence from unsprouted seeds had just begun, and the seedlings with 3-5 leaves transplanted at the end of February produced harvestable fruit after a month, 35-45 days earlier than direct seeding and 30 days earlier than seeding with sprouted seeds.
Sowing on 17 March gave the greatest number of fruits (48 286/ ha) and the highest yield (38.0 t/ha) and fruit weight (0.83 kg/fruit), whereas, sowing on 15th June gave the lowest number of fruits (25 517), yield (19.7 t) and fruit (0.7 kg) weight.
Sowing Method:
Bottle gourd is propagated through seeds, and in most of the places, direct sowing is done. Normally, sowing in raised beds is followed in most of the places since this practice saves irrigation water apart from intercultural operations, which can be performed during early growth of vines. In general, furrows about 20-25 cm deep are made at a distance of 2.0-2.5 m and sowing is done on both the raised edges of furrow keeping a distance of 60-75 cm between plants.
This practice allows the vine to spread over the raised portion of the beds where water is not allowed to flood-over as such the water will not touch and spoil the developing fruits. Spacing the plants at 300 x 45 cm with one plant/hill gave the highest average yield of 384.54 q/ha.
The seeds are sown in polyethylene bags of 15×10 cm size to get an early crop, and the seedlings as and when attain 2-true leaf stage are transplanted in the main field after removing the polyethylene bag gently without breaking earth ball since bottle gourd may not normally withstand transplanting beyond this stage due to injury to the taproot. Following this practice saves seeds by 50-60% as compared to in situ sowings.
In case, the crop is transplanted from the nursery grown in polyethylene bags, pit planting is recommended. For this purpose, the 30 cm deep pits of 30 cm diameter are dug up at recommended spacing and added with a mixture of farmyard manure and chemical fertilizers. The seedlings raised in polyethylene bags are then carefully placed in pits and filled with the taken out soil. The plants raised in polyethylene bags or direct-sown under cover gave the highest early and total yields.
The seeds being hard enough are soaked in tap water for about 12-24 h, depending upon temperature for improving germination. Pre-sowing soaking of seeds in solution of succinic acid (600 ppm) for 12 hour also improves the seed germination. Germination was induced in bottle gourd seeds in winter by wrapping them in fleshy Calotropis procera leaves, exposing the parcels to sunshine and keeping them warm at night for 6 days.
Other treatments involving soaking in GA and/or incubation at 26-28°C, wrapped or not, were less successful. Germination of bottle gourd was reduced when the nematode + R. solani, R. solani alone, or the culture filtrate were added to sterile soil sown with seeds soaked in the filtrate. Nematode penetration and disease incidence were reduced more when both pathogens were added together than with either alone.
Root inhibition, reduction in germination and reduced larval penetration may have been due to toxins in the filtrate. In bottle gourd seeds, the emergence rate was significantly reduced by the presoaking treatment. Low temperature storage of bottle gourd seeds after imbibition was effective for increasing the percentage of healthy seedlings for grafting, possessing short and thick hypocotyls.
In winter season, the bottle gourd performs better under coconut shade. Bottle gourd should not be fitted in cropping sequence with other cucurbits due to potential for disease carryover. Rotation with peanuts, chilli, and tomato should also be avoided. Rotation with rye, wheat, or small grain crops is ideal although other non-cucurbitaceous crops are acceptable. It is advisable not to plant bottle gourd in fields where herbicide carryover from previous crop can be a problem.
Among the summer crops, bottle gourd and onion intercropped with potato performed better compared to sesame or sunflower in terms of potato equivalent yield and bottle gourd cropping increased DTPA extractable iron and manganese in soil. The yield of maize and bottle gourd crops intercropped with potato was recorded maximum compared to other crops raised under different irrigation methods.
Seed Rate:
Bottle gourd seeds are bit larger than other cucurbits, and the number of seeds per 100 g weight is 400-500, hence, per unit area comparatively more quantity of seed is required. Seeds can be kept viable for 3-4 year without any serious loss. About three to five kilogram seeds are sufficient for the sowing of a hectare area.
7. Riverbed Cultivation of Bottle Gourd:
The practice of growing vegetables in riverbeds is usually followed by the vegetable growers in northern plains of India, especially in Sutlej area. The sowing is done in winter that helps in raising the crop early. The crop is sown in pits or trenches made east west at a distance of 2.5- 4.0 m. The depth of trenches depends upon the retention of soil moisture. The trenches before sowing seeds are filled with a mixture of soil and well-composted farmyard manure in equal proportion.
In the month of December and January when the temperature goes below 1-2°C, the protection is provided by inserting lower end of sarkanda grass (Saccharum sp.) into the soil on northern side of trench and giving an angle of 75°. The crop so produced is about a month earlier than the normal ones and farmers fetch very high price of the produce in the market. Pandey et al. (2004) compared the growth and yield of bottle gourd grown under open and polyhouse conditions.
8. Manurial Requirement for Bottle Gourd Cultivation:
The quantity of manure and fertilizers required for raising a healthy crop of bottle gourd depends upon the soil type, season of cultivation and climatic conditions of the growing region. It is difficult to be specific about fertilizer recommendation as cultivation system of bottle gourd varies in different areas. In riverbed system of growing cucurbits and in areas where pit sowing is the most common practice, the farmyard manure is applied in trenches and pits, respectively.
The quantity of farmyard manure in each pit varies from 2 to 3 kg followed by thorough mixing. A small quantity of nitrogenous fertilizer is also applied at this stage. This can also be supplemented with phosphatic and potassic fertilizers. At the time of removal of Sarkanda cover, another dose of nitrogenous fertilizer is also applied to each plant followed by weeding and hoeing.
In the situations where plants are raised in polyethylene bags to get early yield, the beds are prepared at a distance of 2.0 to 2.5 m. Then a little soil is taken out of the pits prepared at a distance of 60-75 cm on both sides of the raised bed. A mixture of one kilogram of well- decomposed farmyard manure, about 15-20 g of calcium ammonium nitrate (CAN), 25-30 g of single super phosphate and 15-20 g of muriate of potash is added in each pit and mixed thoroughly.
Another dose of nitrogen (15-20 g CAN or 7-8 g urea per plant) is given to the plant during early stage of crop growth. However, the quantity of fertilizer varies with the soil type and growth of vines. This practice saves a good amount of fertilizer, thus, it is considered the most economical for the growers.
Increasing rates of nitrogen from 0 to 120 kg/ha fertilizers increased N, P, and K uptake and chlorophyll ‘a’ and ‘b’ and total chlorophyll content. The highest N, P and K uptake values (53.01, 10.48 and 41.48 kg/ha), and chlorophyll ‘a’, chlorophyll ‘b’ and total chlorophyll contents (0.682, 0.618 and 1.508 mg/g, respectively) were obtained with nitrogen 120 kg/ha. Nitrogen applications significantly affected dry matter accumulation in the vines, fruits, leaves, and roots and N accumulation in the leaves of bottle gourd cv. Arka Bahar.
In places where direct sowing is done, it is advisable to apply farmyard manure 25-30 t/ha at the time of land preparation and mix thoroughly with repeated pre-sowing cultivations. Among the chemical fertilizers, application of nitrogen 56 kg/ha was optimum, while application of phosphorus and potassium was uneconomical as reported by Malik (1965) who recommended nitrogen 56 kg, phosphorus 28 kg and potassium 28 kg/ha.
On the contrary, Mehta (1969) suggested nitrogen 95 kg/ha for a good yield of bottle gourd. Some other scientists recommended nitrogen 40-60 kg, phosphorus 40-60 kg and potassium 60-80 kg/ha.
As per the recommendation of Punjab Agricultural University, Ludhiana, farmyard manure is applied 50-60 t/ha at the time of land preparation, the half of nitrogen (40 kg/ha) through band placement at the time of sowing, and the rest half of nitrogen after 25-30 days within the furrows followed by earthing up since this practice helps better utilization of fertilizers. Bottle gourd does not require too much fertilizers so no phosphorus and potassium is recommended by the Punjab Agricultural University, Ludhiana.
Phosphorus increased the uptake of nutrients but did not affect the chlorophyll content. The highest N and K uptake (40.66 and 36.16 kg/ha) was obtained with phosphorus 50 kg/ha, while the highest P uptake (11.14 kg/ha) was obtained with phosphorus 100 kg/ha. Phosphorus also showed positive influence on dry matter accumulation in the vines, fruits, leaves and roots, whereas, phosphorus application had no significant effect on the various characters.
Potassium fertilizer did not affect the P and K uptake and chlorophyll levels but increasing rates increased N uptake. Nitrogen uptake was highest (39.43 kg/ha) with the application of potassium at 30 kg/ha.
The yield of bottle gourd was higher at high fertility (CAN : SSP : MOP = 150 : 100 : 45 g/pot of 45 x 45 x 45 cm) level. The average yield of bottle gourd cv. Arka Bahar was 385.37 q/ha with full dose of NPK (180 : 100 : 100 kg/ha) and 300.74 q/ha with reduced dose, i.e., one-third of the full dose. Application of NPK 120 : 100 : 30 kg/ha recorded the highest yield and appeared to be the optimum fertilizer rate for bottle gourd cv. Arka Bahar under southern dry conditions.
9. Irrigation Requirement for Bottle Gourd Cultivation:
Irrigation in bottle gourd depends upon the type of soil and method of planting. In riverbed cultivation, the spot application is given with pots during early growth period and is stopped when roots touch the subterranean moisture zone. In direct sown crop during spring season, furrow irrigation before sowing is given and seed is sown at the level of available moisture.
As seed coat of bottle gourd is thick, germination has to be ensured by mulching that prevents moisture loss through evaporation. Generally, the seeds presoaked overnight in water are sown to improve percent germination, and crop is irrigated at 5-6 days interval since soil moisture that should be at least 10-15% above the permanent wilting point is important for rapid vines growth, though, over irrigation should be avoided as it leads to development of foliar diseases.
As far as possible, the beds or inter rows should be kept dry to avoid decaying of developing fruits, however, it is not possible to keep the beds dry in rainy season. The incidence of anthracnose and fruit fly is severe if microclimate near the vines is humid, thus, the progressive farmers train the vines over trellis, or pandals at a height of 1.5-2.0 m to prevent decaying of fruits.
Being a summer crop, bottle gourd needs more irrigation at short interval. Drip irrigation system may help in conserving water, increasing water use efficiency and reducing irrigation need with higher yield.
Being a widely spaced crop, drip irrigation is found to be economical for this crop since the crop yield through this system is about 48% higher than the yield received through furrow irrigation. This method of irrigation plays an important role in improving the economy in areas having limited water resources. Moreover, this system may help in controlling weeds, and it can be used for fertigation along with drip irrigation.
The longest main vine (579.8 cm) and the highest number of branches per plant (7.85) were obtained with 125% CPE and the highest number of fruits per plant (356.1) with 100% CPE through drip irrigation. Drip irrigation at 125% CPE gave the highest fruit yield—325.2 q/ha. Growth, yield attributes, and yield of bottle gourd increased significantly due to supplemental irrigation from the water harvesting structures compared with rain fed control. The net return and benefit: cost ratio also increased.
Irrigation at 25, 35, and 45 mm CPE recorded a lower number of node to appearance of first male flower and days to appearance of first female flower than irrigation at 55 mm CPE. Substantial increase in the number of female flowers and decrease in sex ratio were observed with irrigation at 25 or 35 mm CPE.
Increasing irrigation water salinity levels (0.3, 3, 6 or 9 dSm-1) resulted in decreasing yield of bottle gourd. The yield of bottle gourd was highest for best available water (192.2 q/ha) and decreased with increasing salinity (2, 4, 6, 8, 12 or 16 dSm-1) of irrigation water. A 50% reduction in yield occurred at a salinity of EC 10.8 dSm-1, and this may be regarded as the threshold value for bottle gourd.
It is concluded that the use of saline water of up to EC 4 dSm-1 may not cause any deleterious effect on crop yield or the properties of the sandy loam soil. Sewage-irrigated bottle gourd showed higher nutrient uptake than tube-well watered bottle gourd. Plants with well-defined reproductive or fruit-bearing parts showed sufficient accumulation of nitrogen, phosphorus, potassium, iron, copper, manganese, and zinc tested.
10. Intercultural Operations of Bottle Gourd:
i. Hoeing and Weeding:
Bottle gourd is a widely spaced crop, thus, weeding and hoeing during early stages of vines growth can be done mechanically with tractors or bullocks drawn hoe. In later stages of crop growth, weeding is not recommended as the vines with bigger size foliage smother the weeds, hence, are not a serious threat to the crop, however, the tall weeds that appear in the later stages of crop growth are uprooted manually.
Retaining weeds in later stages in spring-summer months is rather useful since they provide protection to the developing fruits against sunscald disorder sometimes developed due to exposure to blazing sun. The weeding and earthing that are done at the time of application of second dose of nitrogenous fertilizer also helps in checking the weeds.
In bottle gourd, usually no weedicide is recommended to keep the weeds under check yet non-selective contact herbicide such as paraquat (Gramexone) can be applied as protected spray only on raised portion before the vines cover the beds if the weeds intensity is too high, however, precautions should be taken to avoid the drift of chemical onto the crop plants while spraying the chemical.
Saimbhi and Randhawa (1977) found the pre-emergent application of linuron 0.5 kg/ha, alachlor 2.5 kg/ha, dichlomate 0.4 kg/ha and diuron 1.25 kg/ha useful for controlling weeds in bottle gourd, and Leela (1985) obtained better weed control with fluchloralin 2.0 kg a.i./ ha and alachlor 2.5 kg a.i./ha in bottle gourd cv. Pusa Summer Prolific Long.
ii. Training and Pruning:
Training bottle gourd vines over trellis is of great benefit since per unit area more number of plants can be adjusted, and it allows maximization of space by controlling vine growth and prevents the fruits from rot. It also helps in spreading of fruit on entire area, provides good leaves exposure and higher light interception, makes the spray easier, and maintains the vitality of the vine for a longer period. Training also allows the production of fruits with more uniform shape and colour and allows the gourds to grow straight and longer.
The most common trellis is a single overhead wire supported every 3.0-3.5 m with a strong post that are set at least 60 cm into the ground with at least 1.5 to 2.0 m above ground. Vines can be trained to the trellis by tying a twine in a loose loop around the base of the plant when the plants are 30-45 cm tall.
Tie the other end of twine to the overhead wire. Secure the vines to the wire until the tendrils develop to hold the vine in place. In Maharashtra, bottle gourd is trailed on bower system, which increases the yield 4-5 times than that obtained from untrained plants.
Vines of bottle gourd can be slightly pruned to increase the marketable yield per vine. The first flowers produced are generally male flowers. Appearance of female flowers is generally influenced by weather conditions.
It should not be a matter of concern if female flowers appear after the appearance of male flowers although the matter of concern is that the female: male flowers ratio should be high. Most fruits are produced on lateral branches since the female flowers are born on secondary branches so pruning the main stem to encourage lateral branch growth is a good idea.
The main stem is pinched at the end as and when length reaches 1 m. In field trials with this bottle gourd, the lowest numbers of female flowers, branches and fruits and ultimately the lowest yield per plant were recorded in treatments where branching on the main shoot was allowed from 9th to 15th node combined or not with pinching of primary branches after the 4th and 8th node or no pinching at all.
Topping the main shoot after the 6th or 12th node, irrespective of pinching or no pinching of the primary branches, also reduced yield and yield- contributing characters. The highest yield and number of fruits were recorded in unpruned control plants, and the various methods of pruning usually fail to exert favorable effects on fruit yield.
iii. Mulching:
In trials with bottle gourd, mulching with polyethylene increased the yield by 48-95% over the control, and good results were obtained with straw or sawdust mulches.
iv. Use of Plant Growth Regulators:
Environmental factors that affect the synthesis and level of endogenous auxins, gibberellins, ethylene, and abscissic acid determine the sex ratio in bottle gourd, and among the environmental factors, temperature is the most important ones since the low temperature alone during plant growth promotes the formation of female flowers and suppresses male flowers production.
On the contrary, the high temperature encourages the production of male flowers, which is due to the increase in endogenous level of gibberellins so the modification of sex to desired direction can be maintained by exogenous application of plant growth regulators once, twice, or even thrice at different intervals. High endogenous level of ethylene favors the female sex expression. The role of auxin is recognized in early evolution of ethylene.
Gibberellins play a key role in promoting male sex expression and antagonist to that of ethylene and abscissic acid. Singh and Choudhury (1989) obtained the maximum number of fruits in bottle gourd cv. Pusa Summer Prolific Long with foliar application of ethephon 50-100 ppm at 2 to 4 true leaf stage. The highest fruit length (61.6 cm) was obtained with NAA 100 ppm. Highest fruit girth (22.5 cm) and individual fruit weight (1.25 kg) were obtained with morphactin 50 ppm.
Highest number of fruits per plot for the early (7.8) and total yield (16.1), and fruit weight per plot for the early (8.83 kg) and total yields (18.26 kg) were obtained with the Ethrel 10 ppm treatment. The treatments GA3 25 ppm and morphactin 50 ppm resulted in early and total yields below those obtained in the control. Ethrel at 10 or 20 ppm was, therefore, considered the most effective treatment for increasing yield.
Spray of GA3 10 or 20 ppm at the 2- and 4-leaf stages caused the greatest elongation of the main axis; CCC (chlormequat) at 40 or 60 ppm and MH at 200 or 300 ppm suppressed apical growth, increased lateral shoot numbers, and early and total yields and improved the female: male ratio.
Arora et al. (1985) found the maleic hydrazide 50 ppm more effective in lowering down the male: female ratio, setting additional fruits and producing highest fruit yield as compared to the untreated control.
Application of maleic hydrazide (MH) 150 ppm significantly reduced the length of main axis, increased the number of shoots per plant, lowered the node at which the first female flower appeared, reduced the number of days to first female flower appearance, increased the number of female flowers, lowered the male: female sex ratio, increased fruit girth and weight and resulted in the highest yield (14 kg/plant and 335 q/ha) followed by ethephon (12.25 kg/plant and 293.7 q/ha) 50 ppm.
The spray of maleic hydrazide 50 ppm at 2- and 4-leaf stages significantly increased the number of branches, number of fruits per plant, fruit length and fruit weight significantly increased, and reduced the sex ratio and the number of days to the appearance of first female flower, and the higher fruit yield was recorded for MH-treated plants (319.2 q/ha) than for the control 267.3 quintal per hectare.
The growth, number of fruits per plant, yield, quality and the seed yield parameters increased with increasing concentration of Mixtalol (a mixture of biologically active, long-chain aliphatic alcohols) from 20 to 30 ml/10 litre of water applied at 45 days after sowing.
All the concentrations of soil-applied paclobutrazol (at 25, 50, 75, 100, 125, 150 and 175 mg/ litre) significantly decreased vine length, leaf size and fruit length, and increased side branches, fruit per plant, fruit diameter, total soluble solid and dry matter content. Paclobutrazol also caused an early appearance of female flowers on the nearest node (from the bottom). Paclobutrazol at 175 mg/litre was found superior among all the treatments.
Application of NAA 100 ppm has been recommended by Rahman and Karim (1997) to increase the yield of bottle gourd by increasing the appearance of female flowers. The scientists also recommended the use of TIBA (tri-iodo-benzoic acid) 75 ppm for lowering down the ratio of male: female flowers.
IBA at 500 ppm gave the highest number of roots per plant, root length, survival percentage and number of branches per plant and crop yield, and the shortest number of days required for rooting, flowering, and harvesting for bottle gourd cv. Arka Bahar.
Among the growth regulators (NAA, maleic hydrazide and cycocel each at 100 and 200 ppm, and a control) used, 200 ppm cycocel exhibited significantly lower values for the number of node and days to appearance of first male and female flowers in both years, recording pooled mean values of 7.50 nodes and 50.94 days for male flowers, and 11.03 nodes and 58.81 days for female flowers versus 9.94 nodes and 56.42 days for male flower and 13.81 nodes and 66.05 days for female flower in the control.
Cycocel at 200 ppm showed significantly lowest number of male and highest number of female flowers per plant in both the years, recording the mean value of 97.92 and 19.07, respectively, with a mean sex ratio of 5.24. Water regime x PGRs interaction was significant for node to appearance of first male flower and days to appearance of first female flower. The minimum values of both these attributes were recorded under irrigation at 25 mm CPE + 200 ppm cycocel.
11. Harvesting and Yielding of Bottle Gourd:
The fruits are picked from the vine by cutting the peduncle with sharp knife as and when the fruits attain the marketable size but still very soft and tender. The horticultural maturity, the right stage of harvesting, can be judged simply by observing persistence of pubescence on fruit surface. Skin of the fruit should not turn to white and seeds should not be hard. In markets, consumers prefer smaller fruits rather than the bigger ones, thus, the harvesting should be done according to the market preference.
Yield:
The yield of bottle gourd depends upon the cultivar and season. In general, bottle gourd gives higher yield in rainy season rather than the crop grown in spring-summer. On an average, a yield of 30-40 t/ha can be obtained following good package of practices during cultivation of crop.
Post-Harvest Management:
The prerequisite for better post-harvest management is to pick the fruits at right stage of maturity. For local market, the fruits are packed in mulberry/bamboo baskets or in plastic crates, and then, sent to the market, however, for distant markets, the fruits are packed in polyethylene film bags before packing them in small boxes. The fruits of long type varieties are always packed vertically not the horizontally to avoid bending of fruits due to their geotropic response.
Under cold and shady conditions, fruits of bottle gourd can be kept in good condition for a shorter period of 3- 5 days, however, in cold stores, the bottle gourd fruits can undoubtedly be stored bit longer but synthesis and accumulation of lignin in secondary cell walls make the fruits hard enough, and as a result, the fruits may not be cooked easily.
Post-harvest losses that include physical, mechanical, and physiological may occur due to improper methods adopted during harvesting, handling, transportation, distribution and due to unhygienic conditions too.
These losses can be minimized by handling the produce prudently and providing various post-harvest treatments such as removal of field heat with different ways, and then, packing after giving treatment with safer fungicides such as Benomyl that can help extend the storage life by discouraging the incidence of microorganisms. The waxing of fruits can also help control the post-harvest losses occurring due to dehydration.
12. Cultivated Varieties of Bottle Gourd:
Large variation exists in both size and shape of bottle gourd fruits. Its size ranges from 10 cm to sometimes nearly a meter long, and shape varies from flattened round to long. The round fruited varieties are suitable for cultivation in spring-summer and the long types in rainy season.
The varieties developed by different Institutes and State Agricultural Universities are being discussed below:
A. Long Cylindrical Fruited Varieties:
1. Pusa Summer Prolific Long:
A long type variety developed by Indian Agricultural Research Institute, New Delhi through a selection from local germplasm is suitable for growing in spring-summer season, although it can be grown in rainy season. Fruits are 40-50 cm long with 20-25 cm girth. On an average, a vine bears 10-15 fruits, which are pale green in colour. Its average yield is 150 q/ha.
2. Pusa Meghdoot:
An early bearing F1 hybrid developed at Indian Agricultural Research Institute, New Delhi in 1971 through a selection from the cross Pusa Summer Prolific Long x Selection-2 is suitable for growing in spring-summer season. Fruits are light green in color, long, and attractive. Its yield is higher than Pusa Summer Prolific Long.
3. Pusa Manjari:
A F1 hybrid developed at Indian Agricultural Research Institute, New Delhi in 1971 through a selection from the cross Pusa Summer Prolific Round x Selection-11 is early bearer. Fruits are round and light green in color. It yields double than Pusa Summer Prolific Round.
4. Pusa Naveen:
An early and high yielding long fruited variety developed at Indian Agricultural Research Institute, New Delhi is suitable for cultivation in spring-summer and Kharif [winter] season. The fruits are straight, cylindrical and 30-35 cm in length without a neck and suitable for packing and transportation to distant markets. Its average fruit weight is 850 g and yield is 300 q/ha.
5. Pusa Hybrid-3:
A variety developed at Indian Agricultural Research Institute, New Delhi for commercial cultivation in northern plains bears fruits that are suitable for packing in cardboard boxes for distant markets. It can be successfully grown in both spring-summer and rainy season. Its yield, which is 45% higher than Pusa Naveen, is 425 quintal per hectare.
6. Punjab Long:
A cultivar developed at Punjab Agricultural University, Ludhiana bears long, cylindrical, light green and shining fruits that can be packed for long distance markets. Its average yield is 450 quintal per hectare.
7. Arka Bahar:
A long type variety developed at Indian Institute of Horticultural Research, Bangalore through a selection from local cultivar of Karnataka bears straight without crookneck and medium size fruits, weighing 1 kg per fruit. It yields 400 quintal per hectare.
8. Pant Sankar Lauki-1:
A hybrid variety developed at G.B. Pant University of Agriculture and Technology, Pantnagar and released by CVRC in 1999 is prolific bearer with medium long fruits. Its average yield is 500 quintal per hectare.
9. Kalyanpur Long Green:
A variety developed at Vegetable Research Station Kalyanpur, Kanpur bears long fruits with tapering end. It yields 300 quintal per hectare.
10. Samrat:
A variety developed at Mahatma Phule Krishi Vidyapeeth, Rahuri in 1992 through a selection from local germplasm collected from Dahanu district of Maharashtra bears 30-40 cm long and cylindrical fruits that are most suitable for packing and transportation to long distance markets. Its average yield is 400 quintal per hectare in duration of 180-200 days.
11. Azad Nutan:
An early fruiting variety developed at Kalyanpur through a single plant selection from indigenous material can be cultivated in both spring-summer and rainy season. Fruits are shiny light green with soft pubescence, long, and crooked neck free, weighing 1.5 kg.
B. Round Fruited Varieties:
1. Pusa Summer Prolific Round:
A high yielding cultivar developed at Indian Agricultural Research Institute, New Delhi through selection from local germplasm bears round fruits with average girth of 15-18 cm.
2. Punjab Round:
A cultivar developed at Punjab Agricultural University, Ludhiana bears flat-round, tender and shining fruits. Its average yield is 375 quintal per hectare.
3. Punjab Komal:
An early maturing medium sized oblong-fruited cultivar tolerant to cucumber mosaic virus developed at Punjab Agricultural University, Ludhiana from a cross between LC11 (round) and LC5 (oblong) is consistently superior to Punjab Round and Pusa Summer Prolific Round over a 5-year period (51 vs. 39.3 and 38.5 t/ha) and is suitable for growing in both spring-summer and rainy season.
The fruits are light green in colour with pubescence. It bears on an average 10-12 fruits per vine. When compared with other two varieties, it produces more and larger fruits per plant (on average 12.66 fruits per plant, average weight 623.21 g) and has the shortest maturing time. It yields 500 quintal per hectare.
4. Pusa Sandesh:
A variety developed at Indian Agricultural Research Institute, New Delhi bears green, round, deep-oblate and medium-size fruits weighing on an average 600 g each. It is recommended for cultivation in both spring-summer and rainy season in the northern plains. Its average yield is 290-320 q/ha.