Generally, germination of bittergourd seeds in the field is less and also delayed. This results in non uniformity in plant growth and fruit maturation. This can be over come by using pre germinated seeds.
For pre germination, the bittergourd seeds should be soaked in water for 24 hours. Then soaked seeds is to be mixed with double the volume of moist sand and seed should be fully covered by the sand and keep it for three days. During this period moisture of sand should be maintained. After that, the seeds with radicle emergence are to be collected and used for sowing.
Spreading of bitter gourd vines in the trellis
Seeds of 1.8 kg pre germinated seeds required for an acre may be sown in a pit with three seeds at equal distance. If we are using pre-germinated seeds, sow only three seeds per pit.
After sowing pits should be irrigated with water. Care must be taken that the soil should not be eroded and seed should not be exposed. After the seedling emergence, field should be irrigated once in a week.
Main field maintenance
Ten days after the germination, retain one vigorous seedling per pit and remove two seedlings. It will facilitate for better growth of seedling without any competition between them. 20-25 days after sowing, each plant has to be provided with stacking for trailing the vines over the pandal. Trailing operation has to be carried out daily until the fruiting stage.
Maintaining the field free of weed is more important for the crop growth. In bittergourd, one or two manual weeding is necessary before the flowering stage.
Growth regulator spray
Generally in cucurbitaceous vegetables the male and female flowers are born separately. The number of female flowers decides the fruit yield. Hence, for bittergourd, spraying of ethrel at 200 ppm for four times starting from 15 days after sowing and followed by weekly intervals (i.e. 2.0 ml of ethrel in 10 lit of water). This facilitates for higher fruit yield.
Seed crop is entirely different from vegetable crop. Hence, fertilizer is applied as two or three split doses. Two split dose of urea as 22 g/pit at flowering stage and another 18 g urea plus 5 g potash / pit each at 20 and 40 and quality seed yield.
Maintaining seed quality by rouging
One of the most important aspects of seed production is thorough rouging. Rogue is defined as of those plants that deviate from the characters described for the variety. Such rogues if left in the field they tend to reduce the genetic purity of the seed crop and thus reduce purchase value of resultant seed. Roguing is defined as the operation of removing rogues. In practice, all virus infected plants are to be removed.
When to do roguing ?
Roguing is more effective if done prior to flowering, since upon flowering there is very high possibility of cross pollination. Roguing is also attempted during vegetative phase, fruit formation stage and prior to harvest.
Rogueing during vegetative phase
During vegetative phase, during first 30-35 days, rouging is attempted based on plant characters like height of plant, leaf shape, size, surface of leaf.. Plants showing heavy branching and spreading nature are removed. Plants showing variation in stem or leaf base color are also removed. Those plants showing symptoms of yellow mosaic are also removed.
Rogueing during fruit formation phase
At this phase, the rogues are removed based on fruit characteristics like length of fruit, size, shape and color.
Rogueing during fruit harvest phase
Rogueing is done prior to harvest based on fruit color and pests and diseases infection. While harvesting, the workers can be taught to separate infected fruit from good ones and forward only the uninfected fruits for seed extraction.
In bitter gourd the harvest is not as that done is field crops as once over harvest. The harvests will be done in different pickings in biitergourd. Here the first and last one or two harvests may be taken for vegetable. The fruits harvested in between these harvests are used for seed extraction.
supplier :KN Seeds Hyderabad