Today I wish to stand in the gap between yield forecasters and the real results for all fruiting vegetables. For quite some time seed breeders have come up with high yielding vegetable varieties but the actual yield has been a challenge to many farmers. The seed breeders have the potential to take care of the crops in terms nutrition, pest and disease management so their yield target does not match/rhyme with the yield obtained by farmers, and notably the deviation is quite substantial. For vegetable yield forecast one counts the number of flowers to estimate the number of fruits expected per plant, then multiply the number of flowers by the number of plants in a given piece of land.
Effect of Blossom drop in crop Yield
Assume one tomato produce ten flowers and the number of plants equals two hundred, using the formulae yield=number of flowers produced per plant*number of plants, i.e. 10*200=2,000 fruits.This method has been compromised by conditions such as blossom drop which has hit many farmers who merely fail to understand why their vegetable fruit yield remains low despite of good crop performance in terms of growth and development.
Blossom drop is the loss of flowers usually preceded by yellowing of the pedicel. We understand that the tomato flower has both male and female parts within the same flower, the yellow stamens wrap around the greenish pistil at the center of the flower. Under desirable conditions, the pollen from the stamens transfer to the sticky stigma or tip of the pistil. This transfer requires a jarring wind, a flick of finger or insect. Am made to understand that, tomato blossoms are self-fertile, and a certain amount of self-pollination of tomato flowers do occur but pollen does not move well by itself from anther to the stigma as evidenced by the really poor pollination in green house tomatoes where the pollination is totally unaided.
But shaking by the wind or mechanical means can cause the release of the pollen, it drops downward through the stamen tube to the stigma. The best possible motion to release this pollen is from the bee that “solinates”, vibration of the insect wing muscle without flight that causes the whole flower to vibrate, this causes the release of a cloud of pollen on to the insect body and onto the stigma. Without pollination which stimulates fruit set, the flower wither and dies off.
Crops Mostly Affected
Blossom drop is a condition observed in tomatoes, peppers, snap beans and many other fruiting vegetables where the plant blossoms but fails to set fruit, the blossom dies and drop off. Tomatoes lose their blossom due to various reasons usually linked to some kind of stressful conditions, either nutritional, environmental or combination of the two.
NBAnything that intercede pollination and fertilization process may result to flower abortion.
Apart from lack of pollination, other causes of blossom drop are mostly related to either temperature or stress, which makes it very hard for gardeners to control. These causes include Nitrogen (Too Much or Too Little), Humidity (Too High or Low), Lack of water, stress from insect damage or disease, heavy Fruit Set.
Control:I recommend farmers to employ Good Agricultural Practices (GAP) and also grow varieties adapted to their specific agroecological zones to avoid predisposing factors brought about by the climate.