Reasons for low fruit set rate in lychee and solutions
Lychee is a fruit deeply loved by consumers and one of the crops chosen by many growers, but during cultivation, the phenomenon of low lychee fruit set rate can occur, seriously affecting lychee yield. So is there any way to improve the fruit set rate of lychee? Let's take a look during the break.
1. Bee release or artificial pollination
Lychee is a crop with separate male and female flowers and cannot pollinate itself; it needs pollination through a pollination medium to set fruit. When the weather is good, releasing bees or adopting artificial pollination can improve the fruit set rate. Generally, 0.5-1 hive is released per mu, and the bees are brought into the orchard 3-5 days before flowering. Artificial pollination can increase the reasons for female flowers, achieve the effects of cooling and increasing application, and prolong effective pollination. Generally, on a clear morning, collect the opened male flower panicles, filter them with clean water, then add borax and fruit-setting hormone. When pollinating, dilute with water and spray on the female flowers.
2. Shake branches and spray water
When encountering rainy weather during full bloom, shake the branches promptly after the rain clears to shake off the rainwater on the flower panicles and accelerate flower drying and pollen dispersal, so as to avoid flower rotting. When female flowers are in full bloom, if it is hot and dry, the sugar liquid on the stigma becomes viscous, which is not conducive to nectar collection and pollination. Therefore, at this time, irrigation and water spraying can be done to increase humidity and reduce the viscosity of the sugar liquid, so as to facilitate pollination.
3. Prevent diseases
When the third batch of male flowers opens, if there is hot and rainy weather, it is very easy to infect Yimiba, which will cause the male flowers to lose vitality and be unable to pollinate. Therefore, measures should be taken promptly for prevention. One week before flowering, spray a low-concentration carbendazim agent or thiophanate-methyl for prevention. After rain, shake the branches promptly to speed up the drying of the flower panicles and reduce the probability of disease occurrence. When the disease is severe, carbendazim and powdered filler can be mixed evenly at a ratio of 1:9, wrapped in a gauze bag and tied to the end of a bamboo pole, then shake and scatter it on the affected parts, which can control the spread of the disease. In addition, flower thinning can also control the disease.
4. Protect flowers and fruits
Ten days after female flowers are in full bloom or when young fruits set, adopt root-side fertilization to protect flowers and fruits. You can use 50 grams of borax, 100 grams of urea, and 50 grams of potassium dihydrogen phosphate, add 50 kg of water, and spray on leaves. When the fruit grains begin to grow, use 100 grams of urea, 50 grams of potassium dihydrogen phosphate, and 1-1.5 grams of fruit-setting hormone diluted in 50 kg of water and spray, which can produce an excellent flower and fruit protection technique and improve the fruit set rate.
The above is an introduction to what to do when the lychee fruit set rate is low. I hope it can help you. To learn more related knowledge, please follow us.