Measures for fruit protection of papaya trees planted with papaya

The purpose of fruit preservation is to increase the fruit setting rate and reduce the drop of flowers and fruits. There are three main reasons for the flower and fruit drop of papaya: first, the tree is not strong, the growth is prosperous and weak, the tree body nutrition is insufficient, which leads to serious flower and fruit drop; the second is poor pollination and fertilization, and the lack of hormone transfer nutrition in the ovary leads to flower and fruit drop; third, too much fruit, too much nutrition consumption, can not meet the demand for fruit drop. In view of these situations, specific measures need to be taken to protect the fruit.

1. Reasonable pruning to improve fruit setting rate.

On the basis of winter pruning, pre-flowering re-pruning can further adjust the amount of flower buds and maintain a suitable ratio of vegetative branches to fruiting branches. Early cutting of redundant flower buds and retraction and renewal of weak branches can save concentrated nutrition and improve fruit setting rate.

The fruit setting rate can be increased by coring the vegetative shoots with abundant growth, removing some exuberant stem tip growth points, reducing the synthesis and nutrient consumption of auxin and gibberellin, alleviating the competition of nutrients needed for vegetative growth and young fruit development.

two。 Spray fertilizer out of the root.

Spraying branch nitrogen with 0.5%-1% urea before budding of papaya in early spring can increase storage nutrition, increase early leaf area, improve early photosynthetic efficiency and promote fruit setting.

Under the premise of strong tree growth and good supply of main mineral nutrients, spraying trace element fertilizer plays an obvious role in promoting fruit setting, especially in the park where some trace elements are deficient. Spraying 0.3% borax solution and 0.3% urea solution 2 times before and after flowering can promote pollen germination, pollen tube elongation, accelerate pollination and fertilization process, and significantly increase fruit setting rate.

3. Configure pollination trees and auxiliary pollination at flowering stage.

Papaya white flower pollination seed setting rate is high, about 50%, cross-pollination seed setting rate is 87%, the phenomenon of direct pollen is obvious, production needs to be equipped with appropriate pollination trees. When equipped with pollinated varieties with large fruit and high quality, the fruit is also large.

Artificial pollination is needed because of bad weather during flowering period, insufficient number of pollination trees or improper collocation. Select high-quality pollination varieties, pick budding bell flowers from robust trees, and take out anthers. When pollination, when the number is small, use a brush to dip pollen on the blooming style; when the quantity is large, you can use 10 kg of water, 0.5 kg of sugar, 30 g of urea, 10 g of borax, 20 g of pollen, 500 times the liquid of pollen, and spray it with a back sprayer.

4. Thinning flowers and fruits.

Timely dredging excessive flowers and fruits of papaya trees and achieving reasonable load is an important technical measure to strive for high yield, stable yield and high quality, and to prevent and overcome annual fruit. General producers are thinning flower buds during pruning, bud thinning before flowering, flower thinning during flowering, and fruit thinning within a week to a month after flowering.

Artificial thinning of flowers should first sparse inferior flowers with weak growth and small flowers, and first sparse clusters of flowers and dense branches of inflorescences. First thinning the tree, then under the tree; first thinning the crown, then the periphery. On a main branch, the base and tip are thinned properly, and more are left in the middle. Branch group flowers, should leave the front, sparse the back of the head, in case of retraction. Within an inflorescence, sparsely fringed, leaving a flower in the center.

Sparse fruit first sparse odd-shaped small fruit, and then according to the amount of fruit left, determine to leave a single fruit or double fruit. Leave fruit spacing, large fruit about 20 cm, small fruit about 15 cm.