How to improve the fruit setting rate of plums

1 regulating the tree potential

For trees that are too strong, it is necessary to wipe buds and prune erect branches in time, and open the branch angle in time; it is also possible to apply 15% paclobutrazol 3g 5g in autumn or spring, or spray 150m 200 times paclobutrazol or PBO after falling flowers. For trees that are too weak, base fertilizer should be applied after fruit harvest, and fertilizer should be topdressing and spraying in time during the growing period.

2 pollination

2.1 when setting up a garden with pollination trees, the pollination trees should not be less than 30%, especially for those varieties with low self-pollination rate or low pollen quantity.

2.2 release 1 box of honeybees per 0.1~0.2hm2 orchard or 200 horned frontal wall bees per 666m2 before blooming.

Or gently roll between the flowers of the main varieties and the pollinated varieties with a feather duster or towel stick, or mix the collected pollen with talcum powder at 1:1, put them into a cloth bag and shake and pollinate on the trees of the main varieties at full flowering; the flower branches can also be inserted into a water bottle and hung on the trees of the main varieties.

In addition, spraying 300 times 500 times borax and 100 times sugar or brown sugar at flowering stage can increase the fruit setting rate.

(3) to prevent frost injury during flowering.

3.1 to build a windbreak forest on the north and west side of the orchard, the windbreak forest had better adopt the mixed mode of Arbor and irrigation, so that a dense windbreak wall can be formed below 1m to reduce freezing damage.

3.2 pay attention to the site selection of the low-lying land is easy to accumulate cold air, which will aggravate the freezing damage. Therefore, try not to build a garden in low-lying land.

3.3.When the fumigation is nearing flowering, pay attention to listen to (watch) the weather forecast, forecast the occurrence of frost injury at night, prepare firewood or smoke agent ahead of time in the orchard, put a pile of firewood or smoke agent every 20m, and start smoking when the temperature drops below 0 ℃. Pay attention to the smoke pile should be 10m away from the tree, and there should be a special guard to prevent open fire from burning the trees. Smoking is more effective in preventing advection frost.

3.4 sprinkler irrigation facilities are available for conditional irrigation to intermittently spray trees on frost nights. Or irrigation under the tree has a better effect on reducing radiation frost.

One is in the flower bud expansion stage of the plum tree, spraying 500~2000mg/L anthocyanin, or 1%-2% lime water on the tree can delay flowering for 3-5 days. Second, the top of the spring is irrigated in February, and after the surface is frozen, the wheat straw is covered under the tree, which can also delay flowering for 3-5 days. In addition, the degree of pruning is aggravated in winter, combined with coring in summer, secondary shoots are cultivated for 2 or 3 times to form fruit branches, which can delay flower bud germination and avoid frost.

3.6 close planting can increase the frost resistance of the population. Due to the sinking of cold air, flower buds below 1m are easy to suffer frost damage, so the tree trunk left a little higher can reduce the freezing damage of lower cold air to flower buds.

3.7 the varieties with late flowering or frost resistance were selected.

(4) Control Li Shifeng.

At the end of blooming, the damage can be basically controlled by meticulous spraying of 1500 times of Lexben or 1500-2000 times of permethrin on the crown, and once more after one week. Li Shifeng produced one generation a year and overwintered in the soil under the tree. at the end of blooming, he sprayed 500 times Lesbon or isocarbophos powder on the ground, and then shallow hoe. Pick up the insects and fruits that fall to the ground and transport them out of the orchard for destruction, which can destroy most of the Li Shi bees.