Fruit growers pay attention to the two flowering of pear trees in autumn.

What is the flowering of pear trees? No kidding! Hearing this news, I believe many growers who have not experienced this experience must not believe it! Let's talk about the two flowering of pear trees.
First of all, the two flowering of pear trees is indeed there. The second flowering of pear trees means that pear trees bloom twice in a year, which can be seen from early October. The serious flowering rate of pear trees can reach about 50%. The second flowering of pear trees not only consumes a lot of nutrients, seriously weakens the tree vigor, but also sprouts and blooms ahead of time, seriously affecting the yield and quality of the next year. At the same time, it also causes a large number of autumn shoots and leaves, affecting the safe overwintering of the tree.
Since pear trees bloom two times and hurt the pear trees so much, how should we prevent them? To prevent the two flowering of pear trees in autumn, we must first find out the reason.
The reasons for the two flowering of pear trees can be roughly divided into the following:
1, the physiological characteristics of pear bud differentiation. The flower bud differentiation of pear trees begins earlier, usually in early May after flowering, young fruits begin to accelerate growth, flower bud differentiation begins; in mid-late June when young fruits rapidly expand, flower buds also enter a large number of differentiation period; generally in mid-July calyx began to form, most of the early August stamens began to form, in mid-August stamens began to form, in mid-August Pistils begin to form in late June to early September. When the fruit was harvested, most of the flower buds had been formed, making full preparations for flowering. In this way, if the fruiting pear trees, whether in big or small years, encounter adverse environment after harvest, resulting in a large number of fallen leaves, forcing them into dormancy, thus completing the necessary physiological dormancy stage before flowering. When the weather condition is the same as that of spring in October, soil nutrients and water are better, and carbohydrates are formed more, flower buds are easy to germinate and produce secondary flowers.
2. Reasons for pear varieties. Different pear varieties have different adaptability to the environment. According to the observation records in recent years, the autumn blooming of the new century, Fengshui pear and other varieties is the most serious, followed by Hangqing, Cuiguan, Huanghua pear is lighter.
3, pests and diseases are serious, leading to premature defoliation. Such as pear scab, black spot, rust, rot disease, pear gall mite, pear lice, red spider, pear net bug and other damage can cause early defoliation of pear trees, is the main reason for the second flowering of pear trees. Especially the pear louse, the pear net bug and the pear gall mite, all take the leaf juice by the puncture suction mouthpiece, the leaf withers and falls off gradually after being injured, these insect pests are the most serious damage from July to early September, if the high temperature and the persistent drought weather occurs in this period, it is extremely easy to make the pear tree enter the dormancy period.
4, extensive cultivation and management. Improper shaping and pruning, disordered crown structure, erect branches, irregular shooting, poor canopy permeability, resulting in serious pests and diseases, less fertilization, only chemical fertilizer, little or no organic fertilizer, no fruit picking period, resulting in weakening of tree vigor, early defoliation, and serious secondary flowering phenomenon.
5, improper picking. In high-yielding years, excessive fruit hanging and neglect of proper fruit thinning affect the normal growth of branches and shoots; fruit picking destroys the balance of water metabolism in the tree after all one-time harvesting, coupled with more wounds, serious water loss, will cause leaf wilting, accelerate the formation of petiole layer, thus early deciduous leaf formation of secondary flowering.
Knowing the reason for the two flowering of pear trees, we can prescribe the right medicine.
1. Physiological characteristics of flower bud differentiation of pear trees: applying basal fertilizer after fruit harvesting, cutting off part of the root system of pear trees, temporarily breaking the balance between the aboveground and underground parts of the tree, thus inhibiting flower bud germination. For slight orchards with secondary flowers, buds or fruits can be removed, and some available nitrogen fertilizers can be applied to restrain the growth of flower buds. For the pear trees with serious secondary blossom, high flower-grafting technique can be used, that is, cutting the flower buds which will be thinned in winter from the robust pear trees to make up for these high flower-grafting buds and strengthening management to reduce yield losses.
2, for pear varieties: choose strong resistant varieties. In pear orchards with serious secondary blooming, the varieties with lighter secondary blooming such as Huanghua pear and Cuiguan can be replaced by high grafting, and cultivation management should be strengthened to prevent secondary blooming.
3. For pear diseases and insect pests: after normal defoliation to the next spring sprouting, the number of pests and diseases in the garden can be effectively reduced by cutting off the branches of pests and diseases, sweeping the defoliation and burning or burying deeply, and spraying the second lithium sulfur mixture to clear the garden. In spring and summer, pear trees were able to control leaf diseases in time. The main control period of these diseases was 4-7 months. It can be used alternately with fungicides such as 10% Shigao 1500-2000 times liquid, 25% Fanruling 2000-3000 times liquid, 50% isomycocarbamide 500-1000 times liquid, 30% Aimiao 3000 times liquid and 75% chlorothalonil 500-800 times liquid. The pests that cause early defoliation of pear trees, such as Pyracea reticulata, Pyracarpa pyrifolia and Pyracarpa xylophilus, should be controlled in time in the middle and late May. The key period of controlling the pear net bug is in the middle and late May. During this period, the orchards should be inspected regularly. When a small number of insect pests are found on the leaves, the pesticides should be sprayed immediately, and then sprayed once a week later. With 40% dimethoate emulsion 1000 times liquid or 50% dichlorvos 1200 times liquid, 2.5% HCFC 2500 times liquid and 10% bifenthrin 2500 times liquid can effectively control. Pear lice control two times before and after flowering. Use 1.8% avermectin EC 4000-6000 times liquid, 25% pyrazone 2500 times liquid, 25% Thiazone 1000-1500 liquid spray. Pear leaf mites. There were first peaks in 5-6 months, the second peak in late July to August. It can be used for 5% times 2000-3000 times of 20% or three chloracarb 800-1000 times.

Previous：Wish you eleven happy National Day!         Next：Factors affecting pollination quality of apple tree