The most important thing for the high yield of pear trees lies in the flower tube.

1. Fertilizer and water management if insufficient nutrients affect fruit setting and young fruit expansion during flowering, urea is applied 20 days before flower bud germination, and the amount of fertilizer is generally determined according to tree age, tree potential, yield and nutritional status in the first half of the year. Spraying 0.20% Mel 0.50% boric acid solution at flowering stage and after anthesis can increase the fruit setting rate.

2. The main functions of flower thinning: one is to reduce the nutrient consumption during flowering, increase the fruit setting rate, and overcome the size of the year; the other is to ensure the right amount of fruit, large and neat fruit, less residual fruit. Generally speaking, flower bud thinning is better than flower thinning, flower thinning is better than fruit thinning, and early thinning is better than late thinning. Decide which method to take according to the number of flowers, tree strength, weather, pollination and fruit setting in the current year. For example, if the number of flowers is large, the trees are strong, the weather is good, and the workload is heavy, it can be early thinning of buds, flowers, and final fruit. On the contrary, the fruit can be fixed only once, and fruit thinning should be completed within 4 weeks after falling flowers.

3. Auxiliary pollination

3.1 necessity of pollination most pear varieties do not bear fruit by themselves. When there are strong wind, dry and hot wind and sand, overcast and rain, low temperature during flowering, frost and other adverse weather, media insect activities are affected, or flower organs are damaged, which will significantly affect pollination and reduce fruit setting rate. Because honeybee pollination is carried out forward, the probability of serial pollination is only 27% MUE 30%, which is particularly disadvantageous to closely planted pear orchards where pollination trees are planted in rows. Moreover, the pollen cells of pear trees began to form in early spring from February to March. In the pear orchard with poor management or big year last autumn, due to the lack of storage nutrients, the spring pollen was stunted or aborted. Even if there are pollinated varieties, there will be poor natural pollination. If artificial pollination is adopted, the fruit setting rate can be increased by 5 times, and the yield can be more than 1.5 times.

3.2 pollination method (1) pollination by bees: put a box of bees in every 10 mu of pear orchards and put them in the orchard 2 Murray 3 days before flowering. Pear orchards without pollination trees can put the pre-collected pollen at the door of the beehive to make bees go in and out covered with the whole body to impart pollen. (2) Feather duster rolling: in a pear orchard with pollination trees, in full bloom, a feather duster is used to roll over the pollination tree flowers and pick up pollen, then transfer to the main varieties and gently roll them back and forth for 1 Mel twice. (3) artificial tapping: manual tapping can be used when there is no pollination tree or when the pollination tree is young, the number of flowers is insufficient, or the flowering weather is bad. The dispenser can be tightly rolled into paper and twisted with a newspaper, or a handle can be inserted with a bicycle valve core. You can order more than a dozen flowers each time you touch the powder. (4) pollination: pear orchards or years that require large-scale pollination can be pollinated by a small dusting machine or sprinkler. When spraying powder, generally 1 part of pollen is mixed with 20 parts of dry starch, and 30 parts of dry starch are used immediately. The formula of liquid spray is that 50 grams of pollen with anther shell is put into 25 kilograms of water to form a suspension, and the anther shell can be filtered out. Or 15 grams of pure pollen, add 25 kg of water, 0.10% boric acid and 10% sucrose, mix and spray. It must be finished within 2 hours.

3.3 Pollen collection methods: varieties with strong affinity and large amount of pollen were selected as pollination varieties. Collect mature anthers that are about to crack or just crack and spread them thinly on smooth paper, dry them under astigmatism or dry them in 23 ℃ 25 min room temperature to make the anthers crack. When collecting a large amount of pollen, it is advisable to collect flowers and collect pollen in the southern area where the flowering period is early one week in advance. The collected pollen is kept under the condition of low temperature and drying.

4. the period of pear flower bud germination is the stinging period of adults such as pear planthopper, pear aphid, pear net bug, mountain plant red spider, pear heart borer, pear star caterpillar and so on. Beetles, pear wasps and other underground pests also began to sting. Pear scab, brown spot and other pathogens also began to spread before flowering. Insecticides include 1500 times of omethoate EC, 1000 times of isocarbophos EC and 3000 times of fenvalerate EC; fungicides include: 50% carbendazim wettable powder 600 times 800 times, 70% methyl topiramate 800 times, 70% mancozeb 400 times 500 times. Pesticides and fungicides can be mixed.