First, nutrient requirements and proportion:
Pear nutrient management should adhere to the principle of organic fertilizer, in combination with the application of a variety of chemical fertilizers, pear orchard soil orchard soil organic content should be above 1.5%, which is the basis for strong trees, high yield, and high quality. However, at present, the soil organic matter in pear orchards in China is generally between 0.6% and 0.8%. Therefore, the use of organic fertilizer should be emphasized. For the application of chemical fertilizers, attention should be paid to multiple compounding. At present, there is a tendency for N fertilizer to be applied to the production of pears, and N, P, and K light Ca, Mg, and trace elements should be emphasized. Similar to apples, the determination of pear fertilization is also based on yield and adjusted according to tree vigor, tree age, site conditions, and diagnostic results.
1. According to the yield: According to the yield of 37,500 kilograms of pear fruit per hectare, based on the nutrient content of pear branch, stem, root, leaf, and fruit, the required nutrient amount for each 100 kilograms of pear fruit is calculated.
2, according to age: In order to facilitate the calculation, only a few commonly used fertilizers, using other fertilizers can be based on the pure nutrient conversion, in the production of promoting the use of compound fertilizer or special fertilizer.
3. According to the soil fertility level: The annual fertilization amount per hectare (495 plants per hectare) under medium and moderate fertility conditions is 180 kg of pure nitrogen, 120 kg of phosphorus (P2O5), and 180 kg of potassium (K2O).
4, according to tree potential: This part can refer to Apple.
Second, the proportion of nitrogen, phosphorus and potassium: According to the sand culture test, the ratio of nitrogen and potassium is 1:1, and the phosphorus requirement is about half of nitrogen. Young trees absorb more nitrogen and have slightly less potassium. Phosphorus is about one-fifth that of nitrogen. Japanese studies have shown that in the nutrient content absorbed by pears, soil provides nutrients, nitrogen accounts for about 1/3 of total absorption, and phosphorus and potassium account for 1/2, respectively. The utilization rates of N, P2O5, and K2O for pears were 50%, 30%, and 80%, respectively.
Third, the fertilization period: China's pear orchard fertilization has the base fertilizer, top dressing points, the specific application is as follows:
1, base fertilizer. The main organic fertilizer, with the right amount of nitrogen, phosphorus, potassium fertilizer. After harvesting fruit in autumn, it is combined with deep plowing and deep plowing before defoliation.
2, top dressing. The top dressing of pear in our country is usually selected from 1 to 3 times in the following periods:
Fertilizing before flowering: The germination, flowering, leafing and pumping of early spring buds consume large amounts of nutrients. When the new shoots begin to grow, it is the time when the storage nutrients are about to be consumed. At this time, a large amount of nitrogen is needed. If nitrogen deficiency at this time will affect flowering and fertilization, resulting in fruit drop, making the leaves small and thin, light in color. Therefore, there are few photosynthetic products, few fruit set, and small fruit. If the tree vigor is strong and there are too many flower buds, in order to control the amount of flower and fruit, you may not apply fertilizer before flowering and change fertilizer after flowering.
After flowering, the top dressing is applied before the flowering period or after the flowering period. The purpose is to promote the growth of the branches and leaves, to create the conditions for flower bud differentiation and fruit enlargement, and to overcome the third fruit drop due to lack of nutrients. However, the amount of fertilizer should not be too much, the fertilization period should not be too late, so as not to cause new shoots excessive, affect the increase of flower buds and fruits.
Fruit enlargement fertilizer: It is usually applied when the growth of spring shoots is slow until the growth of spring shoots is stopped. In addition to nitrogen fertilizers, phosphorus and potash fertilizers, especially potassium fertilizers, are also used. After the spring shoots stop growing, nutrients are mainly used for vigorous root growth, increase leaf color, and increase photosynthesis intensity, thereby promoting flower bud differentiation and fruit enlargement. In production, the amount of post-harvest fertilizer is often increased, and the fruit enlargement fertilizer is postponed until one month before fruit harvest. This has a good effect on the growth and development of flower buds and the later increase of fruit.
Post-harvest fertilizer: This time, the fertilizer was applied in the middle or late September after it was deciduous after fruit picking. The main role is to improve the function and longevity of the leaves, promote photosynthesis, enrich the shoots and storage of nutrients, and lay the foundation for the next year's high yield. For nitrogen, phosphorus, and potassium, the proportion of nitrogen fertilizer is more important. This top dressing can also be applied together with organic fertilizer in the form of base fertilizer.
Pear nutrient management should adhere to the principle of organic fertilizer, in combination with the application of a variety of chemical fertilizers, pear orchard soil orchard soil organic content should be above 1.5%, which is the basis for strong trees, high yield, and high quality. However, at present, the soil organic matter in pear orchards in China is generally between 0.6% and 0.8%. Therefore, the use of organic fertilizer should be emphasized. For the application of chemical fertilizers, attention should be paid to multiple compounding. At present, there is a tendency for N fertilizer to be applied to the production of pears, and N, P, and K light Ca, Mg, and trace elements should be emphasized. Similar to apples, the determination of pear fertilization is also based on yield and adjusted according to tree vigor, tree age, site conditions, and diagnostic results.
1. According to the yield: According to the yield of 37,500 kilograms of pear fruit per hectare, based on the nutrient content of pear branch, stem, root, leaf, and fruit, the required nutrient amount for each 100 kilograms of pear fruit is calculated.
2, according to age: In order to facilitate the calculation, only a few commonly used fertilizers, using other fertilizers can be based on the pure nutrient conversion, in the production of promoting the use of compound fertilizer or special fertilizer.
3. According to the soil fertility level: The annual fertilization amount per hectare (495 plants per hectare) under medium and moderate fertility conditions is 180 kg of pure nitrogen, 120 kg of phosphorus (P2O5), and 180 kg of potassium (K2O).
4, according to tree potential: This part can refer to Apple.
Second, the proportion of nitrogen, phosphorus and potassium: According to the sand culture test, the ratio of nitrogen and potassium is 1:1, and the phosphorus requirement is about half of nitrogen. Young trees absorb more nitrogen and have slightly less potassium. Phosphorus is about one-fifth that of nitrogen. Japanese studies have shown that in the nutrient content absorbed by pears, soil provides nutrients, nitrogen accounts for about 1/3 of total absorption, and phosphorus and potassium account for 1/2, respectively. The utilization rates of N, P2O5, and K2O for pears were 50%, 30%, and 80%, respectively.
Third, the fertilization period: China's pear orchard fertilization has the base fertilizer, top dressing points, the specific application is as follows:
1, base fertilizer. The main organic fertilizer, with the right amount of nitrogen, phosphorus, potassium fertilizer. After harvesting fruit in autumn, it is combined with deep plowing and deep plowing before defoliation.
2, top dressing. The top dressing of pear in our country is usually selected from 1 to 3 times in the following periods:
Fertilizing before flowering: The germination, flowering, leafing and pumping of early spring buds consume large amounts of nutrients. When the new shoots begin to grow, it is the time when the storage nutrients are about to be consumed. At this time, a large amount of nitrogen is needed. If nitrogen deficiency at this time will affect flowering and fertilization, resulting in fruit drop, making the leaves small and thin, light in color. Therefore, there are few photosynthetic products, few fruit set, and small fruit. If the tree vigor is strong and there are too many flower buds, in order to control the amount of flower and fruit, you may not apply fertilizer before flowering and change fertilizer after flowering.
After flowering, the top dressing is applied before the flowering period or after the flowering period. The purpose is to promote the growth of the branches and leaves, to create the conditions for flower bud differentiation and fruit enlargement, and to overcome the third fruit drop due to lack of nutrients. However, the amount of fertilizer should not be too much, the fertilization period should not be too late, so as not to cause new shoots excessive, affect the increase of flower buds and fruits.
Fruit enlargement fertilizer: It is usually applied when the growth of spring shoots is slow until the growth of spring shoots is stopped. In addition to nitrogen fertilizers, phosphorus and potash fertilizers, especially potassium fertilizers, are also used. After the spring shoots stop growing, nutrients are mainly used for vigorous root growth, increase leaf color, and increase photosynthesis intensity, thereby promoting flower bud differentiation and fruit enlargement. In production, the amount of post-harvest fertilizer is often increased, and the fruit enlargement fertilizer is postponed until one month before fruit harvest. This has a good effect on the growth and development of flower buds and the later increase of fruit.
Post-harvest fertilizer: This time, the fertilizer was applied in the middle or late September after it was deciduous after fruit picking. The main role is to improve the function and longevity of the leaves, promote photosynthesis, enrich the shoots and storage of nutrients, and lay the foundation for the next year's high yield. For nitrogen, phosphorus, and potassium, the proportion of nitrogen fertilizer is more important. This top dressing can also be applied together with organic fertilizer in the form of base fertilizer.
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