1. Fertilization time is too late
More than half of the orchard farmhouses applied organic fertilizer too late, which was postponed to late November to late January (winter), and some even applied organic fertilizer in spring.
2, raw manure into the ground
Nearly half of the farmhouse organic manure used in orchards has not been fully fermented and matured. Some fruit farmers buy raw cow manure or chicken manure from dairy farms or chicken farms in autumn, winter or spring, or simply use it after pulling human manure from urban public toilets or cottage latrines. There is a high concentration of uric acid in raw manure and urine, which is very easy to burn fruit tree roots. The root burning is very serious. It is a very strong transport root and capillary root group, which is very dangerous to kiwifruit trees.
3. Excessive application of chemical fertilizer
One sided orchards do not apply organic fertilizer, but rely on chemical fertilizer. As a result, the content of soil organic matter is seriously insufficient, the soil fertility of orchards drops, the soil hardens seriously, and the root growth of kiwifruit continues to deteriorate. Eventually, the tree vigor becomes weaker and weaker, resulting in shorter life span. 2、 Problems in topdressing
1. It is difficult to master the time of topdressing chemical fertilizer
Because of the lack of physiological knowledge of kiwifruit trees, the fruit growers can not apply the fertilizer according to the demand of N, P, K and other mineral nutrients in different growth stages of kiwifruit.
2. Excessive or insufficient Topdressing of chemical fertilizer
It is not reasonable to determine the amount of fertilizer according to the age of trees. For example, excessive application of ammonium bicarbonate when topdressing budding fertilizer, some fruit farmers topdressing ammonium bicarbonate more than 2-2.5 kg per fruit tree, some fruit farmers topdressing ammonium bicarbonate 1-1.5 kg and calcium superphosphate 2.5-3.0 kg per plant at the end of autumn and the beginning of winter after fruit harvest. Excessive phosphorus will fix the limited zinc element in the soil, so that the fruit trees will grow in the next spring Growth retardation, physiological disease. Some did not see the consequences of fruit trees, reluctant to invest, do not apply chemical fertilizer or less fertilizer and reduce the frequency of fertilization, affecting the normal growth of fruit trees.
3. The ratio of support to distribution is unbalanced
(1) Fertilization is not targeted. In addition, the kiwifruit orchard will also apply any chemical fertilizer. Some use ammonium bicarbonate, urea, calcium superphosphate, potassium chloride and other fertilizers as important fertilizers. They do not mix with each other, and they use a large number of elements of nitrogen, phosphorus and potassium throughout the year regardless of season. The ratio of a large number of elements and nutrients is not balanced, which seriously affects the application effect of chemical fertilizer. (2) The ratio of a large number of element nutrients to medium and trace element nutrients in soil is out of balance. With the increase of tree age and yield, there is a lack of trace elements. However, fruit growers only know the excessive Topdressing of nitrogen, phosphorus and potassium, but they know little about the physiological functions and importance of medium and trace elements. The ratio of a large number of elements to medium and trace elements is extremely unbalanced, which reduces the ability of fruit trees to resist freezing, cold, drought and high temperature, and affects the yield and quality .
4. Lack of inquiry on the efficacy of chemical fertilizer varieties
At present, there are many kinds of chemical fertilizers, including dozens of simple chemical fertilizers, compound fertilizers, organic fertilizers, organic and inorganic mixed fertilizers, medium and trace element fertilizers, microbial fertilizers, etc. When fruit farmers buy chemical fertilizer, they are often greatly influenced by the merchants. One sided merchants recommend fertilizer to fruit farmers only for high profits, and seldom ask about the effect after application. However, countless fruit farmers only ask about the cost of chemical fertilizer, regardless of the nutrient content, and only want to save money.
5. The formula of NPK is different
At present, the formula of nitrogen, phosphorus and potassium of some fertilizer enterprises has different effects on the growth of kiwi fruit trees. For example, before the cell division and young fruit expansion of kiwifruit (late May to late June), the nutrient ratio of kiwifruit trees at this time is low nitrogen, medium phosphorus and low potassium (n 16%, P 25%, K 18%). However, the formula of N, P and K is 22%, 5% and 23%, that is, high N and high K. Simple application of apple, pear and other fruit tree formula, resulting in the effect of kiwifruit fertilization is getting worse and worse.
6. Half of the orchards did not face up to foliar spraying
The variety, concentration, frequency and time of foliar fertilizer spraying were not scientific.