How to identify the 11 common nutrient disorders in fruit trees? How to prevent it?

There are four commonly used nutrient diagnosis methods in <>, namely, identification of fruit tree deficiency symptoms, field experiments, soil nutrient diagnosis and leaf analysis.

1) Identification of fruit tree deficiency symptoms: It is to determine the surplus and deficiency of certain nutrients through the observation of deficiency symptoms. The method is simple, does not require any investment, and is widely used in production.

However, this method must be well practiced and can only be identified in the presence of typical symptoms, and should only be used as a reference.

2) Field experiment: It is the basic method of diagnosis and diagnosis, and it is also the basis of other diagnostic methods. The field fertilization test of fruit trees can be used for soil fertilization and root topdressing, and the advantage is that the actual response of fruit trees to fertilizer can be directly seen.

However, the test requires a lot of manpower and material resources, which is time-consuming and laborious, and should be used in combination with other diagnostic methods.

3) Soil diagnosis: The method of chemical analysis is used to quantitatively analyze the soil elements in the orchard, estimate the fertility level of the soil, and provide a basis for fertilization. This approach is indispensable for newly planted orchards and nurseries and serves as the basis for soil management and fertilization.

Mature orchards are mainly used to determine the status of various nutrients, but they cannot reflect the surplus and deficiency of tree breeding, so a diagnosis should be made every few years.

4) Leaf analysis: This is a simple and easy nutritional diagnostic method at present. Usually, the leaves of the new shoots and the middle of the fruit tree are taken to analyze the full amount of each mineral element, and the standard value and relative ratio value are used to determine the surplus and deficiency of fruit tree nutrition.

The accuracy is very high, and it can be used to guide fertilization for greater economic benefits. However, the cost is high, and it should be used in combination with soil diagnosis.

Summary. There are 6 kinds of nutrient antagonism in fruit trees, namely nitrogen, phosphorus, potassium, calcium, magnesium and sulfur.

There are 6 kinds of nutrient antagonism in fruit trees, namely nitrogen, phosphorus, potassium, calcium, magnesium and sulfur.

For the growth of fruit trees, all 17 essential nutrients are indispensable, and the absence of any one element will cause the corresponding disease and appelmatism, and this element cannot replace the role of the other. First of all, the macro elements carbon, hydrogen, oxygen, these three elements are God free and free gifts and wealth to fruit farmers and friends, fruit trees rely on their own breathing and rain and snow supply can be supplemented, and these three elements to friends of the acacia accounted for more than 90% of the overall proportion of fruit trees, so the management of the orchard is mainly to reflect the four balance difference words: ventilation and light.

Secondly, the remaining elements containing less than 10% must be manually replenished. According to the different utilization rates of fruit trees, people divide them into a large number of elements: nitrogen, phosphorus, potassium; Medium Element:

silicon, calcium, magnesium, sulfur; Trace elements: iron, boron, copper, manganese, molybdenum, chlorine, zinc.

"Nitrogen" is the (life) element; "Phosphorus" is the (energy) element; "Potassium" is the (quality) element; "Silicon" is the (conductive) element; "Calcium" is the (epiphotological) element; "Magnesium" is the (photosynthetic) element; "Sulfur" is the (flavor) element; Lack of "iron" (yellow leaf disease); "Zinc" deficiency (lobular disease); lack of "molybdenum" (mosaic disease); lack of "copper" (early defoliation and peach gum disease); Lack of "boron" and "zinc" affect fruit set; "Manganese" is often poisoned (rough derma); Fruit trees (especially peach trees and grapevines) are avoid "chlorine" crops, and the best fruit tree fertilizer has a "chlorine" content of 3%. There is not only a synergistic (promoting) but also antagonistic (inhibiting) effect between elements. For example, "nitrogen" inhibits the absorption of "potassium, iron, boron, zinc, magnesium, calcium"; "Nitrogen, phosphorus and potassium" antagonize the absorption of "iron, boron, and zinc-magnesium".

If you understand the synergy and antagonism between the elements, you can understand the combination and utilization of fertilizers, and avoid many misunderstandings. All kinds of plants due to different growth habits, in the return of different seasons of the favorite elements are also different, if plant protection is medicine, pay attention to the treatment of diseases, then soil fertilizer and water management is nutrition, pay attention to disease prevention. The management of fruit trees is like the management of our daughters, not only to dress up (plastic pruning), but also to see a doctor and take medicine (pest control), but also to eat and nourish (soil fertilizer and water management), so plastic pruning is the foundation, pest control is the key, and soil fertilizer and water management is the guarantee.

<> so-called nutritional diagnosis is a method of determining the nutritional deficit status based on the results of chemical analysis of the nutrients contained in plants and soil. The commonly used nutritional diagnosis methods for fruit trees are as follows.

The specific method is: prepare a certain concentration (generally 0 1 0 2) solution containing a certain trace element, spray it on the leaves of the diseased plant, or use the method of soaking and smearing, soak the diseased leaves in the solution for 1 2 hours, and observe the changes in the color, appearance and growth potential of the leaves.

If the diseased leaves are found to have recovered or new leaves are born at a significantly faster rate, and the leaf color is normal, it can be determined that the deficiency is the cause.

A representative soil sample is dug from the orchard, and after appropriate treatment and corresponding analysis, various mineral nutrients, organic matter content and pH are determined, and according to the analysis results, the profit and loss degree of a certain nutrient element is judged, so as to determine the type of fertilization and the seepage section of the fertilizer amount.

Morphological diagnosis is an intuitive auxiliary nutritional diagnosis method, which is based on the appearance and morphology of fruit trees, to judge the profit and loss of nutrition, which requires fruit tree operators to have rich experience.

Usually, the nutrition is normal by the leaf size, leaf thickness, branch thickness, bud eye fullness, branch growth state, fruiting state, etc., and if there is an abnormality, measures should be taken to improve it.

The diagnosis of leaf analysis is usually carried out on the basis of morphological diagnosis, especially when a certain element is deficient and does not show typical symptoms, it is necessary to use the leaf analysis method to further confirm the diagnosis. Generally speaking, the results of leaf analysis are the most direct reflection of the nutritional status of fruit trees, so the diagnosis is accurate and reliable.

The leaf analysis method is to analyze the elemental content of plant leaves, and compare them with the critical content or index (i.e., the standard value of various elements in fruit tree leaves) formulated by experimental research in advance, so as to determine the deficiency or imbalance of certain elements, and refer to the results of soil nutrient analysis to guide fertilization.

When fruit trees lack any of the essential elements, their physiological metabolism will be impaired, thus showing certain symptoms in appearance. There are many causes of nutrient deficiency, but the following are common. 1.

Deficiency of soil nutrients is the main cause of nutrient deficiency in soil. Generally, when the content of a certain element in the soil is low to a certain level, it will cause fruit tree deficiency disease.

2.Poor soil physical and chemical properties and other factors affect the availability of nutrientsDrought, soil pH discomfort, adsorption fixation, uncoordinated elements, poor soil physical and chemical properties, etc., reduce the availability of nutrients, resulting in the normal absorption of fruit trees.

3.The effect of adverse climatic conditions is mainly low temperatures. On the one hand, low temperature slows down the transformation of soil nutrients, and on the other hand, weakens the ability of fruit trees to absorb nutrients, so low temperature can easily cause the occurrence of nutrient deficiency.

Usually cold spring is prone to various deficiencies. In addition, the amount of rainfall and sunlight also have a significant impact on the occurrence of nutrient deficiency.

4.Unreasonable fertilization is mainly due to the failure to safely fertilize according to the law of fertilizer demand of fruit trees, the characteristics of soil fertilizer, the nature of fertilizer types and their ratios, resulting in insufficient or excessive land fertilizer supply, which brings negative impacts.

5.There are three main situations of poor soil management in orchards, soil compaction, improper soil moisture regulation, and improper soil modification, which make soil nutrients unavailable or affect the normal absorption of roots, resulting in a lack of certain elements.

6.The failure to plant trees in the right place is mainly due to the failure to arrange the planting of fruit trees according to the nature of the soil, resulting in nutrient deficiency.

7.The influence of pests and diseases can lead to nitrogen deficiency, phosphorus deficiency, boron deficiency and zinc deficiency in apple rot and root rot. Underground pests such as nematodes, needleworms, grubs and tigers can lead to nitrogen and phosphorus deficiency in strawberries and zinc and iron deficiency in apple seedlings. The presence of pathogens such as fungi in the soil, which can easily lead to iron deficiency; Severe root trauma or plough injury can also lead to nitrogen and phosphorus deficiency; Grafting of round-leaved and trifolium rootstocks with scion with green leaf spot and black poxvirus can lead to boron deficiency.

8.Improper cultivation techniques, excessive retraction and pruning, excessive peeling, too large loads, improper rootstock selection and rootstock combination, etc., can also cause fruit tree deficiency.

Nutrients are the main nutrients to maintain the normal physiological activities of fruit trees, such as nitrogen, phosphorus, iron, zinc, boron, magnesium, calcium, copper, manganese, molybdenum, etc., some are components of the tree, and some can regulate the metabolic function of the tree, which is very important for the normal development of the tree.

However, the fruit tree has a certain range of requirements for each element, when suitable, the growth and development is normal, if a certain element is lacking or too much, it will cause the disorder of the physiological function of the fruit tree, the appearance of symptoms, affect the yield, and even make the tree seriously weakened and even die. Although some elements are slightly deficient, and the appearance of fruit trees does not show obvious symptoms, the internal physiological functions have been inhibited, which will also affect the tree momentum and reduce the stress resistance of fruit trees.

The external symptoms caused by the imbalance of the same nutrient element are not exactly the same in different fruit trees.

1 Symptoms of calcium deficiency.

Calcium deficiency in fruit trees first causes damage to the root system, the root tip stops growing, the root system becomes smaller, and root rot often occurs. The young leaves in the shoots are distorted, the leaf margins are deformed, the leaves are often spotted or necrotic, and the terminal buds are easy to die.

The symptoms of calcium deficiency in several major fruit trees are shown in Table 5-7.

Table 5-7: Symptoms of calcium deficiency in several major fruit trees.

2 Symptoms of excess calcium.

Too much calcium in the soil can raise the pH, which can affect the effective absorption of other elements such as iron, zinc, manganese, boron, copper and phosphorus.

Dicalcium phosphate, spray once every 5 7 days, spray 2 3 times. If the soil is too acidic, calcareous fertilizer should be applied to the soil, or lime, gypsum and organic fertilizer should be mixed, and about 75 kg per hectare should be applied. For orchards with serious calcium deficiency, nitrogen and phosphorus source fertilizers should be applied at the same time.

When there is a surplus of calcium in the orchard soil, acidic or physiologically acidic fertilizers should be used. Especially for calcareous soils, sulfur powder can be applied directly at a rate of 210 kg per hectare.