The so-called nutritional diagnosis refers to the method of judging the nutritional profit and loss according to the chemical
The so-called nutritional diagnosis refers to the method of judging the nutritional profit and loss according to the chemical analysis results of nutrients contained in plants and soil. The commonly used nutritional diagnosis methods of fruit trees are as follows.
1. The diagnosis of external fertilization is to prepare a solution with a certain concentration (generally 0. 1% ~ 0.2%) and spray it on the leaves of diseased plants, or soak the diseased leaves in the solution by soaking or smearing 1 ~ 2 hours, and observe the changes of leaf color, appearance and growth potential.
If it is found that the diseased leaves have recovered or the birth speed of new leaves is obviously accelerated and the color of leaves is normal, we can determine what elements are missing.
2. Soil analysis and diagnosis: dig representative soil samples from the orchard, and determine various mineral nutrients, organic matter content and pH value through appropriate treatment and corresponding analysis. According to the analysis results, the profit and loss degree of a certain nutrient element can be judged, so as to determine the type and dosage of fertilization.
3. Morphological diagnosis of fruit trees is an intuitive and auxiliary nutritional diagnosis method, which judges the profit and loss of nutrition according to the appearance of fruit trees, and it requires fruit tree operators to have rich experience.
Usually, whether nutrition is normal or not is determined by the size of leaves, the thickness of leaves, the thickness of branches, the fullness of bud eyes, the growth state of branches, the fruiting state and so on. If there is any abnormality, measures should be taken to improve it.
4. Analysis and diagnosis of leaves The analysis and diagnosis of leaves are usually carried out on the basis of morphological diagnosis, especially when some elements are lacking and typical symptoms are not shown, further diagnosis must be made through leaf analysis. Generally speaking, the results of leaf analysis are the most direct reflection of the nutritional status of fruit trees, so the diagnosis results are accurate and reliable.
Leaf analysis is to analyze the element content of plant leaves, and compare it with the critical content or index (that is, the standard value of various element content of fruit tree leaves) drawn up in advance by experimental research to determine the lack or imbalance of some elements, and refer to the results of soil nutrient analysis to guide fertilization.