The article presents the results of a study of onion of different varieties for the content of nitrogen and phosphorus in it. As a result of the study, a highly significant interaction between nitrogen and phosphorus was established: the increase in yield from the introduction of one element was determined by the level of the content of another element. Under conditions of phosphorus deficiency, increasing levels of nitrogen first increased the yield, and then reduced it. With an insufficient supply of phosphorus, the introduction of nitrogen led to a more significant increase in yield. The effect of the combined use of these elements was greater than the sum of the effects of the separate introduction of each of them. The use of chemical analysis of plants for the diagnosis of their nutrition is based on the relationship between the mineral composition and plant yield and on the fact that between the amount of any nutrient in the soil and its concentration in plant tissues there is a direct relationship to the comparison of the results of a particular analysis with previously established standard values.

Cherkashina Mariya I., Alimgafarov Rail R., Kuznetsov Igor Yu., Cherkashina Anna G.

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