Crop rotation is the basis for stabilization of soil fertility and crop productivity

In Ulyanovsk research Institute to determine the impact of different types of crop rotation to increase crop productivity and increase the economic efficiency of grain production were performed in 2014-2018. In stationary experiments studied the influence of different crops in crop rotations on the main agrophysical parameters of fertility, weeding and crop rotation productivity. The soil of the experimental site is leached Chernozem, medium-thick, humus content 6.35%, pH of salt extraction 6.8, the sum of absorbed bases 48.6 mg. EQ./100 g of soil, phosphorus 22.5 and potassium 11.9 mg / 100 g of soil (according to Chirikov). It is established that the grain-grass crop rotation provides a favorable water-air regime of the soil and its density. Cultivation of grain crops, in a grain-grass crop rotation using legumes, legumes-cereals and spring crops with sowing of perennial grasses (alfalfa) according to the generally accepted system of fertilizers allows to increase their productivity, to obtain the highest yield of grain, fodder units from 1 hectare of the crop area and ultimately the content of digestible protein in 1 K. units.