Optimum Sowing Norms of Sunflower of Rodnik Variety Depending of Mineral Nutrition Background on Grey Forest Soils of the Middle Volga Region

Abstract

We can expect to receive from 0.81 to 0.97 tons of sunflower oil seeds per hectare in the soil-climatic conditions of the forest-steppe zone of the Middle Volga region without the introduction of mineral fertilizers. As the doses of mineral fertilizers are increased, the productivity of 1 hectare of arable land is increased 2.8 times and the gross collections of oilseeds are 2.14 tons per hectare at the non highest background of mineral nutrition, against 0.86 tons per hectare in the control variant of the experiment (without fertilizers). The optimization of seeding rates of the studied culture is of great importance in the formation of highly productive agrocenoses. In the variants of supplementary supply of plants with nutrients, especially when N98P38K124 is introduced, the seeding rate of 70 thousand pieces per hectare of virgin seeds raises the yield of sunflower by 0.51 tons per hectare (a very solid increase in yield), compared with the sowing rate of 60 thousand pieces per hectare.