Abstract

Nitrogen management is a challenging task and several methods individually and in combination are in use to manage, nevertheless, nitrogen use efficiency has not been ameliorated to a level as predicted by the researchers while developing nitrogen management tools and methods. The experiments were carried out from 2012 to 2014 on meadow-chestnut heavy loamy soil at “Bikesha” farm in Tarumovsky district of the Republic of Dagestan, Russia to study the influence of previous crops which include winter wheat for green manure and fodder production, row crops and alfalfa on the winter wheat. Six treatments used in the experiment were winter wheat-three years without rotation, winter wheat-two years without rotation + natural phytocenosis for green fertilizer, winter wheat-two years without rotation + natural phytocenosis for fodder production, corn for grain, sunflower for seeds and alfalfa for hay. Nitrogen concentration in the phytomass during harvesting of precursors was determined before ploughing and mowing the natural phytocenosis for fodder production. The results showed that the maximum content of plant material in soil (25.82 t/ha), the highest nitrogen concentration (2.18 to 3.32%) and higher productivity of winter wheat (4.67 t/ha) were demonstrated when the previous crop was alfalfa and natural phytocenosis. These findings can be used to design crop rotations enriched with the main food crop of up to 80 to 100% without compromising crop yields and soil fertility in small farms, which have a small set of crops, as well as insufficient material and technical resources.