Application dates of ammonia nitrate in cultivation of brown mustard as a green manure crop

In the southern regions of the Russian Federation, there has been a sharp decline in livestock production due to its low profitability. As a result, many farmers lack organic fertilizers, which are difficult to replace fully with mineral fertilizers. In addition, mineral salts cause negative processes (peptization, coagulation) in the soil profile, which worsen the physical and physical and chemical properties of the soil and its fertility in general. However, a good source of soil organic matter is not only livestock waste, but also plant residues or so-called green fertilizers. In this regard, in 2021-2022, we studied the effect of ammonium nitrate on the yield of green mass of brown mustard (Brassica juncea L.) variety Yunona on leached black soil of the Western Ciscaucasia on the fields of V.S. Pustovoit All-Russian Research Institute of Oil Crops (Krasnodar, vil. Oktyabrsky). The purpose of the research was to assess fertilizing value of ammonium nitrate (ability to return the elements of mineral nutrition at full green manuring of plants). It was found that the highest efficiency of the nitrogen fertilizer application is achieved with a single application of N30 at the seedling stage of mustard. With this specific method of N30 application, more green mass and dry biomass are incorporated into the soil, by 10.6 t/ha and 3.34 t/ha, respectively, compared to the control. At the same time, the yield of macroelements is also higher: nitrogen - by 64.3 kg/ha, phosphorus - by 14.3 kg/ha, potassium - by 155.3 kg/ha, and the estimated amount of newly formed humus increases by 0.7 t/ha comparing to control.