The efficiency of using siderate crops in increasing soil fertility and yield of potato

Toshtemir Ostonakulov, Nosir Usmonov

Abstract: The purpose of the research is to study the influence of various siderate crops on the growth, development, yield formation, yield and seed quality of potato varieties, as well as soil fertility elements, and on their basis the selection of the best siderate and varieties, allowing to obtain a stable high healthy seed potato. In 2016-2019, studies were carried out on old-irrigated medium loamy typical gray-earth soils with a groundwater table of 5-7 m. The soils were characterized by favorable agrophysical properties and a low content of humus, nitrate nitrogen, mobile phosphorus, and an average content of exchange potassium. We studied early ripe varieties Kuvonch-1656m, mid-early varieties Bahro-30, Sante and Kondor for the following summer and winter siderates - rapeseed, oil radish, barley, peas, mustard, and peas+oil radish. Winter plowing served as control. The highest biomass productivity (29,9-34,5 t/ha) was observed in summer and winter siderate crops - peas, rapeseed, oilseed radish and pea+oil radish. With these siderates, the proportion of macroaggregates (>0,25 mm) in the 0-30 cm layer was 1,6–8,6 (summer), 5,8–9,6% more (winter), and the bulk mass was 0,04– 0,07 g/cm3 lower in comparison with the control. After the best siderates (peas, rapeseed and peas + oil radish), the humus content in the arable layer increases by 0,01-0,02%, nitrate-nitrogen 7,40-10,05 mg/kg, mobile phosphorus 14,4-16,3 mg/kg, potassium exchange 10,36-21,10 mg/kg compared with the control. Potato planting after selected siderate crops the germination of seed tubers was 99,6-99,9% by variety, seedlings were accelerated by 2-6 days, and the growing season was extended by 4-8 days, the leaf surface area was 20,6 - 21,7 thousand m2 more, the harvest of tubers from the bush is 206,0-223,7 g more than the control. At the same time, the highest yield of marketable (30,0-35,0 t/ha) and seed tubers (21,5-25,4 t/ha) with a reproduction ratio (6,5-7,7) was obtained. When planting seed tubers of the studied potato varieties grown after the best siderates (peas and peas + oil radish), it was found that the infection of plants with viruses decreased by 9,7-10,2% (in the explicit form), and in a latent form by 21,9 -22,2%. The proportion of degenerated tubers decreases by 3,0-3,4% and contributes to a healthy harvest of seed potatoes.

Keywords: potato varieties; productivity; reproduction coefficient; seed quality; Siderate crops

Date published: 2020-06-30