Abstract
Y.G. Mishchenko*, E.A. Zakharchenko, S.I. Berdin, O.V. Kharchenko, E.R. Ermantraut, I.M. Masyk and V.S. Tokman
Weeds in potato crops have a negative effect on potato yield, especially in organic farming, so the present study aim find the most effective methods of reducing of weed infestation growing potato. A field experiment was conducted in the experimental plots at Sumy National Agrarian University in Northeastern Ukraine. Oilseed radish was grown for green manure use, after winter wheat harvesting, from August to October. Two methods of growing potatoes was studied-with application of green manure or without. In addition, four different types of tillage were studied: the control-moldboard ploughing at a depth of 28-30 cm, sweep ploughing at a depth of 28-30 cm, disking at a depth of 13-15 cm and 6-8 cm. It was found that green manure made from oilseed radish significantly decreased weed infestations and weed weight, especially of early weeds and winter weeds. The largest reverse correlation was observed between phytomass of oil radish and weed infestation (r=-0.76 and-0.75) and weed weight in potato sowings (r=-0.59 and-0.55) with moldboard ploughing or sweep ploughing methods at a depth of 28-30 cm. A decrease in tillage depth led to a significant increase in weed infestation, in the weight of potato crops, and a decrease in tuber yield-1.8-6.2 t ha-1. The method of tillage had a greater influence on the weed infestation-34 and 46% compared with the application of green manure-29 and 39%. According to data from the experiment, the application of green manure made from oilseed radish, along with the usage of sweep ploughing and disking, reduces the potential amount of weed seeds in the 0-30 сm deep root soil layer. The sweep ploughing at a depth of 28-30 cm with green manure application reduces the effect of potato overgrowth with weeds and helps to get the largest crop yield-up to 30.3 t ha-1.