Published in Scientific Papers. Series "Management, Economic Engineering in Agriculture and rural development", Vol. 23 ISSUE 2
Written by Antoniya STOYANOVA, Darina STOYANOVA

The study was conducted in the period 2018-2020 in the Training and Experimental Base of the Department of Plant Breeding at the Faculty of Agriculture of the Trakia University - Stara Zagora on soil type typical meadow-cinnamon soil in fertilizer experience in non-irrigated and irrigated conditions. The field experience is by the method of fractional plots in four repetitions with the size of the harvest plot 15 m² (1.80 x 8.34 m). The research factors are: irrigation (A), variety (B), fertilization rates (C) and meteorological conditions during the marketing year (E). The study was conducted with three varieties of cotton - Helius, Darmi and Isabell, with three levels of nitrogen fertilization - 80, 160, 240 and 0. The effect of irrigation on cotton productivity has been established. As a result of the conducted Polish research, it was established that the total yield of unginned cotton realized on average for the research was very good – 1,945.2 kg/ha. The average yield under irrigated conditions exceeds the yield without irrigation by 34%. The Darmi variety stands out as the most productive and promising compared to Helius and Isabell. The optimal nitrogen rate of the tested is N160. When fertilizing with N₂₄₀, the yield shows a downward trend compared to N₁₆₀ and this fertilization is not effective. On average for the period, at the four levels of nutritional regime, the effect of 100 m³ of irrigation water was established – 89.81 kg/ha. With the naturally coloured variety Isabel, the effect is the highest, on average for 4 levels of fertilization – 100.75 kg/ha.

[Read full article] [Citation]