بررسی میزان بیماری های مرگ گیاهچه و پژمردگی ورتیسیلیومی و عملکرد پنبه در روش کاشت فاصله ردیف بسیار باریک (UNR)

Yield increase due to high density, regardless of climatic conditions has been emphasized in some reports. Faster plant growth reduces population of weeds and water evaporation after irrigation but increases light absorption and leaves growth. This study was carried out in RCBD and three replications and two planting densities by 25 and 80 cm between lines and three varieties of cotton, including Sahel, Golestan and Sepoid in 2011-2012. The combined analysis of Verticillium wilt and seedling disease were not significant but Sepid variety had the lowest Verticillium wilt disease. The treatment was significant in first harvest, but in second harvest was not significant. Sahel verity has the lowest yield in the first harvest and Golestan variety in the second harvest. The index of verticillium wilt was significant in the first year of planting and cultivar. In the first year, the amount of characteristics such as the index of verticillium wilt disease, the first yield and total yield at a row distance of 25 cm was less than 80 cm. The percentage and severity of verticillium wilt disease of the Sepid variety were less than two other cultivars in the first year. In the second year, seedling disease was not significant in any of the treatments. First and total yields were significant in row distance and cultivars. In the second year, the Sahel cultivar had the lowest yield in first and total yields. In composite analysis between two years, the index of verticillium wilt was significant in cultivars and Sepid variety had the lowest percentage of the disease. In row distance and cultivar treatments, the first yield was significant, Sahel had the lowest first yield and Golestan had the lowest second yield.