اثر روش هاي مختلف آبياري بر روي ميزان آلودگي بيماري هاي مهم پنبه در استان گلستان

The effect of different irrigation systems on the infection level of fungal pathogenic agents on cotton

In order to investigate of various irrigation methods on the infection level of important diseases on cotton, this study was carried out in randomized block design in Hashem-Abad Research Station of Gorgan during 1996-1997. Three irrigation methods including: sprinkler (classic and mini traveling gun) and furrow were considered in randomized block design with 3 replications. Severity of infection to Verticillium wilt, Rhizoctonia solani and Alternaria leaf spot diseases measured in different treatments and analyzed statistically. Results indicated that the effect of irrigation systems on cotton Verticillium disease were significantly different (P<0.05). Percentage of infections Alternaria macrospora was much higher in sprinkler systems(classic and mini gun more than in furrow treatments).lt was also found that severity infections of Verticillium dahliae was much higher in furrow treatment than in sprinkler systems. Sprinkling irrigation had no significant effect on the fungal diseases such as Verticillium, but they were increased the damage by Alternaria. Meanwhile, cotton infection to Rhizoctonia disease between three treatments were not increased during two years.