Effects of Three Biological Products on Rice Sheath Blight Disease in the Field

Sheath blight is an important rice disease in the Mazandaran Province of Iran. Biological control of this disease as alternative of chemical control with propiconazol (Tilt) fungicide, examined with 3 biological products, Trichodermin AB, Trichodermin B and Subtilin produced in Iran. At first in the laboratory, fungi and bacterium isolated and purified from these products, and their ability for antibiosis and hyper-parasitism, of pathogen evaluated. Then effect of these products comprised with Tilt in the field on Fajr cultivar in completely random block design with 4 replicates. Disease severity and damage, plant infection height, one thousand seeds weight, mean of tillering, yield and height of plant estimated. The results showed, applying Trichodermin AB can significantly decrease disease severity rate and damage, and prevent reduce of 1000 grains weight. At the level of healthy control and more better than fungicide propiconazol. Therefore it can introduce to farmers as suitable alternative of chemical control. Efficacy of this biological product for control rice sheath blight disease report for the first time from Iran.