Field application of bio compost to control Fusarium dry rot disease of potato in newly reclaimed lands.

Fusarium dry rot caused by Fusarium sambucinum could infect all cultivated potato cultivars at different degrees of disease infections. Laboratory and field trails were carried out for controlling the causal organism and disease incidence. Fusarium sambucinum isolate No.3 was highly pathogenic to all potato cultivars. Trichoderma harzianum was antagonistic to all tested isolates with different degrees of inhibition. Trichoderma harzianum inhibited the linear growth of all tested isolates of F. sambucinum by overcoming their growth. Drenching soil before tuber sowing with bio compost 4 (composted bagasse + rice straw + soybean straw + T. harzianum) and/or bio compost 1(composted bagasse + T. harzianum) significantly reduced Fusarium dry rot disease incidence and its severity .Compost 1 and compost 4 reduced disease incidence and severity by 58.2, and 68.7% and 65.9 , 68.1% during the first cultivation seasons 2010 and by 60.7, 71.4 % and 73.1, 78.0% during the second cultivation season 2011. These treatments increased the obtained tuber yield/ feddan by 64.7 and 55.6 % in the first plantation 2010 and by 77.7 and 59.2% in the second plantation 2011.Therefore, the usage of composted agricultural wastes fortified with bio control agents could be suggested as easily soil biotreatment for controlling dry root rot as well as soil borne pathogens of potato especially under organic system.