Use of Abiotic and Biotic Inducers for Controlling Fungal Diseases and Improving Growth of Alfalfa

Five biotic and abiotic inducers namely, (Bio-Arc and Bio-Zaid) and (salicylic acid, K HPO and neem 2 4 oil) were examined for their effectiveness in controlling fungal diseases, improving growth and yield of alfalfa. The field trials have shown that salicylic acid, K HPO and neem oil respectively gave a significant P 0.05 2 4 protection against rust, downy mildew in both tested cvs. Ismailia-1 and wade-1 when applied as plant spraying and/or seed soaking compared with check treatment, whereas, Bio-Zaid and Bio-Arc were less effective. Moreover, the tested inducers significantly decreased root rot and wilt severity and increased the number of nodules, fresh and dry weight of nodules per plant and yield components were increased over the control in both cultivars when applied as seed soaking. These results were confirmed in the two successive seasons2008/2009and 2009/2010 with minor differences. The mechanism under line induce disease resistance is discussed.