Comparison of the Extent of Embryo Invasion by Loose Smut Mycelium and Adult Plant Infection in Artificially Inoculated Wheat

Field trial and laboratory experiment was conducted during crop season 2010–11 in which comparison of the extent of embryo invasion and adult plant infection of loose smut in sixty four genotypes of wheat were studied. On the basis of the amount of tissue invaded with mycelium, the embryos were classified into four groups i.e. 25, 50, 75 and 100 per cent embryo invasion. Out of sixty four genotypes twenty three genotypes i.e. 35% shows close correlation between the percentage of moderately to heavily infected embryos and percentage of smutted plants therefore, these genotypes were found to be susceptible towards loose smut infection. Twelve genotypes (19%) having 25–100 per cent embryo invasion, showed high susceptibility towards loose smut infection. Twenty eight per cent genotypes having 25–100 percent embryo infection but there was no adult plant infection and showed high resistance in the field. Remaining genotypes had upto 50% embryo invasion and mycelium couldnot be transmitted to adult plants this indicates some degree of resistance in the genotypes. Similarly, HS 365 having 75–100 per cent mycelium invasion in embryo, showing adult plant resistance but embryo susceptible.