IDENTIFICATION OF CHROMOSOMES CARRYING GENES FOR RESISTANCE TO LOOSE SMUT OF BREAD WHEAT (TRITICUM AESTIVUM L.) IN INDIA

Abstract

The breadwheat variety Cadet and all its monosomic lines (except mono 3A) were inoculated with a mixture of loose smut chlamydospores. The inoculated seed was grown during normal (rabi) and off-season (summer) conditions. Cadet was found to be resistant to loose smut. Resistance was governed by at least three genetic factors located on chromosomes 18, 30 and 70. The gene on chromosome 30 was major. Genes on chromosomes 1 8 and 70 were modifiers whose hemizygous ineffectiveness resulted in slight weakening of the resistance of the variety (only one late tiller of these susceptible plants developed the disease). While the gene on 18 was effective during both seasons, the effect of the one on 70 was not discernible during the normal season.