Genetic resource evaluation of groundnut (Arachis hypogaea L.) for resistance to tikka leaf spot

Abstract

The research project " Genetic resource evaluation of groundnut Arachis hypogaea L.) for resistance to tikka leaf spot was carried out at the College of Horticulture, Kerala Agricultural University, Vellanikkara, during 1988-89. Two hundred and fifty six groundnut genotypes available in the Department of Agricultural Botany were made use of for the study. A susceptible variety- TMV 2- was used as control. A field screening study was conducted with the 257 genotypes during July- November 1988, in arandomised block design with two replications. Disease rating was done with the aid of a diagramatic chart and the groundnut accessions were grouped into different categories such as immune, highly resistant, resistant, moderately resistant , moderately susceptible, susceptible and highly susceptible , based on the percentage of infection on leaves . Out of the 257 genotypes used for screening studies, four genotypes were moderately susceptible , 197 susceptible and 56 highly susceptible to tikka leaf spot. None of the varieties was immune highly resistant or moderately resistant.