Impact of Soil Sterilization on Common Bean Reaction to Anthracnose : Effects Of Steam-Sterilization Of Soil On Common Bean Genotypes (Phaseolus Vulgaries L.) Reaction To Anthracnose Disease

Soil sterilization in screenhouse experiments eliminates the effect of soil pathogenic microbes where reaction of plants to artificial inoculum is being investigated. The objective of this study was to evaluate the effect of soil sterilization on 10 common bean genotypes reaction to the anthracnose pathogen under screenhouse conditions. The experiments were conducted at KARI-Kakamega. Bean seedlings were planted in both sterile and non sterile potted soils and inoculated 10 days after germination. Data on growth parameters, disease incidence and severity (CIAT 1-9 scale) was collected. Data was analyzed using the SAS statistical software (version 9.1). Of the 10 genotypes, 5 showed high levels of resistance to C. lindemuthianum of 3 while the other five genotypes were tolerant. Soil sterilization altered the performance of the plants, but did not significantly affect their reaction to anthracnose. Notwithstanding, non-sterile soil should be used alongside sterile soil for screenhouse experiments when evaluating for anthracnose disease.