Identification of resistant sources against early blight disease of tomato

Abstract

One hundred forty two tomato genotypes including wild and cultivated lines were screened for resistance against early blight disease caused by Alternaria solani. Evaluations were conducted in vivo and in vitro for disease severity and host resistance of the plants. Eight lines (EC-520057, EC-520058, EC-520059, EC-520061, EC-508765, EC-538394, H-88-78-1 and EC-501583) showed highly resistant reaction against the fungus; three lines were found resistant, 5 lines moderately resistant whereas 33 lines showed moderately susceptible besides 57 susceptible and 36 highly susceptible lines against the disease under natural epiphytotic condition. Screening under in vitro, revealed that eight genotypes were highly resistant, 3 resistant and 7 as moderately resistant. It was found that the accessions of wild relatives of tomato were highly resistant which may be utilized for the development of pre-bred lines or recombinant inbred lines or in other molecular research activities for the improvement of tomato. Some of the cultivated genotypes as resistant/moderately resistant under in-vivo and in-vitro like H-86, VRT-2, NC EBR-4 and RCMT-1 may directly be promoted for growing in disease prone areas.