DEEPTI SADANA AND NIDHI DIDWANIA
Abstract
Early blight caused by Alterneria solani is most calamitous disease capable of damaging tomato plant in all developmental stages. Field surveys of tomato crop were conducted in replicated trials during 2014 and 2015 to recognize the early blight disease symptoms in all the vegetable growing areas of Faridabad, India. Evaluation was done in Rabi seasons at vegetable research farm of Integrated Pest management (IPM), Faridabad India. Eleven tomato genotypes were used in this investigation to analyze the susceptible and resistant genotypes selected under field conditions. The disease severity and percent disease index of Alterneria blight on leaves of different tomato genotypes varied from 34.68 to 46.14% (2014) and 37.91 to 52.20% (2015) from village to village in Faridabad district respectively. Mean AUDPC (Area under disease progress curve) of Alterneria blight on leaves of different genotypes of tomato under farmer field conditions during year 2014 ranged from 226 to 401. Analogous differences were also found in 2015 and mean AUDPC ranged from 334 to 431. Maximum AUDPC of Alterneria blight on leaves of 401 in 2014 and 431 in 2015 was exhibited by genotype Arun (HAU Hisar). Three genotypes of tomato viz. Indam 3001 (Ando American Hybrid seeds), Namdhari NS 524 and US 1080 (US Agri) were found moderately resistant after transplanting of 85 days in 2014. Arun (HAU Hisar) was found highly susceptible under both green house and field conditions in 2014 and similar results were also found in 2015.