Evaluation of lines and their hybrids against Early blight (Alternaria solani) in tomato.
Nitin kumar, Anil kumar, Ranbir Singh, Vinod Kumar, Rajendra Kumar Khanna

A B S T R A C T
Early blight (Alternaria solani) of tomato is one of the major biotic constraint in different ecologies the world. The highly loss in yield and quality of fruits leading to complete defoliation, are the most damaging in regions with heavy rainfall, high humidity and fairly high temperatures (24-29 ºC).The objective of this research was to compare between higher diseased incidence plant and lower diseased incidence plant based on yield as the measuring parameter in natural epiphytotic conditions. A line × tester analysis was conducted for evaluation of early blight disease of tomato in the Vegetable Research Farm, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi (India). Thirteen lines and thirty hybrids were screened in Randomize Block Design with three replications following standard spacing under natural epiphytotic conditions against early blight of tomato in two Rabi (winter) seasons 2009 and 2010.In 2009, the maximum disease severity was recorded for the hybrid NDTVR-60 × Kashi Sharad (42.66%) with a minimum severity of 24.00% in Flora dade x BT 12 however, in 2010 maximum disease severity was also recorded for the cross NDTVR-60 × Kashi Sharad (44.00 %) and minimum for Flora dade × BT-12 (24.00 %). In the year 2009, twenty-three hybrids were moderately resistant while six hybrids showed susceptible reaction and one of the hybrid (Flora dade × BT-12) showed resistant reaction for the early blight. In 2010, twenty-two hybrids showed moderately resistance and seven hybrids were found susceptible.Data showed higher disease incidence was responsible for decreasing yield per plant in both the years and also identifying resistant cultivars for further research work.

Full Text