Effect of planting dates and tomato cultivars on intensity of early blight caused by Alternaria solani

The effect of different dates of planting and cultivars on early blight disease intensity and yield of tomato was determined. Tomato crop was planted on three different dates during Kharif, 2011 (D₁: 20.07.2011; D₂: 05.08.2011 and D₃ 20.08.2011) and Rabi, 2011 (D₁: 20.11.2011, 05.11.2011 and 20.11.2011), using two cultivars Mahyco 5005 (Tolerant) and Pusa Ruby (Susceptible). During Kharif, 2011 maximum average disease intensity was recorded in the crop transplanted on D (05.08.2011) and minimum on D (20.07.2011) and D₂ Mahyco 5005 and recorded minimum average disease intensity of 32.02 (D₁), 32.11 (D₃) and 42.10 (D₁) percent; whereas Pusa Ruby recorded maximum average disease intensity of 36.58 (D₃), 41.46 (D₁) and 45.88 (D₂) per cent. During Rabi, 2011 minimum average disease intensity was recorded in crop transplanted on D₃ (20.12.2011) and maximum on D₁ (20.11.2011) and D₂ (05.12.2011). In both the tomato cultivars disease intensity from its first appearance was increased steadily and it was comparatively maximum in Pusa Ruby than Mahyco 5005. However, the yield of tomato was significantly higher in the crop planted during Rabi, 2011, as minimum disease intensity was observed than that of Kharif, 2011.