Correlation Between Initial Nematode Population Density and Crop Losses Caused by Heterodera avenae in Wheat

An experiment was conducted to find out the effect of different inoculums levels(0, 2, 4, 8 and 16 cyst/plant)H. avenae on wheat. Among different inoculums level, highest females/5 g root (32.75), cysts per 200 cc soil (43.07) and juveniles per 200 cc soil (358.75) were recorded in 16 cyst/plant whereas lowest were recorded in 2 cyst/plant. Maximum shoot length (79.85 cm), shoot weight (28.84 g), root length (32.10 cm), root weight (7.71 g), fodder yield (23.72) and grain yield (15.81) were recorded in uninoculated plants (0 cyst/plant) whereas minimum was at 16 cyst/ plant. Significant reduction in plant growth characters were observed at and above 4 cyst/plant. Hence, experimental result revealed threshold level of 4 cyst per plant on wheat.