Study on the incidence of Plutella xylostella population in different levels of nitrogen fertilizer on cabbage

The experiment on the incidence of Plutella xylostella in cauliflower in different levels of nitrogen on six cauliflower cultivars, revealed that diamondback moth population was significantly higher on cauliflower cultivar, Pusa Himjyoti during both the year. The incidence of insect pest of cauliflower was significantly higher at 100 kg/acre N fertilizer dose as compared to 75 kg and significantly lower population found in 25 kg/acre N dose. The lowest population of diamondback moth was recorded on Snowball-16 (0.16 larvae/3 leaves) and PSB-1 (0.10 larvae/3 leaves). Diamondback moth population showed significantly positive correlation with maximum and minimum temperature. Whereas relative humidity was significantly negative with larval population. Rainfall had significantly positive correlation with population of diamondback moth.