Cabbage development and associated lepidopterous pest complex in the southern USA

Abstract

The cabbage variety ‘Greenback’ was grown using similar cultural practices at three locations across the southern USA during a 2-year period. Leaf production, plant development and lepidopterous pest populations were monitored and correlated to heat units as degree-days. Results indicate that significant quadratic and linear relations exist between leaf production and degree-days and that a robust linear model can be used to describe leaf production across the southern region of the USA. Pest populations differed in abundance and species composition among locations and between years. Findings indicate that the greatest variability in population abundance may be due to pest immigration from alternate hosts; therefore, pest management strategies may be most reliably based on weekly or twice-weekly scouting of fields, rather than expending efforts on trying to predict populations from models based on heat units and previous population abundance in individual fields.