White rust infection and development significantly increased in the late sown (November) crop. The late sown crops sufferd greater damage (20 to 25%). The foliar infection usually appeared late in December when mean maximum temperature ranged between 24° to 26°C and mean minimum temperature remained lower than 10°C. The stagheads developed during the period of reduced sunshine 9.3 hr or near 10 hr per day for 24 to 72 hr during the flowering time conjugated with low temperature (maximum and minimum temperatures ranging between 24° to 29°C and 6° to 10°C respectively) and high humidity (70 to 85%). Rainfall plays an important role in the progress of disease, if occurs.
