An experiment on the population fluctuation of the diamondback moth;
Plulella xyloslefla (L.) and the cabbage looper; Trichop/usia ni (Hubner) on cabbage
was carried out at EI-Manawat village, Giza Govemorate along two succes~ive
seasons; 2001·2002 and 2002-2003. Results revealed that the diamondback moth
was abundant during fall and the beginning of winter, while the cabbage looper
occupied summer and fall seasons throughout the two seasons of study. Two high
peaks of the former pest population (eggs, larvae and pupae) occurred from the
second week of September to the last week of November, as compared with three
peaks for T. ni; in the second half of July, along September and from the second half
of October to the first half of November. The two insects were rare through January
and February.