Population Fluctuations of Some Aphid Species Infesting Maize Plants in Sharkia Governorate

Abstract

The results showed that three aphid species namely Rhopalosiphum maidis, R. padi and Aphis gossypii infesting maize plants in Sharkia governorate. R. maidis was the most abundant species on maize plants during 2008 and 2009 seasons. The highest population densities occurred in 3 rd week of August for all districts i.e., Zagazig, Belbeis, Abou-Hammad and Meniet El-Kamh whereas their values were 1279.80, 955.45, 544.32 and 1095.06 aphids/plant, respectively during the first season. But during 2009 it appeared with higher population (1399.99, 820.79, 506.06 and 598.79 aphids/plant). On the other hand R. padi reached its peak during 3 rd week of August with (423.83, 640.63, 395.78 and 234.76 aphids/plant) for season 2008 and during 2009 it appeared with (297.32, 640.63, 395.78 and 276.66 aphids/plant) for Zagazig, Belbeis, Abou-Hammad and Meniet El-Kamh, respectively. In addition A. gossypii indicated its peak on 4 th week of August with values of 343.36, 372.03, 378.56 and 457.30 aphids/plant, respectively for the same previous districts at the first season and (338.03 &395.36 aphids/plant) for Zagazig and abou-Hammad at 1 st week of September and (418.73 &357.96 aphids/plant) for Belbies and Meniet El-Kamh for the second season. During the last week of September, the population density of different aphid's species was obviously reduced on maize plants in various districts under study. We can use these results in IPM program for controlling aphids on Maize.