Population fluctuations of cereal aphids, Rhopalosiphum padi (L.) and Sitobion avenae (F.) (Homoptera: Aphididae) and their impact on crop loss parameters of wheat Population fluctuations of cereal aphids, Rhopalosiphum padi (L.) and Sitobion avenae (F.), (Homoptera: Aphididae) and their impact on crop loss parameters of wheat were revealed in Antakya during the years of 1998–2002. The aphid populations were recorded in infested and aphid-free plots in Reyhanlı by seven day intervals from 22 February to 22 April, 1999 on two wheat varieties, “Genç-99” and “Ege-88”. Twenty plants were examined at each sampling date and alive induviduals (adult+nymph) were counted. Mean plant height, spike length (cm), number of maximum stems, number of spikes, number of spikelets pers pike, number of grain per spike were not effected, while hectoliter weight, spike yield, and grain yield (except “Ege-88”) were differed between the infested and aphid-free plots, significantly. The population densities were higher and occured in early stages in the growing seasons of 1998–1999 than those of 2000 to 2002. Predatory insects, Coccinella septempunctata (L.), C. undecimpunctata L., Synharmonia conglobata (L.), Adonia variegata (Goeze), Episyrphus balteatus (DeGeer), Metasyrphus corollae (F.), Melanostoma mellinum (L.), Meliscaeva auricollis (Meigeu), Sphaerophoria scripta (L.), Chrysoperla carnea (Stephens) and parasitoid, Aphidius uzbektanicus Luthetzki and entomopathogenic fungi, Metarhizium sp. were found to be as natural enemies of the cereal aphids. Further studies are needed on economic threshold levels of cereal aphids and the reactions of different wheat varieties to minimize the crop loss and avoid the unnecessary control measures. Furthermore, meteorological conditions and population densities of the natural enemies throughout the growing season should be considered before deciding on pest status of cereal aphids
Primary Language | Turkish |
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Journal Section | Articles |
Authors | |
Publication Date | February 1, 2007 |
Submission Date | February 8, 2014 |
Published in Issue | Year 2007 Volume: 31 Issue: 1 |