الفهرس | Only 14 pages are availabe for public view |
Abstract The Egyptian cotton leafworm, Spodoptera littoralis (Lepidoptera: Noctuidae), is the most destructive pest. It is a good model insect to study the biochemical changes during the progress of age and the neurophysiological basis of odour-mediated behaviour. The present work aims to understanding the effect of age factor on some biochemical parameters of different organs such as antenna, fat body and gonads of the cotton pest S. littoralis adults under the effect of two different host plants; castor oil and mulberry leaves. Also, is there a relationship between biochemical changes, especially protein of antennae and of the other mentioned body organs during development of adult moths? Our results showed that there were changes in internal reproductive system morphology of both sexes especially at S2 and there was a variation in the amounts of egg deposited under the effect of castor oil and mulberry leaves. In addition, significant changes were observed in consumption of total proteins, carbohydrates, lipids and trehalose concentrations and the ACP and ALP activities in different organs of both adults during life span. In antenna, mRNA expression levels of SlCXE7 and SlDGK were altered also, antennal dopamine concentration was changed under the impact of different plant odours. In SDS-PAGE protein profile, we could identify lipoprotein (Lp), hexamerin (Hex), vitellogenin (Vg), carboxylesterase (CXE) and odorant binding protein (OBP). Our study provided evidence that age was a factor significantly affecting the sensitivity of S. littoralis towards the widely odours. Interestingly; castor oil plant is a preferable host plant and mulberry plant is a non-preferable host plant for S. littoralis adults. In addition, plant odorants had an effect on the postponement of insect physiology and behaviour. Moreover, mulberry volatiles negatively affected calling, mating and egg deposition behaviours. More attention is needed to understand the chemical interaction between plant volatiles in the surrounding environment and the different insects to use it in pest control programs. |