Abstract
Potato tubers were irradiated with different doses of gamma irradiation (50,100 and 200Gy), and fed by the larvae of Phthorimaea operculella (Lepidoptera : Gelechiidae), to measure the effect of larval feeding on some biochemical components of the adult stage. The data indicated that the change in larval diet (tubers) due to irradiation led to some changes in such biochemical components of the adult. Irradiation increased phenolic content and oxidation capacity of potato tubers, while vitamin C was significantly reduced. Vitamin C content of the adult was not significantly changed at most doses. From the nutritional point of view, this means that the decrease in a nutrient in the diet not necessitate corresponding suppression in the feed insects. Acid and alkaline phosomonoesterases activities and trehalose content of the adult were significantly depressed. Such depression was related to the increased phenolic content of potato tubers after irradiation. This provides an evidence that irradiation of potato tubers could leads to products which might be toxic to insects and able to change in the diet (tubers) component that fed by the larvae. It is interesting to realize that ionizing irradiation inactivate pathogens or directly killed store insect stages, but also could control reinfestation of pest by producing changes in nutrients of potato tubers, and increasing toxic compounds, resulting in abnormalities which could extent to the adult stage and reduce its reproductive capacity.
Highlights
Larvae are actively feeding stage of holometabolic phytophagous insects; they are able to select the diet that will provide the best development
Table (1) shows the effect of larval feeding on irradiated potato tubers on Ph. operculella adults acid and alkaline phosphomonoesterases (Alkpase and Acpase)
The results obtained indicated that the change of larval diet due to irradiation led to some macromolecular abnormalities in the adult stage
Summary
Larvae are actively feeding stage of holometabolic phytophagous insects; they are able to select the diet that will provide the best development. Nutritive value of food and the presence of secondary plant metabolites or allelochemicals in host plants determine performance of phytophagous larvae (Mattson and scriber, 1987), titer of detoxification enzymes (Lindroth et al, 1991 and Amin, 2007), and even reproduction of adults (Fernandes-Da-Silva and Zucoloto, 1997). The potato tuber moth (PTM), Phthorimaea operculella Zeller (Lepidoptera: Gelechiidae) is a major pest of potatoes worldwide (Fenemor,e 1988). Potato tubers are the most vulnerable to infestation with such pest. Conventional control methods are not very successful because the larvae pass a major portion of their life inside the tubers (Haiba, 1990). E.g. gamma rays, X-rays or electrons, can be used to extend the life of certain fruits and vegetables by delaying ripening or killing
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Egyptian Academic Journal of Biological Sciences. A, Entomology
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
