Food deprivation effects on carbohydrate levels and their relation to feeding responses of western cherry fruit fly Rhagoletis indifferens to spinosad bait

• Published in: Physiological entomology 2009-06, Vol.34 (2), p.163-173
• Main Authors: YEE, WEE L, CHAPMAN, PETER S
• Format: Article
• Language: English
• Subjects: Behavioural responses; Diptera; metabolism; Prunus; Rhagoletis indifferens; starvation; sugar; sugars; Tephritidae
• ISSN: 0307-6962; 1365-3032
• DOI: 10.1111/j.1365-3032.2009.00670.x

The nutritional state of tephritid fruit flies affects various behaviours. The present study aims to determine food deprivation effects on carbohydrate levels and their relation to feeding responses to spinosad bait (GF-120® Naturalyte® Fruit Fly Bait; Dow AgroSciences, Indianapolis, Indiana), as measured indirectly by mortality, in western cherry fruit fly Rhagoletis indifferens Curran (Diptera: Tephritidae). Sugar levels in 1-2-day-old flies exposed to sugar for 1 h and then deprived of sugar for 10-24 h decrease but, in flies with access to continuous sugar and no sugar, they increase and do not change, respectively. Sugar levels in 14-15-day-old flies that have had free access to yeast extract and sugar and are then deprived of it for 0 and 10 h do not differ but they are lower at 24 and 30 h. Mortalities of 1-2-day-old flies exposed to sugar for 1 h and then deprived of it for 0-24 h progressively increase but they do not increase in flies given no sugar because the mortalities in this treatment are equally high at all times. By contrast, mortalities of 14-15-day-old flies deprived of food increase from 0 to 10-30 h but there are no differences from 10 to 30 h. Mortalities of 14-15-day-old flies deprived of food for 3 and 6 h also do not differ. Food deprivation effects on glycogen are similar, although glycogen occurs at lower levels than sugar. The results obtained suggest that R. indifferens flies need to feed multiple times on carbohydrate foods during the day to maintain their carbohydrate levels, that their responses to spinosad bait will increase if they do not, and that there may be age-related effects on carbohydrate levels and responses to spinosad bait.