Photoperiodic, thermal and trophic responses of a predatory ladybird Cheilomenes propinqua

Abstract

Diapause which enhances survival during unfavourable periods is one of the most common seasonal adaptations of insects. A typical 'diapause syndrome' includes an arrest of development (or of reproduction is the case of adult diapause), a decrease in metabolism, an increase in the resistance to adverse environmental conditions, an accumulation of reserves, etc. In contrast to quiescence, facultative diapause is an 'anticipatory response', that is it is induced by environmental cues before the beginning of the adverse sea

Storage Potential of the Predatory Ladybird Cheilomenes propinqua in Relation to Temperature, Humidity, and Factitious Food

“…These ranges of temperatures were used because we presumed that the storage temperature at the rearing facility can be strictly controlled, whereas the transportation conditions can vary considerably. Regarding the long-term experiment, our (unpublished) pilot test demonstrated that at temperatures of 10 °C and lower C. propinqua adults are not able to feed, whereas the results of our previous study [ 28 ] suggest that feeding on some factitious food is necessary for their long-term storage. On the other hand, another earlier study [ 30 ] showed that at 20 °C (in contrast to 15 °C) C. propinqua females matured and laid eggs, suggesting that the temperature of 20 °C is too high for long-term storage.…”

“…To start the experiment, a cohort of the first instar larvae hatched over 24 h from eggs laid by 10–20 C. propinqua females was reared on the green peach aphid at a temperature of 25 °C and L:D = 10:14, i.e., under the short-day conditions that increase the survival of starving females [ 28 ]. The emerging adults were kept in groups of 20–50 individuals under the same conditions for 5 more days.…”

“…However, we consider C. propinqua as a potential mass-reared agent for the biological control of greenhouse pests. In this context, it should be noted that—under the optimal conditions—this relatively small (body length 4–5 mm) and rapidly developing (10–11 days from egg to adult stage) ladybird shows rather high voracity (females consumed 40–80 aphids per day, depending on the prey species; when feeding on A. gossypii , larvae consumed a total average of about 500, and females consumed about 2000 individuals) and fecundity (15–30 eggs per day, with a total lifetime fecundity of about 1000 eggs per female) [ 21 , 28 , 29 , 30 ]. Such a combination of beneficial properties suggests that C. propinqua , as well as some other coccinellids [ 31 ], can be an effective agent for biological control.…”

“…The use of an insect predator for the biological control of pests of protected crops, as was noted above, involves the development of optimal methods for its mass rearing, storage, packaging, distribution, and release, which in turn requires a basic knowledge of its ecophysiology. The influence of the temperature and prey species on the rate of development, fecundity, mortality, net reproductive rate, and some other biological parameters of C. propinqua has been investigated [ 11 , 20 , 28 , 30 ]. The storage potential, however, was not studied.…”

Signal and Nutritional Effects of Mixed Diets on Reproduction of a Predatory Ladybird, Cheilomenes propinqua

“…Moreover, feeding some coccinellids on alternative or low-quality essential food results not only in the delay or termination of oogenesis but also in the decrease of metabolism, the accumulation of fat, and other components of the adult (reproductive) diapause. This so-called 'trophic diapause' has been demonstrated not only in predatory [13][14][15][16][17][18][19][20] but also in phytophagous ladybirds [21,22]. Thus, food can have a double impact on the reproduction of coccinellids: (1) 'signal' effect (as an environmental diapause-inducing or diapause-averting cue) and ( 2) 'nutritional' effect (specific nutrients are necessary for oogenesis).…”