![]() ![]() septempunctata was significantly affected by Imidacloprid and Clothianidin. The statistical analysis showed that non-significant differences were recorded at lower concentrations of both pesticides. ![]() ![]() Whereas the adult beetles demonstrated highest mortality (75 % and 62.5 %) when exposed to Imidacloprid (0.7%) after 48 and 24 h of exposure, respectively. The adult beetles showed highest mortality (100 % and 50 %) when subjected to Clothianidin (0.7%) after 48 and 24 h of exposure, respectively. septempunctata were observed amongst control and other treatments. The significant differences in the mortality of C. The effect of Imidacloprid and Clothianidin (Telsta) on predation of adult beetles predating on rose aphid, Macrosiphum rosae was evaluated under laboratory conditions (25 ± 2 ✬ and 65 ± 5 % RH) at Systematics and Pest Management Laboratory, Department of Zoology University of Gujrat. Mostly pests are managed by the use of pesticides in crops and ornamentals, thus, impact of pesticides needs to be evaluated on predatory efficacy of predatory beetle. All rights reservedĬoccinella septempunctata is an important natural enemy of several pest species attacking various crops in Pakistan. axyridis adults are less affected than larvae by the frequent use of the defensive secretions in their stressful habitats. The strength of maternal and paternal effects on progeny development of parents bled at the larval stage were higher in earlier clutches. As the underlying effects of bleeding on females’ offspring in the early clutches were diminished in the late ones, suggesting another transgenerational effect. Males that suffered bleeding during their larval stage accelerated progeny development of non‐bled females in early clutches, suggesting a positive transgenerational effect of larval bleeding, while males that did not suffer bleeding accelerated progeny development of bled females in later clutches. Offspring crosses that included a parent bled during the larval stage suffered fitness costs in development and female body mass, while those bled during the adult stage suffered no transgenerational costs. Egg fertility was reduced for crosses where either one or both parents had been bled during the larval or adult stage. Beetles bled during their larval stage spent a longer time in development and weighed less than controls. We examined the costs of reflex bleeding in larval and adult stages of the ladybird beetle Harmonia axyridis on offspring fitness and reproductive performance through the comparisons between bled and control larvae, reciprocal crosses of bled/control beetles, and early and late clutch phenotypes. Reflex bleeding is an important antipredator defense mechanism in Coccinellidae. ![]() Overall, our results indicate that repeated reflex bleeding weakens a ladybird’s immune system and can increase their susceptibility to pathogens, but a ladybird’s reproductive potential remains almost unaffected, even by very intensive reflex bleeding. Moreover, ladybirds bleeding larger amounts of haemolymph started their reproduction significantly later. Daily reflex bleeding did not result in decreased fecundity of young ladybirds during the first 30 days of their adult life, but the start of ladybird reproduction was delayed by about two days. Interestingly, resource limitation in the form of complete food absence did not significantly interact with reflex bleeding, even though starvation itself had a strong negative effect on all haemolymph parameters investigated and individual body mass. Repeated reflex bleeding did not result in significant body mass reduction. Reflex bleeding induced twice a week for three weeks resulted in a significant reduction in haemocyte concentration, total protein content, and antimicrobial activity against Micrococcus luteus, and a marginally non-significant decrease in antimicrobial activity against Escherichia coli. In this study, we examined the immune and fitness costs of repeated reflex bleeding in adults of the invasive ladybird Harmonia axyridis, investigating several haemolymph parameters. Interestingly, this issue has rarely been investigated for adult insects. At the same time, significant costs of reflex bleeding can be expected because bled haemolymph is lost and all valuable components included have to be renewed. In insects, external chemical defences, such as reflex bleeding, have been proved to be an efficient strategy against various predators. ![]()
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