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The giant water bug Appasus major exhibits a peculiar reproductive behavior where females lay eggs on the backs of males. A male and female pair performs frequent repeat copulations during the oviposition behavior, and the male carries the deposited eggs until hatching. Such characteristic behaviors predict that the eggs are fertilized by the brooding males. If males carry eggs of other unrelated males, the egg carrying will drastically decrease the fitness of the carriers. In this study, we examined genetic relationships between the 489 eggs and nine males carrying them collected from the field, using microsatellite DNA markers. We revealed that in total, 28.4% of the eggs were of other male origin. This is the first report of frequent brood parasitism in an aquatic egg‐carrying hemipteran insect. The brood parasitism is adaptive for the females probably because it enables them to increase the chance of oviposition, or it can equalize motility risk of the eggs of each mate. 相似文献
84.
Margaret Louise Allen 《Entomologia Experimentalis et Applicata》2011,138(2):83-92
In recent years, RNA interference (RNAi) has been validated as a viable approach for functional genetic studies in non‐model organisms. In this report we demonstrate the efficacy of RNAi in the tarnished plant bug, Lygus lineolaris (Palisot de Beauvois) (Miridae: Hemiptera). A L. lineolaris inhibitor of apoptosis gene (LlIAP) has been identified and cloned. The translated sequence encodes a 381 amino acid protein similar to other insect IAPs and contains two conserved baculovirus inhibitor of apoptosis protein repeat (BIR) domains. Microinjection of double stranded RNA (dsRNA) corresponding to two disparate portions of the gene resulted in decreased LlIAP mRNA quantities relative to controls. Both nymphs and adult specimens injected with IAP dsRNA exhibited significantly reduced lifespan compared with those injected with non‐insect dsRNA (eGFP). Thus, RNAi‐mediated knockdown of LlIAP expression has been correlated with a lethal phenotype in adults and nymphs. 相似文献
85.
The attractiveness of 22 synthetic volatile blends or seven individual chemicals emitted from flowering rice panicles to a rice leaf bug, Trigonotylus caelestialium (Kirkaldy), were investigated with an olfactometer to identify the active compounds responsible for the invasion of the bugs into paddy fields. n‐Decanal attracted only male bugs, whereas β‐caryophyllene attracted only females. β‐Elemene repelled males and methyl benzoate marginally repelled females. The other chemicals did not attract or repel male and female bugs at all. Two‐, 3‐, 4‐ and 5‐component blends of β‐caryophyllene, n‐decanal, n‐tridecene, methyl salicylate and geranyl acetone were attractive to neither females nor males. Two‐component blends comprised of β‐caryophyllene and methyl salicylate, or n‐decanal and methyl salicylate, marginally repelled females. The three‐component blend comprised of β‐caryophyllene, n‐decanal and geranyl acetone marginally repelled females. The five‐component blend comprised of β‐caryophyllene, n‐decanal, n‐tridecene, methyl salicylate and geranyl acetone repelled males. The seven‐component blend comprised of β‐caryophyllene, n‐decanal, n‐tridecene, methyl salicylate, geranyl acetone, methyl benzoate and β‐elemene attracted female bugs and marginally attracted male bugs. Six‐component blends without any one of these seven components were not attractive to the bugs although the six‐component blend without n‐decanal was marginally attractive to females. The six‐component blend without n‐tridecene repelled males. These findings suggest that mixtures of these seven compounds play an important role in the attractiveness of flowering rice panicles to both sexes of the bugs, although the attractiveness of individual compounds differs between sexes. 相似文献
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87.
The adaptation to light of compound eyes in insects has been extensively documented and their adaptive role is well understood. Much less attention has been paid, however, to the control of ocelli sensitivity, a study which could help us to understand the functional role of these simple eyes. We analyzed the dynamic changes in the distribution of screening pigments which occur in the ocelli of the haematophagous bug, Triatoma infestans, when the insects are subjected either to light/dark cycles (LD), to constant darkness (DD) or constant light (LL). We then compared these changes with those occurring in the compound eyes of the same individuals and found that, while compound eyes are subject to the control of an endogenous circadian clock, the adaptation of the ocelli is entirely dependent on environmental illumination. In addition, we have observed that environmental temperature is not involved in the control of screening pigments in either ocelli or compound eyes as a direct stimulus, nor as a Zeitgeber. The existence of a differential control in the components of the dual visual system represents an adaptive advantage in the adjustment of visual sensitivity in insects exposed to quick changes in lighting conditions in their natural habitat. We discuss the implications of our findings with regards to the biology of triatomines and with respect to the general understanding the functional role of insect ocelli. 相似文献
88.
The sycamore lace bug, Corythucha ciliata is a new, invasive pest of Platanus trees in China. Although C. ciliata is often subjected to acute low temperatures in early winter and spring in northern and eastern China, the cold tolerance of C. ciliata has not been well studied. The objectives of this study were to determine whether adults of C. ciliata are capable of rapid cold hardening (RCH), and to compare the benefits of RCH vs. cold acclimation (ACC) in the laboratory. When the adult females incubated at 26 °C were transferred directly to the discriminating temperature (−12 °C) for 2 h, survival was only 22%. However, exposure to 0 °C for 4 h before transfer to −12 °C for 2 h induced RCH, i.e., increased survival to 68%. RCH could also be induced by gradual cooling of the insects at rates between 0.1 and 0.25 °C min−1. The protection against cold shock obtained through RCH at 0 °C for 4 h was lost within 1 h if the adults were returned to 26 °C before exposure to −12 °C. Survival at both −12 and −5 °C was greater for RCH-treated than for ACC-treated adults (for ACC, adults were kept at 15 °C for 5 days), and the lethal temperature (2 h exposure) was lower for RCH-treated than for ACC-treated adults. The results suggest that RCH may help C. ciliata survive the acute low temperatures that often occur in early winter and early spring in northern and eastern China. 相似文献
90.
Tamara Szentivnyi Sndor Hornok ron B. Kovcs Nra Takcs Mikls Gyuranecz Wanda Markotter Philippe Christe Olivier Glaizot 《Ecology and evolution》2022,12(10)
Polyctenidae bugs are rarely studied, hematophagous, and highly specialized ectoparasites of bats. There are only 32 described species worldwide, including six species in the Afrotropical region. Knowledge on these parasites is limited, and most studies are restricted to the New World polyctenid species. Here we report additional records of Adroctenes horvathi from Kenya and South Africa, as well as Hypoctenes faini from Rwanda. We present an updated list of published polyctenid records in the Afrotropical region indicating their host specificity and their geographical distribution. We report global infection patterns and sex ratio of polyctenids based on previously published data, including Old and New World species. Lastly, we demonstrate the first molecular phylogeny of Polyctenidae, showing their phylogenetic relationship with the closely related family Cimicidae. 相似文献