【摘 要】
：
Diapause is an adaptation that insects have evolved to synchronize their life cycle with that of seasonal climatic changes and resources availability.However,cues for its induction are not always clear and,in some cases,a maternal effect may be involved.A
【机 构】
：
Department of Entomology,University College of Agriculture,University of Sargodha,Sargodha,Pakistan;
论文部分内容阅读
Diapause is an adaptation that insects have evolved to synchronize their life cycle with that of seasonal climatic changes and resources availability.However,cues for its induction are not always clear and,in some cases,a maternal effect may be involved.At the population level,just a part of the individuals may exhibit diapause with important consequences in terms of winter survival.Moreover,clear indicators of diapause state are difficult to identify.Diapause induction was thus investigated in the aphid parasitoid species Aphidius ervi Haliday(Hymenoptera:Braconidae)developing in the aphid Sitobion avenae(Hemiptera:Aphididae)at four crossed photothermal regimes(16℃and 8℃,16:8 h L:D and 8:16 h L:D),and during 2 successive generations.We analyzed the reliability of changes in mummy color to assess for the diapausing state compared to dissections,and we measured parasitoid morphological and physiological traits.We observed that the proportion of dark brown mummies increased after one generation under low photothermal regime compared to other regimes.No diapause was recorded at 16℃,16:8 h L:D,while we observed 16.2％and 67.5％diapause incidence at 8℃,8:16 h L:D,at 1st and 2nd generation,respectively.Diapause induction is thus increased by short day-length conditions and low temperatures as well as by maternal effects.All parasitoid life-history traits(weight,size,fat content,water content,egg-load,and longevity)were affected by the photothermal regime and/or the generation.These results raise new questions on the environmental thresholds needed to induce diapause and on survival and adaptation potential of commercially available parasitoid strains in different environments.
其他文献
The insect group Ⅱ chitinase(ChtⅡ,also known as Cht10)is a unique chitinase with multiple catalytic and chitin-binding domains.It has been proven genetically to be an essential chitinase for molting.However,ChtⅡ\'s role in chitin degradation during inse
In most eusocial insects,the division of labor results in relatively few individu-als foraging for the entire colony.Thus,the survival of the colony depends on its efficiency in meeting the nutritional needs of all its members.Here,we characterize the net
The fall armyworm(FAW),Spodoptera frugiperda,is a major pest native to the Americas that has recently invaded the Old World.Point mutations in the target-site proteins acetylcholinesterase-1(ace-1),voltage-gated sodium channel(VGSC)and ryan-odine receptor
The pea leafminer,Liriomyza huidobrensis,is an important pest species af-fecting ornamental crops worldwide.Plant damage consists of oviposition and feeding punctures created by female adult flies as well as larva-bored mines in leaf mesophyll tissues.How
Spodoptera frugiperda(Lepidoptera:Noctuidae)is a widely distributed pest of corn.Since it invaded China in 2018,it has caused serious damage to local corn produc-tion.Chlorantraniliprole,an anthranilic diamide insecticide,has been widely used to con-trol
Wings are an important flight organ of insects and their morphogenesis de-pends on a series of cell-to-cell and cell-to-extracellular matrix interactions.Integrin as a transmembrane protein receptor mediates cell-to-cell adhesion,cell-to-extracellular ma-
Recent studies demonstrated that the Painted Lady(Vanessa cardui),a cos-mopolitan diurnal butterfly performs long-range migration between subtropical Africa and north-western Europe,covered by individuals belonging to up to six generations.Here we analyze
Lepidopteran insects produce cocoons with unique properties.The cocoons are made of silk produced in the larval tissue silk gland and our understanding of the silk genes is still very limited.Here,we investigated silk genes in the bagworm moth Eumeta vari
The evolutionary success of phytophagous insects depends on their ability to efficiently exploit plants as a source of energy for survival.Herbivorous insects largely depend on the efficiency,flexibility,and diversity of their digestive physiology and so-
Species range expansions are crucial for understanding niche formation and the interaction with the environment.Here,we studied the bumblebee Bombus haematu-rus Kriechbaumer,1870,a species historically distributed from northern Serbia through northern Ira