Opisina arenosella has been an outbreak pest of coconut trees in southern China since 2013. To develop efficient control methods for this invasive pest, adequate rearing protocols are desirable. In this study, an orth...Opisina arenosella has been an outbreak pest of coconut trees in southern China since 2013. To develop efficient control methods for this invasive pest, adequate rearing protocols are desirable. In this study, an orthogonal array of artificial diets with 11 factors at 3 levels was deployed for both 2 nd–4 th and 5 th–6 th instar larvae of O. arenosella. Biological parameters including survival time of larvae, development time from larva to pupa, pupation rate, emergence rate, and pupal weight were monitored to reveal the most important components in the diet formulas. Biological parameters in O. arenosella were most affected by brewer’s yeast, sucrose, ascorbic acid, and wheat germ. Statistical analysis indicated that different diet combinations supported optimum performance of biological parameters for 2 nd–4 th and 5 th–6 th instar larvae. The validity of the optimization predicted by the orthogonal array analysis was confirmed in a follow-up bioassay with similar optimized diets for both 2 nd–4 th and 5 th–6 th instar larvae. The optimal artificial diet has great potential for the mass rearing technique, and can provide valuable results for using parasitoids in biological control of O. arenosella.展开更多
Ecological networks,usually depicting interactions among species,have been recently down-scaled to the individual level,permitting description of patterns of inter-individual resource variation that are usually hinder...Ecological networks,usually depicting interactions among species,have been recently down-scaled to the individual level,permitting description of patterns of inter-individual resource variation that are usually hindered at the species level.Optimal diet theory(ODT)models,applied to prey–predator systems,predict different patterns of nestedness and modularity in the network,depending on the available resources and intra-specific competition.The effect of resource availability on the emergence of networks structures,and ODT framework,has not yet fully been clarified.Here,we analyzed the structural patterns of individual-resource networks in 3 species of Mediterranean salamanders,in relation to changes in prey availability.We used weighted individual-resource network metrics to interpret the observed patterns,according to 3 ODT models.We found significant nestedness recurring in our study system,indicating that both selective and opportunistic individuals occur in the same population.Prey diversity,rather than abundance,was apparently related to inter-individual resource variation and promoted the emergence of significant modularity within all networks.The observed patterns of nestedness and modularity,together with the variation in resource diversity and intra-specific competition,are in agreement with the distinct preferences model of ODT.These findings suggest that in the focal prey–predator systems,individuals were able to perceive changes in prey diversity and to exploit in different ways the variations in composition of available resources,shifting their diet assembly rules accordingly.Our findings also confirm that the use of weighted individual-resource networks,in prey–predator systems,allows to disclose dynamics that are masked at the species or population level.展开更多
基金supported by the National Key Research and Development Program of China (2016YFC1201200)the National Key Technologies R&D Program of China during the 12th Five-Year Plan period (2015BAD08B03)the Central Public-interest Scientific Institution Basic ResearchFund for Chinese Academy of Tropical Agricultural Sciences (1630042017013 and 1630042017012)
文摘Opisina arenosella has been an outbreak pest of coconut trees in southern China since 2013. To develop efficient control methods for this invasive pest, adequate rearing protocols are desirable. In this study, an orthogonal array of artificial diets with 11 factors at 3 levels was deployed for both 2 nd–4 th and 5 th–6 th instar larvae of O. arenosella. Biological parameters including survival time of larvae, development time from larva to pupa, pupation rate, emergence rate, and pupal weight were monitored to reveal the most important components in the diet formulas. Biological parameters in O. arenosella were most affected by brewer’s yeast, sucrose, ascorbic acid, and wheat germ. Statistical analysis indicated that different diet combinations supported optimum performance of biological parameters for 2 nd–4 th and 5 th–6 th instar larvae. The validity of the optimization predicted by the orthogonal array analysis was confirmed in a follow-up bioassay with similar optimized diets for both 2 nd–4 th and 5 th–6 th instar larvae. The optimal artificial diet has great potential for the mass rearing technique, and can provide valuable results for using parasitoids in biological control of O. arenosella.
基金by the Italian Ministry of Environment(DPN–2008–0008213 and PNM–II–2012–0015691)by the Prefecture of Haute Corse,France(2B–2018–01–92–004).
文摘Ecological networks,usually depicting interactions among species,have been recently down-scaled to the individual level,permitting description of patterns of inter-individual resource variation that are usually hindered at the species level.Optimal diet theory(ODT)models,applied to prey–predator systems,predict different patterns of nestedness and modularity in the network,depending on the available resources and intra-specific competition.The effect of resource availability on the emergence of networks structures,and ODT framework,has not yet fully been clarified.Here,we analyzed the structural patterns of individual-resource networks in 3 species of Mediterranean salamanders,in relation to changes in prey availability.We used weighted individual-resource network metrics to interpret the observed patterns,according to 3 ODT models.We found significant nestedness recurring in our study system,indicating that both selective and opportunistic individuals occur in the same population.Prey diversity,rather than abundance,was apparently related to inter-individual resource variation and promoted the emergence of significant modularity within all networks.The observed patterns of nestedness and modularity,together with the variation in resource diversity and intra-specific competition,are in agreement with the distinct preferences model of ODT.These findings suggest that in the focal prey–predator systems,individuals were able to perceive changes in prey diversity and to exploit in different ways the variations in composition of available resources,shifting their diet assembly rules accordingly.Our findings also confirm that the use of weighted individual-resource networks,in prey–predator systems,allows to disclose dynamics that are masked at the species or population level.