The Asymmetrical Performance Of Non-host Food Addition On The Adults Of Liriomyza Trifolii Versus Two Parasitoid Species

In the plants,herbivores and natural enemies third-level nutrition interaction,the adult stage of herbivores and parasitic natural enemies often needs to be supplemented with non-host foods(such as pollen,nectar,honeydew,etc.),but different herbivores or different parasitoids differ in the degree and manner of supplementation of non-host food requirements.This is mainly influenced by the mode of nutrient acquisition of the herbivores and parasitic wasps,as well as the corresponding differences in egg production and maturation mechanisms.For example,adults of some herbivorous insect pests do not feed on host plants,while some adult insect pests require feeding of host;some adult parasitic insects only have the pest-controlling characteristics of parasitic hosts,while some adult parasitic insects have feeding habits.It is generally believed that supplementation with non-host foods can promote the longevity and fertility of herbivorous and parasitic natural enemies.For many years,supplementing non-host food in the field(such as spraying honey water or sugar substances or planting nectar plants,etc.)has often been used as an ecological control method to improve the control effect of natural enemies.However,the synergy effect is often inconsistent,and few studies have considered supplements non-host foods whether is asymmetry synergistic effects between herbivorous and natural enemies,and what is the law of asymmetry?Among the herbivorous insects belonging to the Agromyzidae,many kinds of leafminers are important pests that endanger vegetables,flowers,and other economic crops,and the species of parasitic wasps of Liriomyza sativae is abundant.China is one of the most severely countries affected of Agromyzid leaf miner.Especially the invasion and spread of Liriomyza sativae(Blanchard)and Liriomyza trifolii(Burgess)exacerbated the hazard situation.Parasitic wasps plays an important regulatory role.The leafminers are all strong synovigenic insects.Adults not only feed on the leaves of host plants,but also need to supplement non-host foods.Most of the parasitoids of leaf miners are synovigenic parasitoid.Not only has the parasitic characteristics of spawning parasitism,but also has the pest-controlling characteristics of host feeding to obtain nutrition,and the parasitoids can also feed on non-host foods,but the feeding and controlling characteristics of different parasitoids are different.In this study,Liriomyza trifolii(Burgess)and its two dominant natural enemies Hemiptarsenus varicornis(Girault)and Opius caricivorae(Fischer)are used as examples.Comparison of the effects of non-host foods on the characteristics of life history of leafminers and their parasitoids,and further analysis of their physiological indicators,in order to illustrate the asymmetry of non-host food supplementation for herbivorous pests and parasitic natural enemies.The results provides theoretical basis and practical guidance for the field application and ecological regulation of parasitic wasps.The feeding characteristics and control characteristics of different parasitoids are also different.Supplementing non-host foods has different effects on the potential for controlling pests of L.trifolii and different species of parasitoids.L.trifolii and parasitic wasps cause asymmetrical biased results.The main findings and conclusions are as follows:1.Effect of supplementation of non-host foods on characteristics of adults' life history parameters of L.trifolii and its parasitic waspsSupplemental non-host foods significantly increased the proliferative potential of L.trifolii,which was mainly reflected in the significant increase in survival of L.trifolii during nutritional supplementation.Longevity of females was 2.66 times longer than supplemental the host,and the fecundity and daily fecundity were 3.84 times and 1.57 times.Supplemental non-host foods has different effects on the proliferation potential of different species of parasitoids.There was no significant effect on the proliferative potential of H.varicornis,but the proliferative potential of O.caricivorae was significantly increased.When supplemented with non-host foods,the longevity,host-parasitilizing events,host-feeding events,and host mortality dose of the H.varicornis females increased slightly,but they were not significant.Both the daily host-parasitilizing events,daily host-feeding events,and daily host mortality of females dose decreased,and the results were not significant either.When supplemented with non-host foods,the longevity of the female O.caricivorae was 9.78 times that of the host.The host-parasitilizing events,host-feeding events,and host mortality dose were 17.81 times,6.86 times and 11.10 times than supplemental the host,respectively;and the daily host-parasitilizing events and daily host mortality of females significantly increased,and the daily host-feeding events was significant reduce.Supplemental non-host foods had different effects on the proliferative potential of L.trifolii and two parasitic wasps.The proliferative potential of L.trifolii and O.caricivorae was increased when supplemented with non-host foods,but the potential for controlling damage was even greater for O.caricivorae.There was no significant effect on the H.varicornis.2.Effects of supplementation of non-host foods on physiological indices of nutrient accumulation and utilization of L.trifolii and its parasitic waspsSupplemental non-host foods significantly increased the total sugar content in L.trifolii,and the glycogen content and lipid content were higher than those of the host only.Supplemental non-host foods had different effects on the physiological indicators of different species of parasitoids.Supplementation of non-host foods significantly increased the total sugar content of O.caricivorae,but it was not significant for H.varicornis.The glycogen content and lipid content in the O.caricivorae was higher compared with the host only when supplemented with non-host foods,while the H.varicornis was lower.Nutrition utilization of L.trifolii and two parasitoids are different when non-host foods supplements.The ability of L.trifolii and O.caricivorae to absorb and transform non-host foods was stronger,which was in agreement with the results of supplemental nutrition significantly extend their longevity and increases fecundity.3.Research results and significanceBased on the proliferative potential and changes in physiological indices of L.trifolii,H.varicornis,and O.caricivorae,the results of this study showed that the degree of dependence of Liriomyza-parasitoids on non-host food was different,and analyze the relationship between its behavioral changes and the accumulation of nutrients.The research results theoretically reveal that there is asymmetry in supplementation of non-host foods for herbivores and natural enemies,and provide theoretical guidance for the rational use of parasitic wasps in practice.