Biological Characteristics Of Anisopteromalus Calandrae (Howard) And Its Potential For Control Of Lasioderma Serricorne (Fabricius)

Anisopteromalus calandrae（Howard）belongs to Anisopteromalus（Hymenoptera:Pteromalidae）.It has the advantages of short developmental duration,high fertility and strong search ability.It is a parasitic natural enemy with great development potential.In the investigation of the parasitic wasp of Lasioderma serricorne,the A.calandrae was the dominant parasitic wasp of L.serricorne.In this paper,the biological characteristics of A.calandrae were studied,and the developmental threshold temperature and effective accumulated temperature of A.calandrae were determined.The effects of different hosts on the growth,development and reproduction of A.calandrae were compared.The control potential of A.calandrae against L.serricorne was evaluated.It can provide a favorable reference for controlling beetle storage pests,and lay a foundation for further investigation of the parasitic mechanism of A.calandrae.1.Investigation and identification of the parasitoids of L.serricorneThe parasitic wasp species of the L.serricorne was investigated by indoor trapping method,and the antennae of the dominant parasitic wasp——A.calandrae were observed by scanning electron microscopy.The investigation found that there is only one species of parasitic wasp in L.serricorne in Guiyang——A.calandrae.A.calandrae has a filamentous shape,which is born in the middle of the face of the head.It consists of the stalk,the stalk and the whip（ring,knot,rod）,coat,13 knots.2.Biological characteristics of A.calandrae,parasitized on L.serricorneThe biological characteristics of the parasitic wasp A.calandrae of L.serricorne were studied by indoor feeding experiments,including observation of the developmental state,developmental duration,emergence,mating and spawning of A.calandrae under anatomical microscope,and observation of supplemental nutrition（10%honey solution）effects on the life and reproduction of A.calandrae adults.Studies have shown that the A.calandrae mainly parasitizes the old larvae and pupa of L.serricorne and overwinters in mature larvae or pupa in the host cocoon.At 25℃,70%RH,photoperiod 16L:8D,the developmental durations of each stage were as follows:egg,1.5 d;larva,5.9 d;pupa,9.9 d;pre-oviposition,0.9 d;and adult,15.1 d.It needs 18.2 d to complete a generation.Number of offspring per female A.calandrae was 29 to 82,averaging 54.75 in the laboratory.At 25℃,fed with 10%honey solution,the females lived 29.6 d and produced 76.1 offsprings.With short developmental period,high fecundity,and active search ability,A.calandrae is of a great potential for application as biocontrol agent.3.Influence of temperature on the development and reproduction of A.calandraeThis study aims to explore the influence of temperature on the development and reproduction of the experimental populations of A.calandrae.The duration of different developmental stages of A.calandrae were measured at 5 different temperatures,and the developmental threshold temperature and effective accumulated temperature were calculated by using least square method,the relationship between temperature and developmental stage was fitted using line regression,Logistic model and―Wang-Lan-Ding‖model.The results revealed that the hatching rate of A.calandrae increased first and then decreased with the increase of temperature.When the temperature was 25°C,the hatching rate of the larvae reached the highest value,which was88.67%.The survival rate of A.calandrae larvae decreased with the increase of temperature;there was a significant negative correlation between temperature and the developmental duration of each insect state,that is,the developmental period was significantly shortened with the increase of environmental temperature.The adult lifespan of A.calandrae showed a shortening trend with the increase of temperature.The average life expectancy at 22°C was 17.88d,the average life expectancy at 31°C was only 9.89d,and the adult egg production increased with the increase of temperature.The developmental threshold temperature and the effective accumulated temperature for generation were 17.81℃and 138.48 degree-days,respectively.The parameters indicate that the line regression and the Logistic model are more suitable for the relationship between the development rate and temperature of A.calandrae than the"Wang-Lan-Ding"model.The results suggest that the temperature has a significant effect on the development and reproduction of A.calandrae,and the optimum temperature range for its growth and reproduction is between 25-31℃.4.Biological characteristics of A.calandrae propagated by different hostsIn order to explore the effects of different hosts on the biological characteristics of A.calandrae,four kinds of storage pests were provided for the spawning for A.calandrae.The selection of A.calandrae to four different hosts,developmental duration,egg production and the quality of A.calandrae of different host reproduction were investigated.The results showed that A.calandrae had a highest selection rate of L.serricorne,which was 77.37%,followed by the selection rate of C.chinensis,which was 14.6%,and the selection rate of A.obtectus and S.zeamais was 5.63%,2.4%.The developmental duration of A.calandrae on L.serricorne,C.chinensis,A.obtectus and S.zeamais was 17.6 d,17.99 d,18.9 d and 18.89 d,respectively.When A.calandrae hosted the L.serricorne,the single female had the highest amount of bee,52.1 heads,The single female lays on C.chinensis is 32.5 heads,the A.obtectus is 11.7 heads,and the S.zeamais is only 9.75.The masses of A.calandrae propagated by L.serricorne,C.chinensis,A.obtectus,and S.zeamais were:6.27 mg/10 head,6.01 mg/10 head,5.50 mg/10 head,5.27mg/10 head.The four hosts（L.serricorne,C.chinensis,A.obtectus,S.zeamais）can satisfy the growth and development of A.calandrae larvae,but A.calandrae has higher selectivity and shorter developmental duration for L.serricorne and C.chinensis.The quality of the first-feathered adult wasps on both hosts is greater,indicating that L.serricorne and C.chinensis are more suitable for spawning of A.calandrae.5.Effects of different hosts on the biological characteristics of A.calandraeThis study aims to evaluate the control effects of A.calandrae on the L.serricorne,providing a reference for the storage release application of A.calandrae.The laboratory population life table of L.serricorne and A.calandrae was prepared under laboratory conditions of 25±1℃,RH 70%±5%and 14L:10D,and the parasitic functional responses,and the density effect of A.calandrae,as well as spatial heterogeneity experiments were determined.Through the comparison of life table parameters and functional reaction model analysis,it can be seen that A.calandrae has a strong parasitic ability to the larvae of L.serricorne,high reproduction rate and strong control ability to the L.serricorne population.The A.calandrae period is 29.88 d,the A.calandrae period is 70.78 d,that is,the L.serricorne completes one generation,and the A.calandrae can complete about 2-3 generations.The functional response of A.calandrae against L.serricorne larvae and pupa is consistent with the Holling II model,and the HollingⅡequations are:Na=0.7316N₀/1+0.0517N₀、Na=1.0452N₀/1+0.2015N₀.The functional response of A.calandrae to L.serricorne showed that the number of larvae and tobacco hyperthyroidism of the single-headed female bee was up to 14.14 and 5.19,respectively,within 24 h.The density of A.calandrae also affected its parasitism to host and the relation could be described as Hassell-Varley:a=0.0804 Pt^-0.4055.The spatial heterogeneity of A.calandrae indicates that A.calandrae has the best parasitic effect of corn slag and tobacco larvae with tobacco leaves as food.For bare L.serricorne larvae,A.calandrae never spawns parasitic.Therefore,in the breeding and the release technology of A.calandrae should be taken to take full advantage of the natural enemy’s control potential.Through this experiment,it was found that the density of itself has a certain interference effect on the parasite of A.calandrae.However,the A.calandrae population grows faster than L.serricorne,and can be used to control the vaccination in the cigarette warehouse.In the application of natural enemy insects,parasitic wasps are one of the longest and most widely used groups in the field of biological control.In this paper,L.serricorne and A.calandrae were used as the test source.The parasitic wasps of L.serricorne in Guiyang were investigated.And the biological characteristics of the dominant parasitic wasp A.calandrae in L.serricorne were observed.And the A.calandrae at different temperatures was discussed.According to the law of effective accumulated temperature,the developmental starting temperature and effective accumulated temperature of the insects are calculated according to the law of effective accumulated temperature.Four different storage pests were selected as hosts to investigate the selectivity of A.calandrae to different hosts and the effects of different hosts on the growth and reproduction of A.calandrae.At the same time,the L.serricorne age characteristic life table and the reproduction of A.calandrae parasitic L.serricorne were compiled.The parasitic functional response of the larvae of A.calandrae parasitic L.serricorne was studied.The control potential of A.calandrae against L.serricorne larvae was evaluated by comparison of life table parameters and functional response analysis.The research results can provide a favorable reference for controlling beetle storage pests,and further explore the basis of A.calandrae parasitic mechanism.