| Rice stem borer(RSB),Chilo suppressalis(Walker),belongs to Lepidoptera,Pyralidae,is one of the most serious pests that damage rice In China.With the widespread implementation of green agriculture and the popularization of sustainable control strategy to pests,in order to reduce the harm on agriculture ecosystem and a series of adverse effects of insect resistance caused by the use of chemical pesticides,using sex pheromone in the rice stem borer control is particularly important.In this thesis,to develop a lure with multi-function and high control efficiency,based on investigation of effects of Zizania latifolia,rice stem and the artificial diet as the food sources of C.suppressalis on its development and fecundity,the attractant effect and mechanism of RSB'sex pheromone combined with sex pheromone from rice leaf roller(RLR),Cnaphalocrocis medinalis Guenée,on RSB were explored.Then,effects of plant volatiles from Vetiveria zizanioides on attracting ovipostion of C.suppressalis female moths were studied to develop an attractant of females of C.suppressalis.Meanwhile,the volatiles from V.zizanioides were combined with RSB's sex pheromone to screen the plant chemicals which enhanced attracting effects of sex pheromone lure for RSB males.C.suppressalis were fed by the Zizania latifolia,rice stem and artificial feed.The result showed that RSB's larval duration was the shortest in the Z.latifolia treatment,and the mortality rate,pupation rate and emergence rate also were slowest,were(16.00±0.81)%,(32.76±0.31)%and(66.90±0.71)%,respectively,while pupal duration was the longest,e.i.,19.40±0.68 days.When RSB larvae were fed with the artificial diet,the larval duration(32.2±1.64 days)was the longest,and sex ratio of the adults(57.58±0.51%)was relatively low.However,in the rice stem treatment,pupation period was the shortest(16.80±0.66 days),and the sex ratio of adult(55.08±0.66%)was the lowest.On the whole,the artificial feed was feasible for RSB feeding,and Z.latifolia was the most suitable for development of larvae but unsuitable for indoor continued breeding.Rice stem was suitable for indoor continued breeding C.suppressalis.The previous field experiments showed that no C.suppressalis.male moths were traped when RSB's lures combined with lures of RLR sex pheromone.The indoor behavior experiment and field test on the lures and single lures to the two stem borer were carried out to investigate the mechanism of the phenomenon.The results showed that the effective components of Z11-18:OH and Z13-18:OH in lures of RLR sex pheromone had a repellent effect on C.suppressalis male moths.The field experiments indicated that the number of trapping insects reduced when Z11-18:OH or Z13-18:OH added to the lure of C.medinalis respectively,few male moths were trapped when Z11-18:OH and Z13-18:OH added together,and it was significantly different with the number of single using lures of RLR sex pheromone.The results confirmed that the two kinds of alcohol were repellent to C.suppressalis male moths,and revealed that the simple mixed lures had no synergism even had an inhibitory effect on the trapping.The findings would help to guide the rational use of pest sex pheromone for agricultural producers,and provided the basis for the design of green techniques of field repellents for RSB control.In order to develop botanical attractants for females of rice stem borer,C.suppressalis(Lepidoptera:Cramiridae),the orientational behavioral responses of C.suppressalis females to plant the volatiles substances from vetiver,V.zizanioiaes,were studied by use of electroantennograph(EAG)and wind tunnel techniques.The results showed that all 16kinds of the vetiver substances could provoke the EAG responses of female moths,and the EAG responses to oleic acid and cholesterol at concentration of 0.1?g/?L?1.0?g/?L?10.0?g/?L were strengthening with the increasing of concentration,but it decreased for citral,bornan-2-one and palmitic acid.The EAG value of C.suppressalis females to vetiver extracts at concentration of 1.0?g/?L was 426.11×10~-33 Mv that was significantly higher than other standard compounds(P<0.05).C.suppressalis females could be attracted by the volatile compounds including cholesterol,citral,n-Pentadecanoic acid,myristic acid,glycerol 1-palmitate and diisooctyl phthalate in wind tunnel assasys,and those mixtures of different ratios that have attractive effects on the female moths were screened as follows,Cholesterol:Citral:Myristic acid=33:24:11,Diisooctyl phthalate:Citral:Glycerol1-palmitate=130:48:1,Cholesterol:Citral:Myristic acid:Glycerol 1-palmitate=66:48:22:1,Citral:Glycerol 1-palmitate=48:1,respectively.These vetiver volatile compounds with electrophysiological and behavioral activities to C.suppressalis females in the laboratory would lay an important base to develop plant attractants for the moths.To explore the synergism of the volatile substances from V.zizanioides to C.suppressalis sex pheromone,orientation behavior tests were conducted by mixtures of 10standard compounds from vetiver volatiles and 21 the volatile substances from V.zizanioides matching C.suppressalis sex pheromone.The resulted showed that V.zizanioides volatiles of citral,durene,linalool,cholesterol had obviously attractant effect on RSB male moths.Mixtures of radios of sex pheromone:citral=2:1,sex pheromone:bornan-2-one=2:1,sex pheromone:Glycerol 1-palmitate=2:1,citral:cholesterol=1:1,durene:cholesterol=1:1,sex pheromone:bornan-2-one:citral=2:1:1 showed the stronger attractant effect on C.suppressalis male moths.Mixtures of vetiver volatiles of camphor,citral was the most prominent,had a significant effect on single and mixed temptation.In the experiment,synergism of the volatile substances from V.zizanioides to C.suppressalis sex pheromone in performance of indoor wind tunnel orienting behavior were very significant,but were not well reflected in the field test,the need for follow-up to further explore the most appropriate release agent and proportion. |
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