| Frankliniella occidentalis is an important invasive pest on horticultural crops worldwide. Itwas first found in China in2003, and it is distributed in Beijing, Yunnan, Shandong, Guizhou, andXinjiang, caused serious damage to the vegetables and flowers production. Frankliniellaoccidentalis can transmit many kinds of plant viruses. Frankliniella occidentalis is the mosteffective transmission vector of tomato spotted wilt virus (TSWV), and the damage caused by theviruse is greater than itself made. TSWV has already been detected in Beijing, It will cause seriousdamage to the vegetables and flowers if the viruse continute to spread. In the current study, weinvestigated the distribution of TSWV in Beijing, explored the feeding behaviors ofspinosad-susceptible and-resistant F. occidentalis strains, and TSWV-infected and uninfectedinsecticide resistance and susceptible F. occidentalis strains using electronic penetration graph(EPG) technology. At last, we proposed an effective pesticide and its best application method tocontrol Frankliniella occidentalis. The specific findings are as follows.(1) Tomato spotted wilt virus (TSWV) was identified on eggplant and pepper plants in someregions of Beijing by using TSWV specific detection kit and further validated by the RT-PCR andgene sequencing. The major thrips that occurred on the eggplant and pepper were western flowerthrips which carried the virus as well. Tomato spotted wilt virus disease can cause serious damageto many kinds of crops. Departments should take precaution and management measures to preventthe disease spreading.(2) Resistence to spinosad effect the Frankliniella occidentalis feeding behavior on host plants.The Frankliniella occidentalis feeding behavior has no difference on datura, pepper, and tomato,nomatter spinosad-susceptible or-resistant strains. But it has significantly defference betweensusceptible and resistant strains..Spinosad-susceptible strain feeds better than the resistant strainson datura, pepper, and tomato,. Specifically, the tolal number of probes,tolal duration ofprobes,number of noingestion probes and total duration of noingestion probes,number ofshort-ingestion probes and total duration of short-ingestion probes,and number of long-ingestionprobes of susceptible strain were higher than resistant strains on datuar; the tolal number of probes,number of short-ingestion probes and total duration of short-ingestion probes and long-ingestionprobes of susceptible strain were highter than resistant strains on pepper; it was similar betweentomato and datuar,and seven parameters of susceptible strain were highter than resistant strains.(3) The feeding behaviors of spinosad-susceptible and-resistant strains can be modified by TSWV in the indirect (plant infection) and direct (thrip infection) ways. TSWV infection canimprove the feeding behaviour of spinosad susceptible and resistant strains in a manner whichenhances viral transmission.The,number of noingestion probes and total duration of noingestionprobes,number of short-ingestion probes and total duration of short-ingestion probes of susceptiblestrain is higher than resistent strain.At the same time, spinosad susceptible strain fed more readilyand have more virus transmission potential than resistant strain, regardless of the infection status ofTSWV.(4) Three insecticides, abamectin, thiamethoxam, and spirotetramat, which were commonlyused in fields, were selected to compare their residual toxicities to the F.occidentalis (Pergande) onpotted cabbage, sweet pepper, and kidney bean plants by using drenching and spraying methods.The old and new leaves were cut from the above plants at different time and brought back tolaboratory to test their residual activities by using Eppendorf tube method. The results showed thatthiamethoxam applied by drenching method provided the highest residual activity and the activitylasted more than one month, which could be recommended to use in controlling the western flowerthrips especially during the seedling stage. |
