The Efficiency By Western Flower Thrips,Frankliniella Occidentalis Transmiting Tomato Spotted Wilt Virus On Different Host Plants

Western flower thrips, Frankliniella occidentalis are the important insects in the crops, and they are the most efficient transmitters for tomato spotted wilt virus and cause huge losses on crops every year. Transmission efficiencies for tomato spotted wilt virus were comparatively studied using leaf disks of four host plants, which were tomato, pepper, petunia and stramonium.In this study, the feeding behaviors for healthy and infected western flower thrips on tomato, pepper, stramonium and petunia were recorded using the direct current electrical penetration gragh (DC-EPG). To determine if it carried TSWV or not, the individual infected western flower thrips was tested by RT-PCR. All results are follows:l.Only between10percent and thirty percent western flower thrips can acquire TSWV and transmit it to plants successfully. The result showed that the transmission efficiency by western flower thrips of TSWV on four different host plants were no significant difference. It means that the transmission efficiences by infected western flower thrips are similar on different suitable host plants. The efficiency by infected western flower thrips transmiting TSWV will not became significant difference because of the change of the species of host plants.2.The results of feeding behaviour of uninfected western flower thrips on four host plants:(1) The comparison among different host plants:The noningestion probes for WFT on pepper were significantly less than that on other host plants. The number of noningestion probes for females on pepper, tomato, stramonium and petunia was231.1,328.9,361.0and304.4, respectively. The number of noningestion probes for males on pepper, tomato, stramonium and petunia was152.7,277.2,221.4and196.8, respectively. Compared with tomato, the short-ingestion probes for WFT was significantly greater on petunia. The number of short-ingestion probes for females on tomato and petunia was68.8and144.4, respectively. The number of short-ingestion probes for males on tomato and petunia was15.9and80.9, however. The long-ingestion probes on petunia were less than that on other host plants.(2) Pairwise comparison for female and male thrips. The noningestion probes and short-ingestion probes for females were more than those for males, however, the long-ingestion probe for males was more than that females. The number and the duration of noningestion probes for females on petunia were1.5times of that for males. Compared with females, the number and duration of short-ingestion probes for males was4times and2times of those for females on tomato, respectively. The number and the duration of long-ingestion probes for males was2times and7times of that for females on tomato, respectively. From these results, we concluded that the feeding behavior of western flower thrips on host plants doesn’t have close relation to the suitability of host plants.3. The results of feeding behavior for WFT which infected with TSWV on four host plants:(1) The comparison among different host plants:The short-ingestion probes for WFT on petunia and stramonium was significantly higher than other host plants. The number of short-ingestion probes for females on tomato, pepper, stramonium and petunia was73.7,66.7,137.3and197.9, respectively. The long-ingestion probes for WFT on petunia was significantly less than other host plants. The number of long-ingestion probes for females on tomato, pepper, stramonium and petunia was1.3,1.5,0.7and0.6, respectively.(2) The comparison between females and males:The short-ingestion probes for females was more than those for males, however, the long-ingestion probes for males was more than that females. The number of short-ingestion probes for females on tomato, stramonium and petunia were all3times of that for males. The total duration of short-ingestion probes for females was on petunia was2times of that for males Compared with females, the number of long-ingestion probes for males were both2times of those for females on stramonium and petunia, respectively. The total duration of long-ingestion for males on tomato and petunia was2times and3times of that for females, respectively. From these results, we can explain why males with TSWV have been more efficient vectors of TSWV than females on feeding behavior.And we can also conclude that the feeding behavior of western flower thrips with TSWV on host plants doesn’t have close relation to the suitability of host plants.