| Since Tetranychus urticae Koch invaded into China, it has spread quickly and became the important pest of crops. In early studied, the bean damaged by T. urticae which had significant adverse influence on Frankliniella occidentails, and T. urticae had obvious interspecific competition with F. occidentails. Tomato was chosen as host plant. We studied the physiological and biochemical effects of tomato which damaged by T. urticae and explored its role in the response to F. occidentails defense.We studied the behavior and physiology of F. occidentails after it feed the tomato damaged by T. urticae. The mechanisms of their interactions will be known from this research, and which would provide theoretical basis for their integrated management.The main results were as follows:1 Behavior responses of F. occidentails to tomato infested by T.urticae and analysis of volatile componentsThe results of the percentages of F. occidentalis to tomato damaged by T.urticae at different densities and time showed that F. occidentalis was more likely to select tomato damaged for 1 d, when density were 5 mites/plant and 15 mites/plant,respectively. F. occidentalis showed a significant preference for the 25 mites/plant infested 2 d, with the rate of choice of 39.56%, and the choice to clean plant and plant damaged for 1 d did not show significant differences. F. occidentalis tended to select tomato damaged by 15 mites/plant, no matter T. urticae infested 1 d or 2 d. F.occidentalis was most attractive to tomato infested with 5 mites/plant, which was damaged for 3 d. The results showed that percentages of F. occidentalis to tomato damaged by T. urticae had relation with the damaged density and time, and F.occidentalis was attracted to tomato damaged by T. urticae at medium degree.There were 38 types of compounds identified in the tomato damaged by T.urticae. The highest levels of the compounds were β-phellandrene,(Z)-3-hexen-1-ol and(+)-2-carene which of the proportion was 63.83%~73.26%. The components and contents of volatiles from mites-infested plants were significantly different than that from healthy tomato plant.(+)-2-carene and β-phellandrene were lower. The tomato damaged by T. urticae was induced to produce aromadendrene. O-cymene,2-methyl-1-butano and(E)-2-hexenal were only found in tomato plant that were damaged by spider mite at higher degree. It was guessed that m-cymene and O-cymene might be repellent to F. occidentalis, while P-cymene and 1-octen-3-ol were attractive to F. occidentalis.2 Effects of T. urticae feeding on the contents of main nutrient and protective enzymes of tomatoT. urticae damaged on tomato plant could cause significant change of the nutrient contents. The soluble sugar content in damaged tomato was significant lower than healthy tomato. As the extension of feeding time, the content change of soluble sugar was relative with the mites density. The change of the soluble protein content also had relation with T. urticae. When T. urticae infested 3 d, the soluble protein content decreased biggest, it fell by 46.65% at 25 mites/leaf. When 15mites/leaf and 25 mites/leaf damaged at 2 d, free amino acid was significant higher.These results indicated that tomato plants might reconfigurate the content of nutrient to response the mites damaged.The POD activity of tomato damaged by T. urticae was always higher than that in healthy plants. The POD activity at 25 mites/leaf damaged 2 d was highest, with the value of 153 U/mg prot. The activity of PAL was the highest in 15 mites/leaf damaged 2 d. The same change was found in PPO activity. No matter in any damaged density, PPO activity was the highest in 2 d, which increased by 25.31%,30.81% and 12.84% respectively compared to control plant. The change of LOX was similar to PAL. T. urticae damaged induced LOX activity significantly higher than healthy plant. We can conclude that T. urticae damage induced tomato plants resistance defense which caused POD, PAL, PPO and LOX activity changed.3 Effects of tomato plant defensive response induced by T.urticae on behavior of F. occidentalisT. urticae feeding at different densities and different time had significant influence on tomato chlorophyll and secondary metabolism(flavone, tannin). After the mites damaged, the content of chlorophyll was significantly lower than that of healthy plants. The content of flavone was minimum at 5 mites/leaf damaged at 7 d and 15 mites/leaf damaged at 5 d. When 5 mites/leaf damaged, the content tannin of5 mites/leaf was highest at 5 d, which increased 75% than healthy tomato. When 15mites/leaf damaged at 3 and 5 d, the content of tannin were significantly higher than healthy plants. We can concluded that tomato plants had changed the content of chlorophyll and metabolism to deal with the threat of mites.The number of np, p were highest with 5 mites/leaf damaged at 5 d, but there was not obvious difference between different treated tomato. The number of S were lowest with 5 mites/leaf damaged at 7 d. The number of Q were very low, and there was not significant difference. The change of R was similar to S wave, and the same change was found on duration time. On the healthy and damaged tomato, the duration of np and p were no significant difference. No mater in healthy or damaged tomato, the average duration of p, S, Q and R were less than 60 s. The results showed that tomato plants damaged by T. urticae had negative influence on F.occidentalis.4 Effects of tomato plant defensive response induced by T.urticae on enzyme activity, development and fecundity of F.occidentalisWhen F. occidentalis feed on healthy tomato and mites damaged tomato, the enzyme activity(POD, CAT, T-SOD, CES, GST and MFO) in it were changed. The enzyme activity of POD, CAT, CES, GST and MFO were highest at 5 mites/leaf damaged at 3 d. But the activity of T-SOD were always lower than healthy plants.These results showed that tomato plant defensive response induced by T. urticae would influence the enzymes activity of F. occidentalis.The development and fecundity of F. occidentalis were significant difference when feeding different treated tomato. The duration of 1st instar nymph were longest on healthy tomato and 5 mites/leaf damaged at 5 d. The duration of 2st instar nymph were longest at 5 mites/leaf damaged at 3 d with 5.37 d. Both prepupa and pupap were slowest at 15 mites/leaf damaged at 5 d. The duration time of immature was longest at 5 mites/leaf damaged at 3 d with 11.02 d. The duration of preoviposition,post-oviposition and oviposition were lowest at 15 mites/leaf damaged at 3 d and 5mites/leaf damaged at 5 d. The fecundity of F. occidentalis was also obvious differences among different treated tomato. Whether fecundity per female per day or fecundity per female, the fecundity of F. occidentalis were highest at 5 mites/leaf damaged at 5 d. The life of female adult were shortest both on 15 mites/leaf damaged at 3 d and 5 mites/leaf damaged at 5 d. We could conclude that tomato plants induced by T. urticae had defensive response to F. occidentalis. |
PDF Full Text Request