Abstract
The impacts of infestation by the green peach aphid (Myzus persicae) on sweetpotato whitefly (Bemisia tabaci) settling on tomato were determined in seven separate experiments with whole plants and with detached leaves through manipulation of four factors: durations of aphid infestation, density of aphids, intervals between aphid removal after different durations of infestation and the time of whitefly release, and leaf positions on the plants. The results demonstrated that B. tabaci preferred to settle on the plant leaves that had not been infested by aphids when they had a choice. The plant leaves on which aphids were still present (direct effect) had fewer whiteflies than those previously infested by aphids (indirect effect). The whiteflies were able to settle on the plant which aphids had previously infested, and also could settle on leaves with aphids if no uninfested plants were available. Tests of direct factors revealed that duration of aphid infestation had a stronger effect on whitefly landing preference than aphid density; whitefly preference was the least when 20 aphids fed on the leaves for 72 h. Tests of indirect effects revealed that the major factor that affected whitefly preference for a host plant was the interval between the time of aphid removal after infestation and the time of whitefly release. The importance of the four factors that affected the induced plant defense against whiteflies can be arranged in the following order: time intervals between aphid removal and whitefly release > durations of aphid infestation > density of aphids > leaf positions on the plants. In conclusion, the density of aphid infestation and time for which they were feeding influenced the production of induced compounds by tomatoes, the whitefly responses to the plants, and reduced interspecific competition.
Highlights
The sweetpotato whitefly, Bemisia tabaci (Gennadius), is an exotic insect pest in China and causes severe damage by direct feeding and transmitting viruses on various vegetables, ornamental and field crops [1,2]
Our observations indicate that M. persicae influenced the responses of B. tabaci adults to tomato plants in both direct effects when aphids were present and indirect effects on plants preinfested by the aphids
Aphids penetrate the leaf of the host plant through their stylets and induce plant responses through plant hormone regulation, defensive protein expression and secondary metabolite emission[45,46,47]
Summary
The sweetpotato whitefly, Bemisia tabaci (Gennadius), is an exotic insect pest in China and causes severe damage by direct feeding and transmitting viruses on various vegetables, ornamental and field crops [1,2]. Many appropriate strategies have been promoted to suppress B. tabaci taking into consideration their characteristics of high plasticity adaptation to the environment, wide host plant range and strong pesticide resistance [3,4,5,6]. B. tabaci faces competition from native phytophagous arthropods which are in the same niche and share a similar food range. Previous work has indicated that competition exists between B. tabaci and Trialeurodes vaporariorum (Westwood) on greenhouse-grown vegetables and ornamentals [3]. Colonization of B. tabaci may negatively influence the development and survival of the cabbage looper, Trichoplusia ni (Hubner) and the vegetable leafminer, Liriomyza sativae (Blanchard) [8,9]. The occurrence of other herbivores might influence the colonization of B. tabaci via host plant induced defense reactions [11,12,13]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
