ARS | Publication request: Influence of pymetrozine on feeding behaviors of three rice planthoppers and a rice leafhopper using electrical penetration graphs

Submitted to: Journal of Economic Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 17, 2011
Publication Date: December 1, 2011
Citation: He, Y., Zhang, J., Chen, J., Wu, Q., Chen, L., Chen, L., Xiao, P., Zhu, Y. 2011. Influence of pymetrozine on feeding behaviors of three rice planthoppers and a rice leafhopper using electrical penetration graphs. Journal of Economic Entomology. 104(6):1877-1884.

Interpretive Summary: Pymetrozine reportedly inhibited feeding of plant sap-sucking insects, such asaphids and brown planthopper. By using electrical penetration graph (EPG), this study was conducted to investigate any differential effects of pymetrozine on the feeding behaviors of four major rice sap-sucking insect species, including three planthoppers and one leafhopper. On pymetrozine-free TN1 rice plants, the white-backed planthopper and small brown planthopper showed a little less activity in the phloem periods and rice leafhopper had a relatively higher xylem feeding than BPH. On the plants treated with 100 mg per litre of pymetrozine, all four insect species showed significant increase in total duration of non-probing phases and substantial decrease in the activities in phloem region, while all species showed similar feeding behavior during the pathway and xylem phases. This study revealed that phloem and xylem sap regions were necessary for rice planthoppers and rice leafhopper. In spite of the difference of phloem and xylem feeding preferences, the feeding behaviors of planthoppers and leafhopper were disturbed by pymetrozine with similar patterns of a sharp decline of the activity in the phloem region and a significant increase of the non-probing periods.

Technical Abstract: Pymetrozine reportedly inhibited feeding of plant sap-sucking insects, such as aphids and brown planthopper (BPH), Nilaparvata lugens. By using electrical penetration graph (EPG), this study was conducted to investigate any differential effects of pymetrozine on the feeding behaviors of four major rice sap-sucking insect species, N. lugens, white-backed planthopper (WBPH), Sogatella furcifera, small brown planthopper (SBPH), Laodelphax striatellus and green rice leafhopper (GRL), Nephotettix cincticeps. On pymetrozine-free TN1 rice plants, WBPH and SBPH showed a little less activity in the phloem periods and GRL had a relatively higher xylem feeding than BPH. On the plants treated with 100 mg litre-1of pymetrozine, all four insect species showed significant increase in total duration of non-probing phases and substantial decrease in the activities in phloem region, while all species showed similar feeding behavior during the pathway and xylem phases. This study revealed that phloem and xylem sap regions were necessary for rice planthoppers (BPH, WBPH and SBPH) and rice leafhopper (GRL). In spite of the difference of phloem and xylem feeding preferences, the feeding behaviors of planthoppers and leafhopper were disturbed by pymetrozine with similar patterns of a sharp decline of the activity in the phloem region and a significant increase of the non-probing periods.