The effects of semiochemicals extracted from 63 species of plants, on peach aphid (Myzus per-sicae) and mustard aphid (Lipaphis erysimi), were studied in laboratory. The deterrent rate, reproduction deterrent index an...The effects of semiochemicals extracted from 63 species of plants, on peach aphid (Myzus per-sicae) and mustard aphid (Lipaphis erysimi), were studied in laboratory. The deterrent rate, reproduction deterrent index and the interferential index of population control (IIPC) was used to evaluate the efficiency of semiochemicals on population control of the two target aphids. The results showed that the extracts of 34 species of common plants have noticeable effect on both aphid populations, especially, Xanthium sibiricum Petr. Et Widd. and Syngonium podophyllum Schott. These plant extracts could be used to construct the plant pro-tectant to protect crops.展开更多
For long-term prediction of occurrence degree of tobacco aphid Myzus persicae （Sulzer）, Markov chain method was used to establish prediction model for occurrence degree of tobacco aphid. With 4 levels of occurrence ...For long-term prediction of occurrence degree of tobacco aphid Myzus persicae （Sulzer）, Markov chain method was used to establish prediction model for occurrence degree of tobacco aphid. With 4 levels of occurrence degree, Markov chain model was established based on the data in 1987-2004. The results indicated that the accuracy for total prediction in 2005-2007 and the back prediction in 1987-2004 reached 88.89% and 85.12%, respectively. The method is simple and feasible for long-term prediction of occurrence degree of tobacco aphid.展开更多
The green peach aphid, Myzuspersicae (Sulzer), is a major insect pest of many agronomic and horticultural crops and is distributed worldwide. Aphid management is often based on application of insecticides. However, th...The green peach aphid, Myzuspersicae (Sulzer), is a major insect pest of many agronomic and horticultural crops and is distributed worldwide. Aphid management is often based on application of insecticides. However, the aphid is now resistant to many of these and much interest has recently developed in identification of novel alternative insecticides. Venom isolated from the red imported fire ant, Solenopsisinvicta Buren, is composed of two groups of alkaloids, piperidines and piperideines, and has shown activity against many organisms including fungi, bacteria, mites and several insects. Prior to the study reported herein, no information on the venom’s activity to Myzuspersicae has been reported. Both of the alkaloids were active against M.persicae. The 24 h LC50 values were116.6 and 91.5 ppm for the piperideine and piperidine extracts, respectively. Based on overlap of the 95% fiducial limits the LC50 values for the two alkaloids did not significantly differ. At the high dosages, mortality occurred in as few as four hours and all treated aphids were dead by six hours. Little additional mortality was detected in the 48-hobservation. Both piperideine and piperidine extracts isolated from red imported fire ant venom possess sufficient activity to cause death of green peach aphids and at high dosages, death occurs rapidly. In the search for new replacements to synthetic insecticides, these extracts may offer a novel but potentially successful alternative.展开更多
文摘The effects of semiochemicals extracted from 63 species of plants, on peach aphid (Myzus per-sicae) and mustard aphid (Lipaphis erysimi), were studied in laboratory. The deterrent rate, reproduction deterrent index and the interferential index of population control (IIPC) was used to evaluate the efficiency of semiochemicals on population control of the two target aphids. The results showed that the extracts of 34 species of common plants have noticeable effect on both aphid populations, especially, Xanthium sibiricum Petr. Et Widd. and Syngonium podophyllum Schott. These plant extracts could be used to construct the plant pro-tectant to protect crops.
基金Supported by Tobacco Monopoly Bureau of Shandong Province (KN90)
文摘For long-term prediction of occurrence degree of tobacco aphid Myzus persicae （Sulzer）, Markov chain method was used to establish prediction model for occurrence degree of tobacco aphid. With 4 levels of occurrence degree, Markov chain model was established based on the data in 1987-2004. The results indicated that the accuracy for total prediction in 2005-2007 and the back prediction in 1987-2004 reached 88.89% and 85.12%, respectively. The method is simple and feasible for long-term prediction of occurrence degree of tobacco aphid.
文摘The green peach aphid, Myzuspersicae (Sulzer), is a major insect pest of many agronomic and horticultural crops and is distributed worldwide. Aphid management is often based on application of insecticides. However, the aphid is now resistant to many of these and much interest has recently developed in identification of novel alternative insecticides. Venom isolated from the red imported fire ant, Solenopsisinvicta Buren, is composed of two groups of alkaloids, piperidines and piperideines, and has shown activity against many organisms including fungi, bacteria, mites and several insects. Prior to the study reported herein, no information on the venom’s activity to Myzuspersicae has been reported. Both of the alkaloids were active against M.persicae. The 24 h LC50 values were116.6 and 91.5 ppm for the piperideine and piperidine extracts, respectively. Based on overlap of the 95% fiducial limits the LC50 values for the two alkaloids did not significantly differ. At the high dosages, mortality occurred in as few as four hours and all treated aphids were dead by six hours. Little additional mortality was detected in the 48-hobservation. Both piperideine and piperidine extracts isolated from red imported fire ant venom possess sufficient activity to cause death of green peach aphids and at high dosages, death occurs rapidly. In the search for new replacements to synthetic insecticides, these extracts may offer a novel but potentially successful alternative.
