[Effects of volatiles from chestnut on host preference of adult Conogethes punctiferalis (Lepidoptera: Pyralidae)].

Through field survey and the tests of behavioral response, EAG response, and multiple-choice oviposition, this paper studied the effects of volatiles from Nongda No. 1 chestnut (NC) and Heyuan oil chestnut (HC) on the host-selection behavior of adult Conogethes punctiferalis. The field survey in 2004-2008 showed that the moth-eaten rate of NC fruits by adult C. punctiferalis was 16.1%-25.3%, while that of HC fruits was less than 5%. The volatiles from NC fruits and leaves were more attractive to female than to male moths, and the fruit volatiles were more attractive than leaf volatiles. However, the volatiles from HC fruits and leaves were not attractive to both female and male moths. The EAG response showed that female moths had significantly higher response to NC fruit volatiles than to HC's, but male moths had no significant difference in this response. For both NC and HC, the EAG responses of female and male moths to fruit volatiles were higher than those to leaf volatiles. The number of eggs laid by female moths was much greater on NC fruits than on NC leaves and on HC fruits and leaves, but had no significant differences on the latter three.

[Controlling effects of plant extracts and pesticides on Myzus persicae and Lipaphis erysimi populations].

This paper studied the controlling effects of Xanthium sibiricum and Syngonium podophyllum ethanol extracts, mobile oil emulsion and 0.3% azadirachtin EC on Myzus persicae and Lipaphis erysimi populations both in laboratory and in field. The results showed that in laboratory, X. sibiricum extract was the key deterrent to Myzus persicae, while sprayed it with S. podophyllum extract and with petroleum spray oil or 0.3 % azadirachtin EC, the deterrent effect could be improved. As for pterigota Lipaphis erysimi, the extracts of the two plants were the main deterrents, and their interference effect was non-linear. In field, S. podophyllum extract had a stronger deterrent effect when sprayed independently. L. erysimi population could be successfully controlled by the mixtures of plant extracts and insecticides, with an efficiency of 95.7%. The best treatment against M. persicae population was X. sibiricum extract, with an efficiency of 87%, while S. podophyllum extract mixed with 0.3% azadirachtin EC, and X. sibiricum extract mixed with 0.3% azadirachtin EC had an efficiency of >80%.

[Suppressive effects of non-preferable plant alcohol extracts on diamondback moth Plutella xylostella population].

In this paper, a life table and an interference index of population control (IIPC) were used to evaluate the effects of spraying the alcohol extracts of non-preferable plants on the dynamics of diamondback moth Plutella xylostella) population. The results showed that the alcohol extracts of Eupatorium odoratum, Lantana camara and Wedelia chinensis were available to protect kidney bean from Plutella xylostella infestation. Their IIPC were 0.110, 0.136 and 0.165, and the efficacies of controlling P. xylostella were 89.0%, 86.4% and 83.5%, respectively, compared with control.

[Effect of plant alcohol extracts on vegetable aphids and their parasitoids].

The repelling and controlling effect of alcohol extracts from 8 common plant species on 3 major vegetable aphids (Myzus persicae, Aphis gossypii and Lipaphis erysimi) were studied in the laboratory, and the effect on their parasitoid was also studied. The results showed that the test 8 plant species had some effects on 3 aphids. The plant alcohol extracts from Tephrosia vogelli and Cinnamomum camphora had the most effect. The deterrent rate on Myzus persicae, Aphis gossypii and Lipaphis erysimi was 0.414, 0.729, 0.547 and 0.549, 0.690, 0.729, respectively. These 2 plants had the most controlling effect on 3 aphids, too. The alcohol extract of Cinnamomum camphora was safely for parasitoids (Aphidius gifuensis and Diaeretiella rapae).

[Chemical components of volatile oil from Mikania micrantha and its biological activity on insects].

The chemical components of volatile oil from Mikania micrantha were analyzed by GC/MS. Twenty-two compounds were identified, and monoterpenes and sesquiterpenes as well as alcohol and ketone with their derivatives were major components. Biological activity of volatile oil on insect was investigated. The results showed that the volatile oil had significant deterrent effect on oviposition of Plutella xylostella, Phyllotreta striolata and Phaedon brassicae at dose of 5-10 microliters.plant-1. They also possessed established contracting toxicity, and their rectifying reduce rates for Lipaphis erysimi were 50.0%, 59.86%, 62.51% at concentration of 500, 750, and 1000 mg.L-1, respectively. However, they had not fumigating toxicity for virginogeniae, L. erysimi, 2nd instar larvae of P. xylostella, and adult of P. striolata at concentration of 500 mg.L-1.