摘要:

First-instar grasshoppers infected withMelanoplus sanguinipesentomopoxvirus consumed 25% less food within 5 d (75 degree-days (DD), base 10°C) after inoculation with 5 × 103virus occlusion bodies. Grasshoppers ate 25 and 40% less food by the end of the second week (200 DD, base 100°C) after being infected as first instars with 5 × 102and 5 × 103occlusion bodies per individual, respectively. When infected as third instars with 1 × l04and 1 × 105occlusion bodies per individual, grasshoppers ate 20 and 35% less food by the second week of the study, respectively. The mean amount of food consumed by infected grasshoppers over the course of the study was 36, 31, 76, and 57% that of noninfected grasshoppers at dosages of 5 × 102or 5 × 103occlusion bodies per first instar, and 1 × 104or 1 × 105occlusion bodies per third instar. This study suggests that an application of entomopoxvirus to first-instar grasshoppers will reduce their damage potential by causing initial mortality, by reducing the amount of plant material consumed by the surviving grasshoppers, and by preventing grasshopper maturation and reproduction (at higher doses). The negative influence of entomopoxvirus on grasshoppers in the interim between infection and death is integral to future evaluations of its potential as a crop protection measure.

ISSN:1754-5692    

DOI:10.1093/ee/20.6.1720

出版商:Oxford University Press    

年代:1991

数据来源: OUP

摘要:

Penicillaria jocosatrixGuenée consumes new leaves, flowers, and fruits of mango and has been a serious pest on Guam. Before 1986, few natural enemies were present and there were no parasitoids attacking the larvae. In 1986, a program was initiated to introduce larval parasitoids. The waspsAleiodessp. andEuplectrussp. and thefly Blepharella lateralisMacquart were released.Aleiodessp. did not establish, butEuplectrussp. andB. lateralisdid. Populations of the mango shoot caterpillar fell to 25% of their prerelease levels. Parasitization rates ranged from 20 to 99%.Euplectrussp. was the most abundant parasitoid. It parasitized all instars, but was more common on second and third instars. More eggs were laid on older instars of the caterpillar.Euplectrussp. was more abundant in the dry season whereasB. lateraliswas more common in the wet season. Fruit production on monitored trees increased significantly after the parasitoids became effective.

ISSN:1754-5692    

DOI:10.1093/ee/20.6.1725

出版商:Oxford University Press    

年代:1991

数据来源: OUP

摘要:

Parasitization rates of eggs of oriental fruit fly,Dacus dorsalisHendel, byBiosteres arisanus(Sonan), and larvae of melon fly,Dacus cucurbitaeCoquillett. byPsytallia fletcheri(Silvestri) in mature green to fully ripe papaya fruits on trees and in fully ripe fruits on the ground was studied. Parasitization of oriental fruit fly eggs byB. arisanuswas greater in fully ripe fruits than in one-quarter to half-ripe fruits on trees;B. arisanusnever parasitized oriental fruit fly eggs in mature green to color-break fruits. No difference was observed in the density of emergentB. arisanusadults from oriental fruit fly pupae recovered from fully ripe fruits on trees and on the ground. Parasitization of melon fly larvae byP. fletcheriwas observed in only one fully ripe, fallen fruit. Results in relation to the effect of host plants on the foraging behavior of adult parasitoids and to the biological control of oriental fruit fly and melon fly in an agricultural ecosystem were discussed.

ISSN:1754-5692    

DOI:10.1093/ee/20.6.1732

出版商:Oxford University Press    

年代:1991

数据来源: OUP

ISSN:1754-5692    

DOI:10.1093/ee/20.6.1737

出版商:Oxford University Press    

年代:1991

数据来源: OUP

ISSN:1754-5692    

DOI:10.1093/ee/20.6.1738

出版商:Oxford University Press    

年代:1991

数据来源: OUP

ISSN:1754-5692    

DOI:10.1093/ee/20.6.1739

出版商:Oxford University Press    

年代:1991

数据来源: OUP

ISSN:1754-5692    

DOI:10.1093/ee/20.6.1741

出版商:Oxford University Press    

年代:1991

数据来源: OUP

ISSN:1754-5692    

DOI:10.1093/ee/20.6.1745

出版商:Oxford University Press    

年代:1991

数据来源: OUP

ISSN:1754-5692    

DOI:10.1093/ee/20.6.1747

出版商:Oxford University Press    

年代:1991

数据来源: OUP