查看更多>>摘要：Sugar flotation procedures have been used for many years to separate insects from soil and other substrates. In this study we investigated whether brown sugar flotation (BSF) could be used for detecting eggs and larvae of Bactrocera tryoni (Froggatt) and Ceratitis capitata (Wiedemann) in cherries. Our first study involved both species and combined BSF with either manually or mechanically crushed fruit to quantify the egg and larval detection ability of BSF in conjunction with these sample preparation methods. A second set of experiments (using B. tryoni only) focused on determining the sensitivity of BSF for detecting fruit fly infestation and determining the proportions of different life stages recoverable. This was done by varying oviposition periods to generate fruits with different infestation levels. Our final experiments were used to develop an optimized cherry fruit sampling regime for detecting B. tryoni using BSF. Wet sieving/maceration of the fruit residue and incubation of the macerated fruit sample to allow further insect development were used to determine the number of eggs and larvae in each test sample that were not detected using BSF. Our results show that BSF is more effective when combined with mechanical (rather than manual) fruit crushing. BSF is highly sensitive, detecting at least one B. tryoni second instar from all the samples tested down to a pest density of 1-5 larvae in one fruit within a 35-fruit sample. BSF was less sensitive for egg detection, however when 6 or more eggs were present within a sample of 35 fruits, the probability of detecting at least one egg was >= 85%. Samples of 35 or 42 cherries provided a higher probability of detecting B. tryoni than larger samples when 1-5 eggs or larvae were present in total. BSF is an effective tool for detecting the presence of fruit fly eggs and particularly larvae in cherries and should be considered for incorporation into the current market access protocol for minimizing fruit fly risk in Australian cherry exports.
Teixeira, Cristiano MachadoKruger, Alexandra PeterNava, Dori EdsonMello Garcia, Flavio Roberto...
8页
查看更多>>摘要：The current distribution of Anastrepha grandis, South American cucurbit fruit fly, under current climate conditions is restricted to South and Central America. However, this species is considered a quarantine pest and its presence in fruits is highly unwanted in exports, mainly to territories that offer conditions for their establishment. According to recent studies, changes in climate conditions may contribute to a range expansion due to the reduction of cold-induced stress, which still prevents the colonization of many areas. By predictive modeling, this study aimed to answer the question regarding the potential distribution of the South American cucurbit fruit fly under climate change, using two global circulation models - HadGEM2-ES and Miroc5 - in four change scenarios representing simulations of radiative force at 2.6 W.m-2, 4.5 W.m-2, 6 W.m-2, and 8.5 W.m-2 for the years of 2050 and 2070. All tested scenarios supply environmental suitability conditions for the establishment of the fly in other continents, especially in regions of central Africa, Southeast Asia, and Australasian territories. Furthermore, areas of medium and low suitability predicted in all future scenarios are larger than current metrics and the fly will benefit from climate change, as environmental suitability areas move forward towards the poles.
查看更多>>摘要：Afidopyropen is a novel pyropene insecticide that has been shown to be effective for the management of Aphis gossypii Glover. Establishing the susceptibility baseline of A. gossypii to this newly commercialized insecticide is important for ensuring its continued efficacy. The aim of this study was to evaluate the susceptibility baseline of field populations of A. gossypii to the novel insecticide afidopyropen. A total of 25 field populations of A. gossypii were collected in China from 2019 to 2020, and the susceptibility of these populations to afidopyropen was determined in the laboratory using a leaf-dipping method. The results indicated that afidopyropen was highly toxic to adult A. gossypii, and the LC50 values ranged from 0.009 mg L-1 to 0.435 mg L-1, suggesting that afidopyropen is effective for controlling A. gossypii. Interestingly, we found that A. gossypii collected from cotton plants showed higher tolerance to afidopyropen compared with individuals collected from the other host plants. The findings of our study will aid future efforts to monitor A. gossypii resistance to afidopyropen.
NSTL
Elsevier