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Abstract: The aphid parasitoid Lysiphlebus testaceipes is a potentially valuable biological control agent of Aphis gossypii a major worldwide pest of cotton. One means of increasing the abundance of a biological control agent is to provide an alternative host habitat adjacent to cropping, from which they can provide pest control services in the crop. Host selection and parasitism rate of an alternative host aphid, Aphis craccivora by L. testaceipes were studied in a series of experiments that tested its host suitability relative to A. gossypii on cotton, hibiscus and mungbean. Host acceptance, as measured by number of ovipositions was much greater in A. craccivora compared to A. gossypii, while more host aphids were accepted on mungbean than cotton. When given a choice L. testaceipes attacks more 4th instar and adult stages (63% and 70%, respectively) of both hosts than 2nd instar nymphs (47%). In a switching (host choice) experiment, L. testaceipes preferentially attacked A. craccivora on mungbean over A. gossypii on cotton. Observations of parasitoid contact with A. gossypii cornicle secretion suggest it provides a useful deterrent against parasitoid attack. From these experiments it appears L. testaceipes has a preference for A. craccivora and mungbean compared to A. gossypii and cotton, in this respect using A. craccivora and mungbean as alternative habitat may not work as the parasitoid is unlikely to switch away from its preferred host. [Copyright &y& Elsevier]

Abstract: The use of artificial food sprays to increase the abundance and impact of natural enemies of arthropod pests has been recognized for over 40 years. Nevertheless, artificial food sprays are applied in relatively few conservation biological control programs, possibly because of inconsistent performance. To consider this explanation, using a hierarchical classification approach ranging from altered foraging behavior at the simplest level to profitability of farm production at the highest level, we quantitatively reviewed 234 trials from 77 publications. The levels of assessment of food sprays most commonly found in the publications were the densities of arthropod pests (59 trials) and their natural enemies (124). Although the density of natural enemies increased in 108 of the 124 trials (or 87% of cases) and pest populations declined in 28 of the 59 trials (or 47%), increased profit was not demonstrated in the five trials where it was examined. The most commonly studied natural enemies belonged to the order Neuroptera (104 trials). Nevertheless, the parasitic Hymenoptera had the highest proportion of positive successes (56 of the 69 trials or 81%). Contrary to predictions, the likelihood of a successful result was not affected by the duration of food spray provision, management intensity, application frequency, or replenishment interval. However, success was more likely as spray concentration increased. When analyzed separately, the Coleoptera showed the greatest response to carbohydrates alone, such as honey and sucrose, compared with a mixture of carbohydrates and proteins. To achieve greater success with artificial food sprays, and therefore overcome a major impediment to their adoption, we contend that researchers should: (i) demonstrate greater success across several levels in the hierarchy, especially profit; (ii) consistently demonstrate success in field trials replicated across regions and years; and (iii) combine artificial food sprays with other compatible elements of an integrated pest management strategy. Until these outcomes are demonstrated, it is envisaged that artificial food sprays will form only a small part of future conservation biological control programs. [Copyright &y& Elsevier]

The minute two-spotted ladybeetle, Diomus notescens Blackburn is a common predator of aphids and other pests in Australian agricultural crops, however little is known about the biology of D. notescens . The aim of this study was to provide information on the life cycle of this predator and improve our understanding of its biological control potential, particularly against one of the major pests of cotton, Aphis gossypii Glover. In laboratory experiments, juvenile development, prey consumption, as well as adult lifespan and fecundity were studied. Results from this study revealed that D. notescens could successfully complete development on A. gossypii , which at 25 °C required 21 days and during this period they each consume 129 ± 5.2 aphids. At 25 °C adult lifespan was 77 ± 9.6 days, with a mean daily prey consumption of 28 ± 1.8 aphids and a mean daily fecundity of 8 ± 0.5 eggs. Net reproductive rate was estimated as 187 ± 25.1 females and the intrinsic rate of increase was estimated as 0.14. Juvenile development was recorded at four constant temperatures (15, 21, 26 and 27 °C) and using a linear model, the lower threshold for D. notescens development was estimated to be 10 ± 0.6 °C with 285 ± 4.7 degree days required to complete development. A prey choice experiment studying predation rates revealed a strong preference for A. gossypii nymphs compared to Bemisia tabaci Gennadius eggs. [ABSTRACT FROM AUTHOR]

Highlights: [•] Natural enemies of insect pests in brassica vegetable crops are numerous in China. [•] Major parasitoids have great potential to suppress pest populations. [•] The role of natural enemies can be promoted by the use of selective insecticides. [•] The strategy of conservation biological control can reduce insecticide input. [•] Several successful brassica IPM practices have enhanced conservation biological control. [ABSTRACT FROM AUTHOR]

Parthenium weed plants grown under two atmospheric CO 2 concentrations, with and without the biological control agent Epiblema strenuana. • Parthenium weed had significantly enhanced growth under an atmosphere enriched with CO 2. • Epiblemma strenuana retained its efficacy in managing parthenium weed under elevated [CO 2 ]. • E. strenuana significantly reduced weed seed production and fill regardless of [CO 2 ]. Parthenium hysterophorus (Parthenium weed) is a highly invasive species that has become a major weed in Australia and many other parts of the world. The present study reports on the effect of atmospheric CO 2 enrichment upon the performance and effectiveness of one of its biological control agents, Epiblema strenuana (stem-galling moth). Parthenium weed plants, when grown under an elevated CO 2 concentration (550 µmol mol−1), produced a significantly greater dry biomass (38%), produced more branches (35%) and seeds per plant (37%), than plants grown under an ambient CO 2 concentration (380 µmol mol−1). Galls produced by E. strenuana significantly reduced the height (46%) and dry biomass (45%) of parthenium weed under the elevated CO 2 concentration. In the presence of E. strenuana , the total number of cypselae produced by plants was 60 or 32% less at ambient or elevated CO 2 concentrations, respectively. X-ray revealed that E. strenuana had a significant negative impact upon cypsela fill under elevated CO 2 concentration with about 50% not being filled. Gall induction by E. strenuana stimulated lateral branching and this was observed in plants grown both under elevated and ambient CO 2 concentrations. Under elevated CO 2 and in the presence of E. strenuana , net photosynthesis and water use efficiency were decreased by 25 and 28%, respectively. Despite parthenium weed producing more biomass and seed, this study indicates that the efficacy of E. strenuana as a biological control agent of parthenium weed is likely to be retained in a future climate with an elevated CO 2 concentration. [ABSTRACT FROM AUTHOR]

Highlights: [•] We report Trichogramma chilonis Ishii parasitizing Crocidolomia pavonana F. in Samoa. [•] This is the first record of T. chilonis in Samoa. [•] It is widely established and can significantly suppress C. pavonana populations. [•] The parasitoid has significant potential for biological control of C. pavonana elsewhere. [ABSTRACT FROM AUTHOR]

Abstract: Understanding the effects of different types and quality of data on bioclimatic modeling predictions is vital to ascertaining the value of existing models, and to improving future models. Bioclimatic models were constructed using the CLIMEX program, using different data types – seasonal dynamics, geographic (overseas) distribution, and a combination of the two – for two biological control agents for the major weed Lantana camara L. in Australia. The models for one agent, Teleonemia scrupulosa Stål (Hemiptera: Tingidae) were based on a higher quality and quantity of data than the models for the other agent, Octotoma scabripennis Guérin-Méneville (Coleoptera: Chrysomelidae). Predictions of the geographic distribution for Australia showed that T. scrupulosa models exhibited greater accuracy with a progressive improvement from seasonal dynamics data, to the model based on overseas distribution, and finally the model combining the two data types. In contrast, O. scabripennis models were of low accuracy, and showed no clear trends across the various model types. These case studies demonstrate the importance of high quality data for developing models, and of supplementing distributional data with species seasonal dynamics data wherever possible. Seasonal dynamics data allows the modeller to focus on the species response to climatic trends, while distributional data enables easier fitting of stress parameters by restricting the species envelope to the described distribution. It is apparent that CLIMEX models based on low quality seasonal dynamics data, together with a small quantity of distributional data, are of minimal value in predicting the spatial extent of species distribution. [Copyright &y& Elsevier]

• P. persimilis showed fine life history traits on the susceptible cucumber cultivar. • The resistant cultivar supported more P. persimilis to have higher predation. • Combination of resistant cucumber cultivar and P. persimilis is offered against TSSM. Tritrophic interactions can provide important insights for improving the efficacy of pest control programs. We studied three cucumber, Cucumis sativus , cultivars for their effects on the life table and predation parameters of the predatory mite, Phytoseiulus persimilis Athias–Henriot, when feeding on eggs and nymphs of the two-spotted spider mite (TSSM), Tetranychus urticae Koch. These cultivars were TSSM-susceptible (cv. Vida), semi-resistant (cv. Sultan), and resistant (cv. Caspian). Under laboratory conditions, the intrinsic rate of increase (r) and net reproductive rate (R 0) of P. persimilis was significantly higher on the susceptible cultivar than on the resistant ones. In contrast, the age-stage-specific predation rate (c xj), net predation rate (c 0) and finite predation rate on the resistant cultivar were all higher than on the semi-resistant or susceptible ones. Although the susceptible cultivar produced the most favorable life table parameters for P. persimilis , the resistant cultivar supported more P. persimilis individuals and had higher levels of predation on TSSM. Resistant cultivars in combination with P. persimilis can improve control of TSSM on cucumber, despite some negative life history impacts on the predator. [ABSTRACT FROM AUTHOR]