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Olive fruit fly Bactrocera oleae (Rossi) (Diptera: Tephritidae) is a major olive pest in the Mediterranean basin where increasing insecticide resistance has enhanced damage and necessitates more reliance on other control strategies, such as biological control. Provision of floral resources has been reported to improve the effectiveness of natural enemies. Here, we tested the effect of six plant nectars and two honeydew sources on the survival of Psyttalia concolor (Szépligeti) (Hymenoptera: Braconidae), a parasitoid wasp used in the biological control of olive fruit fly. Our results showed a positive effect on survival associated with nectars of Anchusa azurea Mill., Rosmarinus officinalis L., Lavatera cretica L. and Calamintha nepeta (L.) Savi, while honeydew proved to be a valuable alternative food source. When offering flowers directly to insects, Anchusa azurea, Lavatera cretica, and Foeniculum vulgare L. were found to be the most beneficial species, indicating also that P. concolor feeds predominantly on shallow corollas. [ABSTRACT FROM AUTHOR]

Background and Aims: Phenolic compounds influence colour, flavour and astringency of wines. Technology and grape variety are the main factor affecting the phenolic content of wines. Different multivariate statistical approaches were used to investigate the relationships between the profile of phenolic compounds and grape variety and also the impact of malolactic fermentation (MLF). Methods and Results: A reversed phase liquid chromatography/diode array detection method was used for the analysis of major non-flavonoid phenolic compounds in wines from Trincadeira, Aragonez, Cabernet Sauvignon, Alfrocheiro, Casteão and Touriga Nacional varieties before and after MLF. The impact of MLF and grape variety on phenolic profile was evaluated by principal component analysis (PCA), variation partitioning analysis (VPA) and artificial neural network (ANN). PCA explained 86.5% of the total variance among samples. ANN showed a significant clustering of samples according to grape variety and confirmed that MLF has a minor effect on wine phenolic profile. VPA enabled more information to be extracted from the data by identifying explanatory variables responsible for variability among samples. Conclusions: Compared with PCA and ANN, VPA provides more information concerning the variability on the sample system. Also, grape varieties have a more effective impact on wine low molecular weight phenolic compounds than MLF. Significance of the Study: Each one of the three multivariate statistical approaches showed ways of analysing large chemistry experimental datasets. VPA is a step forward in data analysis, providing more solid and complete assessment of sample system variability, not possible by PCA and ANN. [ABSTRACT FROM AUTHOR]