Plants producing pyrrolizidine alkaloids: sustainable tools for nematode management?

1,2-dehydropyrrolizidine ester alkaloids (pyrrolizidine alkaloids; PAs) are a class of secondary plant metabolites found in hundreds of plant species. In vitro, PAs are known to affect plant-parasitic nematodes. Thus, PA-producing plants might be used in nematode management. So far, however, Crotalaria is the only PA-producing plant that has been used for nematode control. Consequently, we reviewed the literature on other PA plants and their effects on nematodes. This included the analysis of in vitro experiments with PA plant extracts, host tests with PA plants, as well as experiments in which PA-producing plants were used as different types of soil amendments (mulch, in situ mulching, extracts). Our results clearly show that, in addition to Crotalaria, certain other PA-producing plant species have the potential to be used in sustainable nematode management. This is especially true for management of sedentary endoparasitic nematode species. Promising applications include the use of PA plant extracts and mulches, as well as the use of PA plants for in situ mulching

Asian Honey Bee Apis cerana foraging on mushrooms

Honey bees (Apis spp.) are well known for obtaining their nutrition from pollen and nectar collected from a wide range of flowers (Winston, 1991). They also collect honeydew secreted by aphids and scale insects as an additional source of carbohydrate. Many species of bees use plant resins, which when mixed with their saliva produces propolis, a sticky substance used to seal the hive and help combat pathogens and infections (Castro, 2001). In some honey bees e.g. Apis florea propolis can be used as an ant deterrent (Duangphakdee, Koeniger, Koeniger, Wongsiri, & Deowanish, 2005). However, in Brazil the Africanized honey bee (Apis mellifera) workers gather mycelium and spores from Cladosporium sp. of fungi (Modro, Silva, & Luz, 2009) but are not known to visit the fruiting body of fungi. Here we report for the first-time honey bee (A. mellifera) workers apparently feeding on the fruiting body of fungi

Semiochemicals derived from pyrrolizidine alkaloids in male ithomiine butterflies (Lepidoptera : Nymphalidae : Ithomiinae)

Analysis of male hairpencil components of 54 species in 30 genera of Ithomiinae, butterflies showed the presence of 13 volatile compounds formed by hydrolysis, oxidation, lactonization and/or methylation of both necic acid and pyrrolizidine base portions of lycopsamine, an alkaloid widespread in nature and known to be specifically sought, ingested and stored by these insects. Six of these compounds have not been reported before from insects. Comparison of occurrence of components with proposed phylogenies of the 50 or more genera in the subfamily did not give clear patterns, though simpler derivatives well known in other Lepidoptera occurred throughout the subfamily, while more specific structures, including a lactone resulting from specific oxidation of an unactivated methyl group, were more typical of apomorphic genera. (C) 2004 Elsevier Ltd. All rights reserved.32869971