We studied the effects of landscape structure, habitat loss and fragmentation on genetic differentiation of Moor frog populations in two landscapes in The Netherlands (Drenthe and Noord-Brabant). Microsatellite data of eight loci showed small to moderate genetic differentiation among populations in both landscapes (F ST values 0.022 and 0.060, respectively). Both heterozygosity and population differentiation indicate a lower level of gene flow among populations in Noord-Brabant, where populations were further apart and have experienced a higher degree of fragmentation for a longer period of time as compared to populations in Drenthe. A significant isolation-by-distance pattern was found in Drenthe, indicating a limitation in dispersal among populations due to geographic distance. In Noord-Brabant a similar positive correlation was obtained only after the exclusion of a single long-time isolated population. After randomised exclusion of populations a significant additional negative effect of roads was found but not of other landscape elements. These results are discussed in view of improving methodology of assessing the effects of landscape elements on connectivity.

Background: Bet v 1 is an important cause of hay fever in northern Europe. Bet v 1 isoforms from the European white birch (Betula pendula) have been investigated extensively, but the allergenic potency of other birch species is unknown. The presence of Bet v 1 and closely related PR-10 genes in the genome was established by amplification and sequencing of alleles from eight birch species that represent the four subgenera within the genus Betula. Q-TOF LC-MS E was applied to identify which PR-10/Bet v 1 genes are actually expressed in pollen and to determine the relative abundances of individual isoforms in the pollen proteome.

Wild relatives of tomato possess effective means to deal with several pests, among which are a variety of insects. Here we studied the presence of resistance components against Trialeurodes vaporariorum, Myzus persicae, Frankliniella occidentalis, and Spodoptera exigua in the Lycopersicon group of Solanum section Lycopersicon by means of bioassays and comprehensive metabolite profiling. Broad spectrum resistance was found in Solanum galapagense and a few accessions of S. pimpinellifolium. Resistance to the sap sucking insects may be based on the same mechanism, but different from the caterpillar resistance. Large and highly significant differences in the leaf metabolomes were found between S. galapagense, containing type IV trichomes, and its closest relative S. cheesmaniae, which lacks type IV trichomes. The most evident differences were the relatively high levels of different methylated forms of the flavonoid myricetin and many acyl sucrose structures in S. galapagense. Possible candidate genes regulating the production of these compounds were identified in the Wf-1 QTL region of S. galapagense, which was previously shown to confer resistance to the whitefly B. tabaci. The broad spectrum insect resistance identified in S. galapagense will be very useful to increase resistance in cultivated tomato.