the 337 isolates collected, the overall gene diversity was moderate ( = 0.216). The level of multilocus genotypic diversity was higher within populations than among them. All individuals had unique multilocus genotypes. Genetic differentiation was significant among populations in localities, but at a moderate level (θ = 0.12; P < 0.001), suggesting that gene flow is occurring among populations. The isolates from all twelve clusters produced by Structure were found in all local populations, although at different frequencies. Therefore, the inferred clusters did not represent geographical populations. Although the null hypothesis of random mating in Rcc populations was rejected, the high level of genotypic diversity suggests that the Rcc population structure appears to be generated by a
mixed reproductive system including both asexual and sexual reproduction, along with a rather high migration rate. “
“Sensitivity monitoring studies BMS-907351 mw using detached leaf tests with isolates of Podosphaera leucotricha showed no adaptation to pyraclostrobin in the last years. Sequence analysis of the target ZVADFMK gene of QoIs, cytochrome b, of different isolates of P. leucotricha showed the presence of an intron directly after codon 143. This makes the occurrence of the G143A mutation unlikely. On the other hand, intron sequences have not been detected in immediate vicinity to the codons 129 and 137; therefore, the occurrence of those two mutations cannot be excluded. As the effects of these mutations on field performance Mannose-binding protein-associated serine protease on QoI fungicides are rather low, the overall resistance risk of P. leucotricha to this
fungicide class is estimated to be low. The amplified cytochrome b gene fragments (exons and introns) for samples from different European countries and Australia were highly conserved. “
“Groundnut is commonly consumed in its roasted form by many Nigerians. This study was therefore conducted to determine the levels of aflatoxin in roasted groundnut retailed in south-western Nigeria with a view to assessing the fitness of the processed nut for human consumption. The effects of roasting and de-coating as alternative methods for reducing the ‘aflatoxin scare’ in the nut were further assessed on aflatoxigenic fungal load and aflatoxin content of the nuts. Forty-eight samples of retailed raw and roasted groundnut were collected and assessed by mycological and thin-layer chromatographic analysis for changes in aflatoxigenic fungal population and aflatoxin concentration, respectively. Consequently, 480 isolates of the Aspergillus section Flavi group, A. flavus L strain (n = 410), A. tamarii (n = 56), A. parasiticus (n = 7) and A. parvisclerotigenus (n = 7), were recovered from all samples. Aflatoxigenic isolates of A. flavus L strain (58.8%) had a significantly (P < 0.05) higher incidence than the non-aflatoxigenic isolates (41.2%). Aflatoxins were detected in 43 (89.