BACKGROUND: Thiophanate-methyl, a member of the benzimidazole class of fungicides, is used in California to control brown rot of stone fruit caused by Monilinia fructicola (G. Wint.) Honey. The goal of this study was to develop a real-time polymerase chain reaction (PCR) assay as an efficient method to quantify the E198A allele of beta-tubulin that confers benzimidazole resistance. RESULTS: Using the real-time PCR assay, the frequency of allele E198A (FEA) in a population was determined from the quantities of DNA amplified with the E198A allele-specific primer pair HRF/HRR and the M. fructicola-specific primer pair MfF6/MfR6. The average proportions of highly resistant isolates determined with the conventional fungicide sensitivity method were within the range of average FEA values determined with the real-time PCR assay. We also determined the FEAs of M. fructicola populations sampled from 21 stone fruit orchards in California. Only one orchard showed a high FEA over 0.20, seven orchards had values between 0.01 and 0.1, and 13 orchards had values less than 0.01. CONCLUSION: The real-time PCR assay developed in this study provides a potentially useful tool to efficiently quantify benzimidazole resistance for large M. fructicola populations. 相似文献
Low winter temperatures severely stress newly arriving insect species. Adaptive evolutionary changes in cold tolerance can facilitate their establishment in new environments. Ambrosia artemisiifolia, a noxious invasive plant, occurs throughout China. Ophraella communa, a biological control agent of A. artemisiifolia, mainly occurs in southern China. However, in 2012, it established populations in Beijing (39.98°N, 115.97°E) following introduction from Laibin (23.62°N, 109.37°E), implying cold adaptation. The mechanisms underlying its rapid evolution of cold tolerance remain unknown. We investigated the levels of cryoprotectants and energy reserves in adult O. communa from two latitudes. In high-latitude insects, we found high trehalose, proline, glycerol, total sugar, and lipid levels; five potential genes (Tret1a, Tret1b, Tret1-2, P5CS, and GST), responsible for regulating cold tolerance and involved in trehalose transport, proline biosynthesis, and glutathione S-transferase activation, were highly expressed. These hybridisation changes could facilitate cold temperature adaptation. We demonstrate the genetic basis underlying rapid adaptation of cold tolerance in O. communa, explaining its extension to higher latitudes. Thus, specialist herbivores can follow host plants by adapting to new temperature environments via rapid genetic evolution.
New Forests - Forest tree seedling production technologies impact reforestation success determined with survival and quality of seedlings. Five Abies alba seedling production technologies were... 相似文献
European Journal of Forest Research - The resistance of different genotypes to abiotic stress may be due to genetic effects and/or to phenotypic plasticity allowing them to acclimate to variable... 相似文献