Two hundred and forty isolates of Botrytis cinerea were collected during the early summer of 2012 and 2013 from strawberry greenhouses in 10 locations in Hubei Province and examined for sensitivity to five fungicides, most of which were commonly used to control this fungus. High frequency of resistance to carbendazim (Car, 63.63%) and cyprodinil (Cyp, 42.42%) was detected. Boscalid-resistant (BosR) isolates were detected for the first time in China, whereas no fludioxonil-resistant isolates were identified. Dual resistance to carbendazim and diethofencarb (Die) was also detected. There were six phenotypes of resistance profile (i.e., CarRDieSBosSCypS, CarRDieRBosSCypS, CarRDieSBosSCypR, CarRDieSBosRCypS, CarRDieRBosSCypR, and CarRDieSBosRCypR). CarRDieSBosSCypS and CarRDieSBosSCypR were the most common phenotypes, occurring at eight and seven locations, respectively. After 10 successive transfers on fungicide-free potato dextrose agar, tested resistant isolates retained levels of resistance similar to or comparative with the initial generation, indicating the stability of these resistances. Fitness evaluations based on investigation of mycelial growth, osmotic sensitivity, sporulation in vitro and in vivo, and virulence revealed the uncompromising fitness in resistant isolates, except that decreased virulence was observed in BosR isolates. The molecular basis of carbendazim, diethofencarb, and boscalid resistance was investigated. Results showed that all 13 sequenced carbendazim-resistant isolates harbored the mutation E198V or E198A in the β-tubulin gene and the five isolates with dual resistance to carbendazim and diethofencarb showed the mutation E198K in the same gene. BosR isolates possessed the H272R mutation in succinate dehydrogenase subunit B gene. The results achieved in this study challenge the current management strategies for B. cinerea, which largely depend on applications of these fungicides.

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The Japanese pine sawyer, Monochamus alternatus Hope (Coleoptera: Cerambycidae), is a major pest of pines and it is also the key vector of the exotic pinewood nematode in China. In the present study, we cloned, expressed, and purified a chemosensory protein (CSP) in M. alternatus. We surveyed its expression in various developmental stages of male and female adult tissues and determined its binding affinities for different pine volatiles using a competitive binding fluorescence assay. A CSP known as CSP5 in M. alternatus was obtained from an antennal cDNA library and expressed in Escherichia coli. Quantitative reverse transcription polymerase chain reaction results indicated that the CSP5 gene was mainly expressed in male and female antennae. Competitive binding assays were performed to test the binding affinity of recombinant CSP5 to 13 odour molecules of pine volatiles. The results showed that CSP5 showed very strong binding abilities to myrcene, (+)-β-pinene, and (-)-isolongifolene, whereas the volatiles 2-methoxy-4-vinylphenol, p-cymene, and (+)-limonene oxide have relatively weak binding affinity at pH 5.0. Three volatiles myrcene, (+)-β-pinene, and (-)-isolongifolene may play crucial roles in CSP5 binding with ligands but this needs further study for confirmation. The sensitivity of insect to host plant volatiles can effectively be used to control and monitor the population through mass trapping as part of integrated pest management programs.

Odorant-binding proteins (OBPs) are believed to play an important role in olfactory recognition. In this study, expression pattern and fluorescence binding characteristics of MaltOBP13 from the Japanese pine sawyer beetle, Monochamus alternatus Hope, were investigated via qPCR analysis of MaltOBP13 mRNA level and binding assay of MaltOBP13 and ligands. qPCR monitoring indicated MaltOBP13 mainly expressed in newly emerged males, particularly highly expressed in the last abdominal segment of males, and the expression level was significantly higher in 13day-old mated adults than those of other stages. To further understand the function of the MaltOBP13 protein in odorant reception, the binding affinity of recombinant MaltOBP13 to ligands was tested by fluorescence binding assays with N-phenyl-1-naphthylamine as a fluorescent probe. The results of this assay indicated that MaltOBP13 exhibited a high binding affinity for pine volatiles and binding capacity was higher in acidic conditions than in neutral environment, indicating a possible role in finding host plants.

Bank GU596416; and CPBF 1171, GenBank GU596419) were compared by nucleotide blast at NCBI and displayed higher levels of DNA similarity (>98%) to NCPPB 1946, the type strain for Xcr, than to NCPPB 528, the type strain for Xcc. The polyphasic approach combining phenotypic and genomic data confirmed the presence of X. campestris pv. raphani in Portugal for the first time.