Project description:Coumaphos is an acaricide that is widely used to control Varroa mites in bee colonies. However, the extensive use of coumaphos against Varroa has resulted in the development of coumaphos resistant Varroa populations. In this study, the whole genome gene expression profile of 1) a coumaphos resistant V. destructor population (AN-CR) or 2) a coumaphos resistant V. destructor population pretreated with coumaphos (tAN-CR), was compared to the gene expression profile of a susceptible V. destructor population (ATH-S) using Illumina RNAseq.
Project description:To study the underlying molecular mechanisms during the Varroa destructor life cycle, we carried out transcriptomic profiling of seven stages: young mites (collected from P8 to P9 brood cells), phoretic mites (collected on adult bees), arresting mites (collected in unsealed L5 brood cells), pre-laying mites (collected from sealed brood cells containing moving larva), laying mites (collected from sealed brood cells containing pre-pupae), post-laying mites (collected from capped brood cells containing purple-eye and white-body pupae P5), emerging mites (collected from P8 to P9 brood cells). In addition, we sampled non-reproducing mites (collected from P5 brood cells, but without offspring), males (collected from P8 to P9 brood cells), and phoretic mites artificially reared in cages with adult bees. This study was performed using Apis mellifera L. honey bee colonies naturally infested by Varroa destructor mites. Adult mites were collected from 4 unrelated colonies.
Project description:Maize is one of the most important crops in the world. Heilongjiang province has the largest maize area in China. Plant-parasitic nematodes are important agricultural pests, which cause huge economic losses every year and have attracted global attention. Potato rot nematode Ditylenchus destructor is a plant-parasitic nematode with a wide range of hosts and strong survival ability in different environments, which brings risks to agricultural production. In 2020, D. destructor was detected in seven maize fields in Heilongjiang province. Morphological identification and molecular approach were used to characterize the isolated D. destructor. The observed morphological and morphometric characteristics were highly similar and consistent with the existing description. The DNA sequencing on the D2/D3 region of the ribosomal DNA 28S and the phylogenetic analysis showed that D. destructor population obtained from maize and other isolates infesting carrot, sweet potato, and potato were in subclade I supported by a 96% bootstrap value. Additionally, the phylogenetic analysis of the ITS rRNA gene sequence further indicated that this D. destructor population from maize clustered in a clade I group and belonged to ITS rRNA haplotype C. An inoculation experiment revealed that D. destructor was pathogenic on the maize seedlings in pots and caused the disease symptoms in the stem base of maize seedlings. This is the first report of D. destructor causing stem rot of maize in Heilongjiang province, and contributes additional information on disease control and safe production of maize in the region.