Project description:Global warming substantially changes precipitation patterns in the Tibetan plateau, with projection of increased precipitation in southern and northern Tibet but decreased precipitation in the center. Understanding mechanisms of such changes in greenhouse gas emissions is of vital importance in predicting ecosystem feedbacks to climate changes. Nonetheless, it has been hampered by limited knowledge in soil microbial communities, one of the major drivers of greenhouse gas emission. Here, we report a field experiment simulating drying and wetting conditions in the Tibetan grassland. Our field site is located at the Haibei Alpine Grassland Ecosystem Research Station in the northeast of Tibet Plateau, China, and we employed GeoChip 5.0 180K to analyze microbial responses.
Project description:Global warming substantially changes precipitation patterns in the Tibetan plateau, with projection of increased precipitation in southern and northern Tibet but decreased precipitation in the center. Understanding mechanisms of such changes in greenhouse gas emissions is of vital importance in predicting ecosystem feedbacks to climate changes. Nonetheless, it has been hampered by limited knowledge in soil microbial communities, one of the major drivers of greenhouse gas emission. Here, we report a field experiment simulating drying and wetting conditions in the Tibetan grassland. Our field site is located at the Haibei Alpine Grassland Ecosystem Research Station in the northeast of Tibet Plateau, China, and we employed GeoChip 5.0 180K to analyze microbial responses. 18 samples were collected from 3 plots in Haibei Station, with 6 replicates in each plot
Project description:Verticillium dahliae Kleb., a soil-borne fungus that colonizes vascular tissues, induces wilting, chlorosis and early senescence in potato. Difference in senescence timing found in two diploid potato clones, 07506-01 and 12120-03, was studied and genetic variation in response to V. dahliae infection was identified as a causal factor. The clone, 07506-01, was infected with V. dahliae but did not develop symptoms, indicating tolerance to the pathogen. The other diploid clone, 12120-03 had low levels of pathogen with infection and moderate symptoms indicating partial resistance. 07506-01 was found to carry two susceptible alleles of the Ve2 gene and 12120-03 carried one Ve2 resistant and one susceptible allele. Infected leaves of the two clones were compared using gene expression profiling with the Potato Oligonucleotide Chip Initiative (POCI) microrarray. The results provide further evidence for differences in response of the two clones to infection with V. dahliae. Chlorophyll biosynthesis was higher in the tolerant 07506-01 compared to partially resistant 12120-03. On the other hand, expression of fungal defense genes, Ve resistance genes and defense phytohormone biosynthetic enzyme genes was decreased in 07506-01 compared to 12120-03 suggesting defense responses were suppressed in tolerance compared to resistance. Transcription factor gene expression differences pointed to the WRKY family as potential regulators of V. dahliae responses in potato. Two-color microarray comparison of two clones, three biological replicates of each clone, one dye swap technical replicate