Project description:Bacterial wilt caused by Ralstonia solanacearum is a lethal, soil-borne disease of tomato. Control of the disease with chemicals and crop rotation is insufficient, because the pathogen is particularly well adapted for surviving in the soil and rhizosphere. Therefore, cultivar resistance is the most effective means for controlling bacterial wilt, but the molecular mechanisms of resistance responses remain unclear. We used microarrays to obtain the characteristics of the gene expression changes that are induced by R. solanacearum infection in resistant cultivar LS-89 and susceptible cultivar Ponderosa.
2012-10-06 | GSE31807 | GEO
Project description:Crop rotation selects for distinct core microbiota
Project description:Soil microbial community is a complex blackbox that requires a multi-conceptual approach (Hultman et al., 2015; Bastida et al., 2016). Most methods focus on evaluating total microbial community and fail to determine its active fraction (Blagodatskaya & Kuzyakov 2013). This issue has ecological consequences since the behavior of the active community is more important (or even essential) and can be different to that of the total community. The sensitivity of the active microbial community can be considered as a biological mechanism that regulates the functional responses of soil against direct (i.e. forest management) and indirect (i.e. climate change) human-induced alterations. Indeed, it has been highglihted that the diversity of the active community (analyzed by metaproteomics) is more connected to soil functionality than the that of the total community (analyzed by 16S rRNA gene and ITS sequencing) (Bastida et al., 2016). Recently, the increasing application of soil metaproteomics is providing unprecedented, in-depth characterisation of the composition and functionality of active microbial communities and overall, allowing deeper insights into terrestrial microbial ecology (Chourey et al., 2012; Bastida et al., 2015, 2016; Keiblinger et al., 2016). Here, we predict the responsiveness of the soil microbial community to forest management in a climate change scenario. Particularly, we aim: i) to evaluate the impacts of 6-years of induced drought on the diversity, biomass and activity of the microbial community in a semiarid forest ecocosystem; and ii) to discriminate if forest management (thinning) influences the resistance of the microbial community against induced drought. Furthermore, we aim to ascertain if the functional diversity of each phylum is a trait that can be used to predict changes in microbial abundance and ecosystem functioning.
Project description:The soilborne fungus, Verticillium dahliae, causes Verticillium wilt disease in plants. Verticillium wilt is difficult to control since V. dahliae is capable of persisting in the soil for 10 to15 years as melanized microsclerotia, rendering crop rotation strategies for disease control ineffective. Microsclerotia of V. dahliae overwinter and germinate to produce infectious hyphae that give rise to primary infections. Consequentially, microsclerotia formation, maintenance, and germination are critically important processes in the disease cycle of V. dahliae.
Project description:One of the serious constraints to realize high level of rice crop productivity in Indian agriculture has been due to soil moisture stress (SMS) situation that growing plants often face. In order to increase or maintain the crop productivity in SMS situation our initial aim is to understand the drought response mechanism in different genotypes of rice. For thorough analysis of SMS situation in rice we have taken here two wild genotypes of rice namely Oryza nivara, Oryza rufipogan and three Indian cultivar namely Oryza Nagina-22, Oryza IR20 and Oryza Vandana, where IR20 is known to be susceptible and Vandana is known to be tolerant under SMS condition. Global analysis of transcript profiling under SMS condition reveal the actual picture of genes responsive to stress situation in different genetic background of rice. Furthermore it would help us in the selection of most desirable resource for crop breeding without compromising the yield of crop. We used the 44k rice Oligoarray from Agilent technologies to study the transcript profiling from five genotypes of rice under control, soil moisture stress and after recovery conditions during vegetative and grainfilling phase.Here in case of Nagina-22 we have taken grainfilling stage.
2016-04-01 | GSE49364 | GEO
Project description:soil microbiota during pea-wheat rotation
Project description:Bacterial wilt caused by Ralstonia solanacearum is a lethal, soil-borne disease of tomato. Control of the disease with chemicals and crop rotation is insufficient, because the pathogen is particularly well adapted for surviving in the soil and rhizosphere. Therefore, cultivar resistance is the most effective means for controlling bacterial wilt, but the molecular mechanisms of resistance responses remain unclear. We used microarrays to obtain the characteristics of the gene expression changes that are induced by R. solanacearum infection in resistant cultivar LS-89 and susceptible cultivar Ponderosa. Seedlings of LS-89 and Ponderosa at the five to six leaf-stage were inoculated on their stems just above the cotyledon by cutting to one-third the stem depth with a knife, adding a drop of bacterial suspension (1e+6 cfu/ml of R. solanacearum strain 8107S) or distilled water to the opening, and then clipping the wound site to avoid bending. Inoculated plants were grown in a growth chamber at 30ºC under 30,000 lux light intensity for 12 h a day. At 1dpi, stems were sampled by dissecting 5 mm long sections from 5 mm below the inoculation site. For each hybridization, RNA from 15 plants was used. Three biological replicates of microarray analysis were performed.