Project description:Drought is one of the most detrimental environmental factors that adversely affect crop production, thus jeopardizing food supplies for a growing world population. Over the past years, it has become evident that microorganisms associated with plants can enhance drought tolerance. However, the specific genetic and molecular mechanisms underpinning bacterial induction of drought tolerance in plants are still largely unknown. In our work, we have shown that a root endophytic Flavobacterium sp. 98 confers significant drought tolerance to Arabidopsis thaliana without compromising growth and yield. Here, we compared the transcriptome of Arabidopsis seedlings inoculated with Flavobacterium or mock (time series) to identify transcription reprograming induced by Flavo in plants.
Project description:Through 8 generations of selection, our group has developed a strain of rainbow trout that exhibits high growth rates on an economically and environmentally sustainable all plant protein, high-soy diet. The selected strain also shows superior performance in bacterial and viral disease challenges compared to commercial trout strains, and even a strain specifically selected over many generations for viral and bacterial disease resistance. The selection criteria was strictly focused on performance on plant-based diets, and therefore the physiological mechanisms responsible for the strain’s superior disease resistance remain unresolved. To better characterize the physiological mechanism behind the superior performance of the selected strain we compared the intestinal gene expression of the select strain to that of a commercial control line of trout during an experimental bacterial infection with Flavobacterium psychrophilum (Fp) (CSF 259-93), the causative agent of bacterial cold water disease (BCWD) in salmonids. At 65 days post hatch, all female rainbow trout from the select and commercial strain were stocked separately into four 150L tanks each, at a density of 45 fish per tank. For both strains of trout, three tanks of fish were experimentally infected with Fp by intramuscular injection and one control tank was mock challenged by sham injection. Sampling was conducted at 5 days post challenge (dpc) (Early Infection) and 21 dpc (Late/Recovered Infection). Two intestinal samples from each tank were pooled and two pools from each tank were utilized for RNAseq library preparation. The select strain of trout showed significantly better survival rates (Log-Rank Test, p < 0.0001) over the 21 day infection period, with 70 and 95 % mortality among the select and commercial strain, respectively. Reads from the RNAseq samples were quantified at the transcript level prior to evaluating differential transcript usage and differential gene expression between the strains of trout, infection time points, and disease status.
