Project description:Coffee leaf miner is an important plague in coffee crops. Using subtracted cDNA libraries and nylon filter arrays, we analyzed the expression profile of 1536 expressed sequence tags (ESTs) of coffee plants from an hybrid progeny (C. arabica x C. racemosa), containg resistant (R) and susceptible plants (S) to the infestation of coffee leaf miner. Leaf discs were collected from non-infested plants (R control - RC; S control - SC), infested plants after moth oviposition (R oviposition - Ro; S oviposition - So) and infested after larvar eclosion (R eclosion - Re; S eclosion - Se). Isolation and characterization of Coffea genes induced during coffee leaf miner (Leucoptera coffeella) infestation. Plant Science 169(2):351-360 Keywords: ordered
Project description:Background: The soil environment is responsible for sustaining most terrestrial plant life on earth, yet we know surprisingly little about the important functions carried out by diverse microbial communities in soil. Soil microbes that inhabit the channels of decaying root systems, the detritusphere, are likely to be essential for plant growth and health, as these channels are the preferred locations of new root growth. Understanding the microbial metagenome of the detritusphere and how it responds to agricultural management such as crop rotations and soil tillage will be vital for improving global food production. Methods: The rhizosphere soils of wheat and chickpea growing under + and - decaying root were collected for metagenomics sequencing. A gene catalogue was established by de novo assembling metagenomic sequencing. Genes abundance was compared between bulk soil and rhizosphere soils under different treatments. Conclusions: The study describes the diversity and functional capacity of a high-quality soil microbial metagenome. The results demonstrate the contribution of the microbiome from decaying root in determining the metagenome of developing root systems, which is fundamental to plant growth, since roots preferentially inhabit previous root channels. Modifications in root microbial function through soil management, can ultimately govern plant health, productivity and food security.
Project description:Coffee leaf miner is an important plague in coffee crops. Using subtracted cDNA libraries and nylon filter arrays, we analyzed the expression profile of 1536 expressed sequence tags (ESTs) of coffee plants from an hybrid progeny (C. arabica x C. racemosa), containg resistant (R) and susceptible plants (S) to the infestation of coffee leaf miner. Leaf discs were collected from non-infested plants (R control - RC; S control - SC), infested plants after moth oviposition (R oviposition - Ro; S oviposition - So) and infested after larvar eclosion (R eclosion - Re; S eclosion - Se). Isolation and characterization of Coffea genes induced during coffee leaf miner (Leucoptera coffeella) infestation. Plant Science 169(2):351-360
Project description:With the aid of a biochip, carrying representative sequences from approximately 2200 sequences from the genome of isolate 9a5c from X. fastidiosa (Xf), microarray-based comparisons have been performed with 8 different Xf isolates obtained from coffee plants.
Project description:Understanding the mechanisms underlying the establishment of invasive plants is critical in community ecology. According to a widely accepted theory, plant-soil-microbe interactions mediate the effects of invasive plants on native species, thereby affecting invasion success. However, the roles and molecular mechanisms associated with such microbes remain elusive. Using high throughput sequencing and a functional gene microarray, we found that soil taxonomic and functional microbial communities in plots dominated by Ageratina adenophora developed to benefit the invasive plant. There were increases in nitrogen-fixing bacteria and labile carbon degraders, as well as soil-borne pathogens in bulk soil, which potentially suppressed native plant growth. Meanwhile, there was an increase of microbial antagonism in the A. adenophora rhizosphere, which could inhibit pathogenicity against plant invader. These results suggest that the invasive plant A. adenophora establishes a self-reinforcing soil environment by changing the soil microbial community. It could be defined as a ‘bodyguard/mercenary army’ strategy for invasive plants, which has important insights for the mitigation of plant invasion.
Project description:The fate of the carbon stocked in permafrost soils following global warming and permafrost thaw is of major concern in view of the potential for increased CH4 and CO2 emissions from these soils. Complex carbon compound degradation and greenhouse gas emissions are due to soil microbial communities, but their composition and functional potential in permafrost soils are largely unknown. Here, a 2 m deep permafrost and its overlying active layer soil were subjected to metagenome sequencing, quantitative PCR, and microarray analyses. The active layer soil and 2 m permafrost soil microbial community structures were very similar, with Actinobacteria being the dominant phylum. The two soils also possessed a highly similar spectrum of functional genes, especially when compared to other already published metagenomes. Key genes related to methane generation, methane oxidation and organic matter degradation were highly diverse for both soils in the metagenomic libraries and some (e.g. pmoA) showed relatively high abundance in qPCR assays. Genes related to nitrogen fixation and ammonia oxidation, which could have important roles following climatic change in these nitrogen-limited environments, showed low diversity but high abundance. The 2 m permafrost soil showed lower abundance and diversity for all the assessed genes and taxa. Experimental biases were also evaluated and showed that the whole community genome amplification technique used caused large representational biases in the metagenomic libraries. This study described for the first time the detailed functional potential of permafrost-affected soils and detected several genes and microorganisms that could have crucial importance following permafrost thaw. A 2m deep permafrost sample and it overlying active layer were sampled and their metagenome analysed. For microarray analyses, 8 other soil samples from the same region were used for comparison purposes.
Project description:Plants and rhizosphere microbes rely closely on each other, with plants supplying carbon to bacteria in root exudates, and bacteria mobilizing soil-bound phosphate for plant nutrition. When the phosphate supply becomes limiting for plant growth, the composition of root exudation changes, affecting rhizosphere microbial communities and microbially-mediated nutrient fluxes. To evaluate how plant phosphate deprivation affects rhizosphere bacteria, Lolium perenne seedlings were root-inoculated with Pseudomonas aeruginosa 7NR, and grown in axenic microcosms under different phosphate regimes (330 uM vs 3-6 uM phosphate). The effect of biological nutrient limitation was examined by DNA microarray studies of rhizobacterial gene expression.
Project description:The present study was conducted to evaluate the effects of the intake of three types of coffee (caffeinated, decaffeinated, and green unroasted coffee) on the livers of C57BL/6J mice fed a high-fat diet, and to extensively elucidate the physiological responses to coffee intake by analysing the findings obtained from a comprehensive transcriptomic analysis using DNA microarrays. The present study was conducted to evaluate the effects of the intake of three types of coffee (caffeinated, decaffeinated, and green unroasted coffee) on the livers of C57BL/6J mice fed a high-fat diet, and to extensively elucidate the physiological responses to coffee intake by analysing the findings obtained from a comprehensive transcriptomic analysis using DNA microarrays.