Project description:Roots make the first contact with the soil environment and are the first responders of stress. These root behaviors are quantifiable and adaptive. The response of rice varieties in mechanical and salinity stress was measured in a novel experimental setup that mimics the soil environment. We analyzed the response of roots by means of SAC (Stress Adaptation Coefficient) in 28 rice varieties that include high-yield salt tolerant varieties as well as geographically isolated native rice varieties. cDNA microarray of IR64 root-tip shows about 6000 common transcripts to be differentially regulated among the two stresses and common pathways were identified. Overall, our study indicates that there is an important commonality in the molecular basis of salt and mechanical stress and presents an easy-to-perform early establishment stress screen for rice varieties.
Project description:Climate change is affecting crop production due to soil salinization and water scarcity, and is predicted to worsen in the coming years. Rice is a major staple food and the most salt-sensitive cereal. High salinity in the soil triggers several adaptive responses in rice to cope with osmotic and ionic stress at the physiological, cellular and molecular levels. A major QTL for salinity tolerance, named Saltol, is present on chromosome 1 of Indian rice landrace varieties such as Pokkali and Nona Bokra. In this study, we characterized the physiological and early proteomic responses to salinity in FL478, an inbred rice line harboring the Saltol region. For this, plantlets were cultured in hydroponic cultures with 100 mM NaCl and evaluated at 6, 24 and 48h. At the physiological level, salinity significantly reduced shoot length after 48 h, whereas root length significantly increased. Moreover, the Na+/K+ ratio was maintained at lower levels in the shoots compared to the roots FL478 plantlets. On the other hand, roots showed a faster and more coordinated proteomic response than shoots, which was evident from only 6h of treatment. These responses were markedly related with transcription- and translation-related proteins. Moreover, roots exhibited a higher accumulation of stress-related proteins in response to salinity treatment, like peroxidase and SalT, which are both present in the Saltol QTL. Both, physiological and proteomic response, showed that roots respond in a highly adaptive manner to salinity stress compared to shoots, which suggests that this tissue is critical to the tolerance observed in varieties harbouring the Saltol region.
Project description:To understand the responses of plants to environmental stresses will help mitigate the problems via creating stress-tolerant crop cultivars. We have carried out comparative expression analysis of roots of two soybean varieties Williams 82 and DT2008 that have constrasting drought-responsive phenotype under dehydration and well-watered (control) conditions. Affymetrix’s whole Soybean Gene Expression Microarray (66K) was used. The Williams 82 and DT2008 soybean plants were grown for 14 days in the vermiculite soil under greenhouse conditions. The whole plants of 14-d-old plants were detached and exposed to dehydration on KimTowel papers for 0 (well-watered, control), 2 and 10 h. All roots of independent 14-d-old plants were collected. Total RNA was prepared and used for the microarray hybridization. Three independent biological replicates were used for each plant sample.
Project description:The secretion of metabolites by plant roots is a key determinant of microbial growth and colonisation. We have used Pisum sativum and its natural symbiont Rhizobium leguminosarum (it can form N2 fixing nodules on pea roots) to study the natural metabolites secreted by roots. To do this root secretion was harvested from pea plants grown under sterile conditions. This root exudate was then concentrated and used as a sole carbon and nitrogen source for growth of the bacteria in the laboratory. These bacteria were harvested in mid-exponential growth and RNA extracted for microarray analysis. As control cultures the bacteria were grown on 30 mM pyruvate as a carbon source and 10 mM ammonium chloride as a nitrogen source and RNA extracted. Two colour microarrays were performed using root exudate cultures versus pyruvate ammonia grown cultures. This was done in biological triplicate.
Project description:Two varieties of turmeric, FMO (Fat Mild Orange) and TYA (Thin Yellow Aromatic) were compared. Rhizomes were harvested 3, 5, and 7 months after planting, roots were harvested at 7 months, and leaves were harvested at 7 months. Plants were grown under controlled conditions in the greenhouse.
Project description:In this study we perform a transcriptomics analysis of two maize (Zea mays) organs, roots and leaves, from plants grown in the presence of a sufficient (1000 uM) or limiting (10 uM) concentration of soil phosphate.
Project description:Background: Heavy metal cadmium (Cd) is a common environmental pollutant in soils, which has an negative impacts on crop growth and development. At present, cadmium has become a major soil and water heavy metal pollutant, which not only causes permanent and irreversible health problems for humans, but also causes a significant reduction in crop yields. Results: This study examined the chemical forms of Cd in the roots of two wheat varieties (M1019 and Xinong20) by continuous extraction and analyzed differences in distribution characteristics of Cd in the root cell wall, cytoplasm, and organelles by elemental content determination and subcellular separation. Furthermore, we conducted proteomics analysis of the roots of the two varieties under Cd pollution using mass spectrometry quantitative proteomics techniques. A total of 11,651 proteins were identified, of which 10,532 proteins contained quantitative information. In addition, the differentially expressed proteins in the two varieties were related to DNA replication and repair, protein metabolism, and the glutathione metabolism pathway. Conclusion: The results of this study improve our understanding of the mechanism of plant responses to Cd stress.