ABSTRACT: Transcriptome profile for roots of the rice plants which showed favorable morpho-physiological adaptation when subjected to severe drought stress
Project description:In the field, abiotic stresses are rarely applied individually. Crops are often subjected to a combination of stresses. To date, no study has been performed on the proteomic investigation of the response of common wheat to a combination of drought and cold stresses. In this study, wheat seedlings exposed to drought-cold stress for 24 h showed inhibited growth, increased lipid peroxidation, relative electrolyte leakage, and soluble sugar contents. To determine the wheat protein response to drought-cold stress, iTRAQ-based quantitative proteomic and liquid chromatography tandem mass spectrometry (LC-MS/MS) methods were employed to determine the proteomic profiles of the roots and leaves of wheat seedlings exposed to drought-cold stress conditions. We identified 250 and 258 proteins with significantly altered abundance in the roots and leaves, respectively. These proteins were classified into several main groups, as follows: protein metabolism, stress/defense, carbohydrate metabolism, lipid metabolism, transcription-related processes, energy production, cell-wall and cytoskeleton metabolism, membrane and transportation, signal transduction, other metabolic processes, and unknown biological processes. Nine proteins were simultaneously presented in both roots and leaves exposed to drought-cold stress, and the majority of proteins identified differed from one another and displayed differently altered abundance. These findings uncovered organ-specific differences in adaptation to drought-cold stress. Exogenous abscisic acid (ABA) application conferred the plant with protection against drought-cold stress and significantly increased catalase and peroxidase enzyme activities, as well as the transcription of glutathione S-transferase and other 11 sample genes in the roots or leaves, respectively. These results suggested that ABA is a potentially vital factor that contributes to the drought-cold signaling pathway and a promising target for growth recovery. Furthermore, VIGS (virus-induced gene silencing)-treated plants generated for three candidate protein genes TaGRP2, CDCP and WCOR410c were subjected to drought-cold limitation, they showed more serious droop and wilt, increased rate of relative electrolyte leakage, and reduced relative water content (RWC) compared to viral control plants. These results may indicate that TaGRP2, CDCP and WCOR410c play important roles in conferring drought-cold tolerance in wheat. These findings can provide useful insights into the molecular mechanisms of drought-cold responses in higher plants.
Project description:To understand how OsNAM12.1 over-expression influences the target genes within qDTY12.1 and across the genome to affect root growth, the root transcriptome of Vandana, 481-B, IR64-Tr-E2, and IR64-WT were compared under control and drought conditions. Drought induced gene expression was studied in the roots of the rice plants subjected to severe drought. Seeds of Vandana, 481-B, IR64 and the OsNAM12.1 overexpression line (OsNAM Event 2) were sown in 5 biological replicates in a randomized complete block design for both the well watered and drought stress treatments.
Project description:We sequenced three small-RNA (sRNA) libraries constructed from leaves of sorghum subjected to three different treatments, well-watered (CK), mild drought (DR1) and severe drought (DR2). These findings will be useful for research on drought resistance and provide insights into the mechanisms of drought adaptation and resistance in sorghum.
Project description:A drought stress and recovery time course experiment was carried out under controlled environmental conditions. In order to find regulatory key mechanisms enabling plants to rapidly react to periodic stress events, beets were either subjected to 11 days of progressive drought, or were drought stressed for 9 days followed by gradual rewatering for 14 days. Based on physiological measurements of leaf water status and changes in morphology, plants experienced a switch from moderate to severe water stress between day 9 and 11 of drought.
Project description:Whole-genome duplication, or polyploidy, is common in many plant species and often leads to better adaptation to adverse environmental condition. However, little is known about the physiological and molecular determinants underlying adaptation. We examined the drought tolerance in diploid (2x) and autotetraploid (4x) clones of Rangpur lime (Citrus limonia) rootstocks grafted with 2x Valencia Delta sweet orange (Citrus sinensis) scions, named V/2xRL and V/4xRL, respectively. Physiological experiments to study root-shoot communication associated with gene expression studies in roots and leaves were performed. V/4xRL was much more tolerant to water deficit than V/2xRL. Gene expression analysis in leaves and roots showed that more genes related to the response to water stress were differentially expressed in V/2xRL than in V/4xRL. Prior to the stress, when comparing V/4xRL to V/2xRL, V/4xRL leaves had lower stomatal conductance and greater abscisic acid (ABA) content. In roots, ABA content was higher in V/4xRL and was associated to a greater expression of drought responsive genes, including CsNCED1, a pivotal regulatory gene of ABA biosynthesis. We conclude that tetraploidy modifies the expression of genes in citrus roots to regulate long-distance ABA signaling and adaptation to stress.
Project description:Whole-genome duplication, or polyploidy, is common in many plant species and often leads to better adaptation to adverse environmental condition. However, little is known about the physiological and molecular determinants underlying adaptation. We examined the drought tolerance in diploid (2x) and autotetraploid (4x) clones of Rangpur lime (Citrus limonia) rootstocks grafted with 2x Valencia Delta sweet orange (Citrus sinensis) scions, named V/2xRL and V/4xRL, respectively. Physiological experiments to study root-shoot communication associated with gene expression studies in roots and leaves were performed. V/4xRL was much more tolerant to water deficit than V/2xRL. Gene expression analysis in leaves and roots showed that more genes related to the response to water stress were differentially expressed in V/2xRL than in V/4xRL. Prior to the stress, when comparing V/4xRL to V/2xRL, V/4xRL leaves had lower stomatal conductance and greater abscisic acid (ABA) content. In roots, ABA content was higher in V/4xRL and was associated to a greater expression of drought responsive genes, including CsNCED1, a pivotal regulatory gene of ABA biosynthesis. We conclude that tetraploidy modifies the expression of genes in citrus roots to regulate long-distance ABA signaling and adaptation to stress.
Project description:With frequent fluctuations in global climate, plants often experience co-occurring dry-wet cycles and pathogen infection and this combination adversely affects plant survival. In the past, some studies indicated that morpho-physiological responses of plants to the combined stress are different from the individual stressed plants. However, interaction of drought stressed or drought recovered plants with pathogen has not been widely studied at molecular level. Such studies are important to understand the defense pathways that operate as part of combined stress tolerance mechanism. In this study, Arabidopsis plants were exposed to individual drought stress (soil drying at 40% FC, D), Pseudomonas syringae pv tomato DC3000 (PStDC3000), infection and their combination. Plants recovered from drought stress were also exposed to PStDC3000. Beside we have also infiltrated P. syringae pv tabaci (PSta, non-host pathogen) individually or in combination with drought stress. Using Affymetrix WT gene 1.0 ST array, global transcriptome profiling of plants leaves under individual drought stress and pathogen infection was compared with their combination. Results implicate that plants exposed to combined drought and pathogen stress experience a new state of stress where each combination of stressor and their timing defines the plant responses and thus should be studied explicitly. Global transcriptional analysis in Arabidopsis leaves exposed to individual and combined drought and pathogen stress.
Project description:To understand how the qDTY12.1 interacts with other genes within the genome to give better physiological adaptations and better yield; the leaves transcriptome of DTY12.1 parents (Vandana , Way Rarem) and DTY12.1 NIL (481-B) were compared under control and drought conditions. Drought induced gene expression was studied in the leaves of the rice plants subjected to severe reproductive stage drought. Seeds of Vandana, Way Rarem, and 481-B were sown into rotovated soil at a rate of 2.0 g m-1 into plots of 3 rows X 3 m. The three genotypes were sown in three replications in a randomized complete block design.
Project description:Plants have evolved to possess adaptation mechanism to cope with drought stress by reprograming transcriptional networks through drought responsive transcription factors, which in turn mediate morphological and physiological changes. NAM, ATAF1-2, and CUC2 (NAC) transcription factors are known to be associated with various developmental processes and stress tolerance. In this study, we functionally characterized the rice drought responsive NAC transcription factor OsNAC14. OsNAC14 was predominantly induced at meiosis stage, and induced by drought, high salinity, ABA and low temperature in leaves than roots. Overexpression of OsNAC14 resulted in drought tolerance at the vegetative growth stage and enhanced filling rate at vegetative growth. OsNAC14 overexpression elevated expression of genes related to DNA damage repair, defense response, strigolactone biosynthesis, which correlated with resistance to drought tolerance. Furthermore, OsNAC14 directly bound to the promoter of drought inducible OsRAD51A1, a key component in homologous recombination in DNA repair system. These results indicate that OsNAC14 mediate drought tolerance by recruiting factors involved in DNA damage repair and defense response to enable plant to protect from cellular damage caused by drought stress, thereby provide mechanism for drought tolerance.
Project description:The aim of this study was to evaluate the physiological response and the expression analysis of `Dusa´ avocado rootstocks subjected to two different levels of water stress, and their subsequent recovery. At the beginning of the experiment, avocado plants were divided in Control plants (watered to field capacity (Fc) throughout the experiment) and stressed plants that were subjected to controlled substrate drying-up until they reached 50% of Fc (mild-WS) and 25% of Fc (severe-WS), respectively. Afterwards, plants were fully irrigated to assess drought recovery response. A set of physiological measurement were taken at leaf and whole-plant levels to assess avocado response to each level of water stress and rewatering. Root samples were collected in mild-WS and severe-WS and gene expression analysis was carried out using a targeted cDNA avocado stress microarray containing transcripts from de novo sequencing of 'Dusa' in response to biotic and abiotic stress. Avocado gene expression profiles under different levels of water stress are discussed in order to shed light on the molecular mechanisms associated with water deprivation in Dusa avocado rootstocks.