• The Plant Pathology Journal
• /
• v.29 no.4
• /
• pp.427-434
• /
• 2013

2R,3R-Butanediol, a volatile compound produced by certain rhizobacteria, is involved in induced drought tolerance in Arabidopsis thaliana through mechanisms involving stomatal closure. In this study, we examined the involvement of nitric oxide and hydrogen peroxide in induced drought tolerance, because these are signaling agents in drought stress responses mediated by abscisic acid (ABA). Fluorescence-based assays showed that systemic nitric oxide and hydrogen peroxide production was induced by 2R,3R-butanediol and correlated with expression of genes encoding nitrate reductase and nitric oxide synthase. Co-treatment of 2R,3R-butanediol with an inhibitor of nitrate reductase or an inhibitor of nitric oxide synthase lowered nitric oxide production and lessened induced drought tolerance. Increases in hydrogen peroxide were negated by co-treatment of 2R,3R-butanediol with inhibitors of NADPH oxidase, or peroxidase. These findings support the volatile 2R,3R-butanediol synthesized by certain rhizobacteria is an active player in induction of drought tolerance through mechanisms involving nitric oxide and hydrogen peroxide production.

• Korean Journal of Environmental Agriculture
• /
• v.29 no.2
• /
• pp.159-164
• /
• 2010

Imidacloprid is a systemic insecticide which has been used widely in various crops to control insects. In the present study, we demonstrated that pre-treatment of imidacloprid significantly induced tolerance to drought in plant. Relative water content, chlorophyll levels, and recovery rate upon rehydration after drought stress in tobacco plants pre-treated with imidacloprid were higher levels than the control plants. Induced drought tolerance by imidacloprid treatments in red pepper was also demonstrated by measurement of recovery rate and fresh weight upon drought stress. Taken together, our results suggest that imidacloprid, in addition to exerting direct insecticidal activity, may also protect plants by induced tolerance to drought in plant.

• The Plant Pathology Journal
• /
• v.28 no.1
• /
• pp.101-106
• /
• 2012

Trifloxystrobin is a strobilurin fungicide, which possesses broad spectrum control against fungal plant diseases. We demonstrated that pre-treating red pepper plants with trifloxystrobin resulted in increased plant growth and leaf chlorophyll content compared with those in control plants. Relative water content of the leaves and the survival rate of intact plants indicated that plants acquired systemic tolerance to drought stress following trifloxystrobin pre-treatment. The recovery rate by rehydration in the drought treated plant was better in those pre-treated with trifloxystrobin than that in water treated plants. Induced drought tolerance activity by trifloxystrobin was sustained for 25 days after initial application. The trifloxystrobin treated red pepper plants also had induced systemic tolerance to other abiotic stresses, such as frost, cold, and high temperature stresses. These findings suggest that applying the chemical fungicide trifloxystrobin induced systemic tolerance to certain abiotic stresses in red pepper plants.

• The Plant Pathology Journal
• /
• v.28 no.2
• /
• pp.202-206
• /
• 2012

Root colonization by the rhizobacterium Pseudomonas chlororaphis O6 in Arabidopsis thaliana Col-0 plants resulted in induced tolerance to drought and salinity caused by halide salt-generated ionic stress but not by osmotic stress caused by sorbitol. Stomatal apertures decreased following root colonization by P. chlororaphis O6 in both wild-type and ABA-insensitive Arabidopsis mutant plants. These results suggest that an ABA-independent stomatal closure mechanism in the guard cells of P. chlororaphis O6-colonized plants could be a key phenotype for induced systemic tolerance to drought and salt stress.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.42 no.3
• /
• pp.208-214
• /
• 2022

Drought stress is a condition that occurs frequently in the field, it reduces of the agricultural yield of field crops. The aim of the study was to screen drought-adapted genotype of Italian rye grass. The experiments were conducted between the two Italian ryegrass (Lolium multiflorum L.) cultivars viz. Hwasan (H) and Kowinearly (KE). The plants were exposed to drought for 14 days. The results suggest that the morphological traits and biomass yield of KE significantly affected by drought stress-induced oxidative stress as the hydrogen peroxide (H₂O₂) level was induced, while these parameters were unchanged or less affected in H. Furthermore, the cultivar H showed better adaptation by maintaining several physiological parameter including photosystem-II (Fv/Fm), water use efficiency (WUE) and relative water content (RWC%) level in response to drought stress. These results indicate that the cultivar H shows improved drought tolerance by generic variation, improving photosynthetic efficiency and reducing oxidative stress damages under drought stress. These findings can be useful to the breeder and farmer for improving drought tolerance in Italian rye grass through breeding programs.

• The Plant Pathology Journal
• /
• v.29 no.2
• /
• pp.209-220
• /
• 2013

Root colonization by Pseudomonas chlororaphis O6 induces systemic drought tolerance in Arabidopsis thaliana. Microarray analysis was performed using the 22,800-gene Affymetrix GeneChips to identify differentially-expressed genes from plants colonized with or without P. chlororaphis O6 under drought stressed conditions or normal growth conditions. Root colonization in plants grown under regular irrigation condition increased transcript accumulation from genes associated with defense, response to reactive oxygen species, and auxin- and jasmonic acid-responsive genes, but decreased transcription factors associated with ethylene and abscisic acid signaling. The cluster of genes involved in plant disease resistance were up-regulated, but the set of drought signaling response genes were down-regulated in the P. chlororaphis O6-colonized under drought stress plants compared to those of the drought stressed plants without bacterial treatment. Transcripts of the jasmonic acid-marker genes, VSP1 and pdf-1.2, the salicylic acid regulated gene, PR-1, and the ethylene-response gene, HEL, also were up-regulated in plants colonized by P. chlororaphis O6, but differed in their responsiveness to drought stress. These data show how gene expression in plants lacking adequate water can be remarkably influenced by microbial colonization leading to plant protection, and the activation of the plant defense signal pathway induced by root colonization of P. chlororaphis O6 might be a key element for induced systemic tolerance by microbes.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.160-160
• /
• 2017

Drought stress is a major constraint of crop development and productivity. Plants have evolutionally developed several mechanisms at the molecular, cellular, and physiological levels to overcome drought stress. The basic Leucine zipper (bZIP) transcription factor (TF) family members are starting to be concerned about their roles in drought stress responses. In this study, we functionally characterized OsbZIP66, a rice group-E bZIP TF, to be associated with rice drought tolerance mechanisms. Expression of OsbZIP66 was significantly induced upon treatments of rice plants with drought, high salinity, and ABA. These observations and the fact that the OsbZIP66 promoter contains ten ABA-responsive elements suggest that OsbZIP66 is up-regulated by drought stress in an ABA-dependent manner. Overexpression of both OsbZIP66 in a whole plant body and specifically in roots enhanced drought tolerance of rice plants, indicating that the rice drought tolerance positively correlates with the expression levels of OsbZIP66. Thus, our results demonstrated that OsbZIP66 has a potential for use in biotechnological development of high-yielding rice plants under drought conditions.

• Journal of Applied Biological Chemistry
• /
• v.51 no.2
• /
• pp.50-56
• /
• 2008

As one way to approach to cold defense mechanism in plants, we previously identified the gene for protein-tyrosine phosphatase (CaTPP1) from hot pepper (Capsicum annuum) using cDNA microarray analysis coupled with Northern blot analysis. We showed that the CaTPP1 gene was strongly induced by cold, drought, salt and ABA stresses. The CaTPP1 gene was engineered under control of CaMV 35S promoter for constitutive expression in transgenic tobacco plants by Agrobacterium-mediated transformation. The resulting CaTPP1 transgenic tobacco plants showed significantly increased cold stress resistance. It also appeared that some of the transgenic tobacco plants showed increased drought tolerance. The CaTPP1 transgenic plants showed no visible phenotypic alteration compared to wild type plants. These results showed the involvement of protein tyrosine phosphatase in tolerance of abiotic stresses including cold and drought stress.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.115-115
• /
• 2017

Zinc finger proteins constitute a large family which has been studied to have various functions in different organisms. Tandem CCCH zinc finger proteins (TZFs), members of the zinc finger protein family, are known to participate as post-transcriptional regulators of gene expression in eukaryotes. Here, we showed that the OsZn15, a gene for tandem CCCH zinc finger protein, is induced by abiotic stress and its overexpression in transgenic rice plants (PGD1:OsZn15) gains higher drought tolerance. Gene expression analysis of promoter:GFP plants revealed that OsZn15 is specifically expressed in anther and embryo, but not in vegetative organs. In-field evaluation, grain yield was higher in the PGD1:OsZn15 than nontransgenic plants under drought conditions. Interestingly, OsZn15 is shown to not only localize at nucleus but also co-localize with both processing bodies (PB) and stress granules (SG), two messenger ribo-nucleoprotein complexes which are known to activate by forming cytoplasmic foci under stress conditions. In sum, these results suggest that OsZn15 increases drought stress tolerance of rice probably by participating in RNA turnover in PB and SG.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.168-168
• /
• 2017

Drought conditions during cultivation reduce agricultural production yield less than a theoretical maximum yield under normal condition. Plant specific NAC transcription factors in rice are known to play an essential roles in stress resistance transcriptional regulation. In this study, we report the rice (Oryza sativa L japonica) NAM, AFTF and CUC transcription factor OsNAC17, which is predominantly induced by abiotic stress in leaf, was contribute to the drought tolerance mediated reactive oxygen species (ROS) in transgenic rice plants. Constitutive (PGD1) promoter was introduced to overexpress OsNAC17 and produced the transgenic PDG1:OsNAC17. Overexpression of OsNAC17 throughout the whole plant improved drought resistance phenotype at the vegetative stage. Morphological characteristics such as grain yield, grain filling rate, and total grain weight improved by 22~64% over wild type plants under drought conditions during the reproductive stage. The improved drought tolerance in transgenic rice was involved in reducing stomatal density up to 15% than in wild type plants and in increasing reactive oxygen species-scavenging enzyme. DEG profiling experiment identified 119 up-regulated genes by more than twofold (P<0.01). These genes included UDP-glycosyltransferase family protein, similar to 2-alkenal reductase (NADPH-dependent oxireductase), similar to retinol dehydrogenase 12, Lipoxygenase, and NB-ARC domain containing protein related in cell death. Furthermore, OsNAC17 was act as a transcriptional activator, which has an activation domain in C-terminal region. These result demonstrate that the overexpression of OsNAC17 improve drought tolerance by regulating ROS scavenging enzymes and by reducing stomatal density