scholarly journals TheArabidopsis GIBBERELLIN METHYL TRANSFERASE 1suppresses gibberellin activity, reduces whole-plant transpiration and promotes drought tolerance in transgenic tomato

2013 ◽  
Vol 37 (1) ◽  
pp. 113-123 ◽  
Author(s):  
IDO NIR ◽  
MENACHEM MOSHELION ◽  
DAVID WEISS
Keyword(s):  
Drought Tolerance ◽  
Transgenic Tomato ◽  
Methyl Transferase ◽  
Plant Transpiration ◽  
Whole Plant ◽  
Gibberellin Activity

scholarly journals Effect of Hardening to drought Tolerance on the Moisture Content of Sunflower Plant. III. Moisture Percentage in Whole Plant

2010 ◽  
Vol 7 (2) ◽  
pp. 888-894
Author(s):  
Baghdad Science Journal
Keyword(s):  
Drought Tolerance ◽  
Moisture Content ◽  
Agricultural Practices ◽  
Growth Stages ◽  
Full Irrigation ◽  
Whole Plant ◽  
Original Weight ◽  
Moisture Percentage ◽  
Plant Moisture ◽  
Plant Moisture Content

The study was conducted during spring seasons of 2000 and 2001.The aim was to study the changes in the moisture content of sunflower plants during growth stages under hardening conditions to drought tolerance .Agricultural practices were made according to recommendation. Asplit-split plots design was used with three replications. The main plots included irrigation treatments:irrigation to100%(full irrigation),75and50%of available water. The sub plots were the cultivars Euroflor and Flame.The sub-sub plots represented four seed soaking treatments: Control (unsoaked), soaking in water ,Paclobutrazol solution(250ppm),and Pix solution(500ppm). The soaking continued for 24 hours then seeds were dried at room temperature until they regained their original weight. Amount of water for each irrigation were calculated to satisfy water depletion in soil using a neutron meter. Results indicated that plant moisture content was not affected by irrigation treatments in both seasons and as a mean of seasons ,except after 72 days from planting in the season 2000.when stress 800 Kp caused a decreased in moisture content by 4.55and 5.18% compared with full irrigation and stress 600 Kp, respectively. Euroflor was superior over Flame after 30 days from planting by 13.64% in the season of 2000 and by 6.23% as a mean of seasons , and by 2.80% after 86 days from planting in the season of 2001.While Flame was superior by 2.75% after 58 days from planting in the season of 2001. Soaking in water , paclobutrazol and pix solutions increased plant moisture content by 4.56,3.92 and 3.82% after 86 days from planting in the season 2000 , soaking in water and paclobutrazol solution increased plant moisture content by 2.61 and 2.62% as amean of seasons compared with unsoaked treatment. In conclusion, soaking the seeds presowing in water or plant growth regulators could improve water relations of plants , and increase moisture content in plants tissues especially during flowering and seed filling , when the water requirements increased and associated with high temperature in spring season in Iraq.

scholarly journals Overexpression of Saussurea involucrata dehydrin gene SiDHN promotes cold and drought tolerance in transgenic tomato plants

PLoS ONE ◽  
2019 ◽  
Vol 14 (11) ◽  
pp. e0225090 ◽  
Author(s):  
Xinyong Guo ◽  
Li Zhang ◽  
Xiaozhen Wang ◽  
Minhuan Zhang ◽  
Yuxin Xi ◽  
...  
Keyword(s):  
Drought Tolerance ◽  
Transgenic Tomato ◽  
Saussurea Involucrata ◽  
Tomato Plants ◽  
Transgenic Tomato Plants ◽  
Dehydrin Gene

Genotypic variation in whole-plant transpiration efficiency in sorghum only partly aligns with variation in stomatal conductance

2019 ◽  
Vol 46 (12) ◽  
pp. 1072 ◽  
Author(s):  
Geetika Geetika ◽  
Erik J. van Oosterom ◽  
Barbara George-Jaeggli ◽  
Miranda Y. Mortlock ◽  
Kurt S. Deifel ◽  
...  
Keyword(s):  
Stomatal Conductance ◽  
Photosynthetic Capacity ◽  
Genotypic Variation ◽  
Vapour Pressure Deficit ◽  
Genotypic Differences ◽  
Transpiration Efficiency ◽  
Plant Transpiration ◽  
Leaf Chlorophyll ◽  
Residual Variation ◽  
Whole Plant

Water scarcity can limit sorghum (Sorghum bicolor (L.) Moench) production in dryland agriculture, but increased whole-plant transpiration efficiency (TEwp, biomass production per unit of water transpired) can enhance grain yield in such conditions. The objectives of this study were to quantify variation in TEwp for 27 sorghum genotypes and explore the linkages of this variation to responses of the underpinning leaf-level processes to environmental conditions. Individual plants were grown in large lysimeters in two well-watered experiments. Whole-plant transpiration per unit of green leaf area (TGLA) was monitored continuously and stomatal conductance and maximum photosynthetic capacity were measured during sunny conditions on recently expanded leaves. Leaf chlorophyll measurements of the upper five leaves of the main shoot were conducted during early grain filling. TEwp was determined at harvest. The results showed that diurnal patterns in TGLA were determined by vapour pressure deficit (VPD) and by the response of whole-plant conductance to radiation and VPD. Significant genotypic variation in the response of TGLA to VPD occurred and was related to genotypic differences in stomatal conductance. However, variation in TGLA explained only part of the variation in TEwp, with some of the residual variation explained by leaf chlorophyll readings, which were a reflection of photosynthetic capacity. Genotypes with different genetic background often differed in TEwp, TGLA and leaf chlorophyll, indicating potential differences in photosynthetic capacity among these groups. Observed differences in TEwp and its component traits can affect adaptation to drought stress.

scholarly journals Predicting Tree Sap Flux and Stomatal Conductance from Drone-Recorded Surface Temperatures in a Mixed Agroforestry System—A Machine Learning Approach

2020 ◽  
Vol 12 (24) ◽  
pp. 4070
Author(s):  
Florian Ellsäßer ◽  
Alexander Röll ◽  
Joyson Ahongshangbam ◽  
Pierre-André Waite ◽  
Hendrayanto ◽  
...  
Keyword(s):  
Machine Learning ◽  
Stomatal Conductance ◽  
Prediction Models ◽  
Hydrological Cycle ◽  
Machine Learning Algorithms ◽  
Sap Flux ◽  
Plant Transpiration ◽  
Surface Temperatures ◽  
Whole Plant ◽  
Wide Range

Plant transpiration is a key element in the hydrological cycle. Widely used methods for its assessment comprise sap flux techniques for whole-plant transpiration and porometry for leaf stomatal conductance. Recently emerging approaches based on surface temperatures and a wide range of machine learning techniques offer new possibilities to quantify transpiration. The focus of this study was to predict sap flux and leaf stomatal conductance based on drone-recorded and meteorological data and compare these predictions with in-situ measured transpiration. To build the prediction models, we applied classical statistical approaches and machine learning algorithms. The field work was conducted in an oil palm agroforest in lowland Sumatra. Random forest predictions yielded the highest congruence with measured sap flux (r2 = 0.87 for trees and r2 = 0.58 for palms) and confidence intervals for intercept and slope of a Passing-Bablok regression suggest interchangeability of the methods. Differences in model performance are indicated when predicting different tree species. Predictions for stomatal conductance were less congruent for all prediction methods, likely due to spatial and temporal offsets of the measurements. Overall, the applied drone and modelling scheme predicts whole-plant transpiration with high accuracy. We conclude that there is large potential in machine learning approaches for ecological applications such as predicting transpiration.

Effects of nitrogen supply on xylem cytokinin delivery, transpiration and leaf expansion of pea genotypes differing in xylem-cytokinin concentration

2004 ◽  
Vol 31 (9) ◽  
pp. 903 ◽  
Author(s):  
Ian C. Dodd ◽  
Chuong Ngo ◽  
Colin G. N. Turnbull ◽  
Christine A. Beveridge
Keyword(s):  
Sap Flow ◽  
Leaf Growth ◽  
Xylem Sap ◽  
Leaf Expansion ◽  
Growth Responses ◽  
Flow Rates ◽  
Plant Transpiration ◽  
Discernible Effect ◽  
Whole Plant ◽  
N Treatment

The rms2 and rms4 pea (Pisum sativum L.) branching mutants have higher and lower xylem-cytokinin concentration, respectively, relative to wild type (WT) plants. These genotypes were grown at two levels of nitrogen (N) supply for 18–20 d to determine whether or not xylem-cytokinin concentration (X-CK) or delivery altered the transpiration and leaf growth responses to N deprivation. Xylem sap was collected by pressurising de-topped root systems. As sap-flow rate increased, X-CK declined in WT and rms2, but did not change in rms4. When grown at 5.0 mm N, X-CKs of rms2 and rms4 were 36% higher and 6-fold lower, respectively, than WT at sap-flow rates equivalent to whole-plant transpiration. Photoperiod cytokinin (CK) delivery rates (the product of transpiration and X-CK) decreased more than 6-fold in rms4. Growth of plants at 0.5 mm N had negligible (< 10%) effects on transpiration rates expressed on a leaf area basis in WT and rms4, but decreased transpiration rates of rms2. The low-N treatment decreased leaf expansion by 20–25% and expanding leaflet N concentration by 15%. These changes were similar in all genotypes. At sap-flow rates equivalent to whole-plant transpiration, the low N treatment decreased X-CK in rms2 but had no discernible effect in WT and rms4. Since the low N treatment decreased transpiration of all genotypes, photoperiod CK delivery rates also decreased in all genotypes. The similar leaf growth response of all genotypes to N deprivation despite differences in both absolute and relative X-CKs and deliveries suggests that shoot N status is more important in regulating leaf expansion than xylem-supplied cytokinins. The decreased X-CK and transpiration rate of rms2 following N deprivation suggests that changes in xylem-supplied CKs may modify water use.

scholarly journals Expression of OsDREB2A in Transgenic Tomato Improves Drought Tolerance

2021 ◽  
Vol 26 (6) ◽  
pp. 3145-3154
Author(s):  
NADA HASSAN ◽  
NADIA M EL-SHAFEY ◽  
SALAH EL-DIN A KHODARY ◽  
HATTEM EL-SHABRAWI ◽  
ABDELFATTAH BADR
Keyword(s):  
Drought Tolerance ◽  
Abiotic Stress Tolerance ◽  
Soluble Sugars ◽  
Leaf Disc ◽  
Constitutive Expression ◽  
Transgenic Tomato ◽  
Agrobacterium Strain ◽  
Transgenic Lines ◽  
Responsive Element ◽  
Disc Assay

Dehydration responsive element binding (DREB) are important regulatory molecules which have a crucial role in abiotic stress tolerance. The productivity of tomato, as a drought-sensitive crop, is highly restricted by drought stress. The current study aimed at introducing the OsDERB2A gene into two tomato genotypes via Agrobacterium-mediated transformation system. Cotyledonary explants were pre-cultured for two days with Agrobacterium strain LBA4404 harboring pCAMBIA1301 with OsDREB2A driven by the constitutive promoter CaMV35S for transformation. Shoots were directly regenerated on MS medium containing 1 mg l-1 zeatin and 1 mg l-1 BAP, and in presence of 30 mg l-1 hygromycin as selective agent. Only eight weeks were needed to regenerate transgenic tomato using this protocol. An OD600 of 0.4 resulted in 64.3-76.9% transformation efficiency. Stable integration and expression of the OsDREB2A gene were confirmed in transgenic tomato using PCR and RT-PCR analyses, and drought tolerance of T0 transgenic lines was confirmed by leaf disc assay in 300 mM mannitol. The superior biomass, photosynthetic pigments, free soluble sugars and proline accumulation of OsDREB2A transgenic lines over wild type in response to mannitol-stress revealed their enhanced drought tolerance and indicated that the constitutive expression of OsDREB2A might modulate the expression of other drought responsive genes.

Sign in / Sign up

Export Citation Format

Share Document