Response of rice leaf expansion to water deficit temperature, and vapor pressure in different rice genotypes
2007
Mabesa, R. | Cairns, J. | Serraj, R., International Rice Research Inst., DAPO Box 7777, Metro Manila (Philippines)
Reduction in leaf expansion is one of the first responses to water deficit, occurring before changes in other physiological processes such as photosynthesis, transpiration, and metabolism. To dissect the underlying physiological and genetic mechanisms controlling leaf expansion under water-limited conditions, the authors are using a combined approach involving leaf elongation modeling, quantitative genetics, and transcript profiling. To strengthen this application, the authors will also be using modelling to predict how different allelic combinations will affect growth under different drought scenarios. Here, they present work on the response of leaf elongation to different environmental parameters such as drought stress, temperature, and vapor pressure deficit (VPD). Rates of leaf elongation were measured on plants (drought-tolerant, APO and drought-sensitive, IR72) grown in growth cabinets under controlled environmental conditions. Maximum leaf elongation rate per unit thermal time was determined under different levels of VPD and temperature regimes at different levels of soil moisture. Data were used to established response curves of leaf elongation rate to VPD and temperature. Leaf elongation rate was also determined under field vegetative drought stress in two rice mapping populations (Apo/IR72 and Vandana/Moroberekan). Regions of the genome associated with leaf development and growth under well-watered conditions and drought stress have been identified. These results are important for understanding genotype x environment interaction on tissue growth regulation under water-limited conditions and will be applied to ongoing work on the analysis of the genetic basis of tissue growth under water deficit.
显示更多 [+] 显示较少 [-]