In order to explore the relevant molecular genetic mechanisms of photosynthetic rate (PR) and chlorophyll content (CC) in rice (Oryza sativa L.), we conducted a series of related experiments using a population o...In order to explore the relevant molecular genetic mechanisms of photosynthetic rate (PR) and chlorophyll content (CC) in rice (Oryza sativa L.), we conducted a series of related experiments using a population of recombinant inbred lines (Zhenshan97B x IRAT109). We found a significant correlation between CC and PR (R = 0.19**) in well-watered conditions, but no significant correlation during water stress (r = 0.08). We detected 13 main quantitative trait loci (QTLs) located on chromosomes 1, 2, 3, 4, 5, 6, and 10, which were associated with CC, including six QTLs located on chromosomes 1, 2, 3, 4, and 5 during water stress, and seven QTLs located on chromosomes 2, 3, 4, 6, and 10 in well-watered conditions. These QTLs explained 47.39% of phenotypic variation during water stress and 56.19% in well-watered conditions. We detected four main QTLs associated with PR; three of them (qPR2, qPR10, qPR11) were located on chromosomes 2, 10, and 11 during water stress, and one (qPR10) was located on chromosome 10 in well-watered conditions. These QTLs explained 34.37% and 18.41% of the phenotypic variation in water stress and well-watered conditions, respectively. In total, CC was largely controlled by main QTLs, and PR was mainly controlled by epistatic QTL pairs.展开更多
In a 2-year experiment, 187 genotypes were grown under well-watered and drought stress conditions, imposed at panicle initiation stage. The relationship of genotypic variation in yield under drought conditions to pote...In a 2-year experiment, 187 genotypes were grown under well-watered and drought stress conditions, imposed at panicle initiation stage. The relationship of genotypic variation in yield under drought conditions to potential yield, heading date and flowering delay, reduction in plant height, and to a drought response index (DRI) was detected. Grain yield under drought stress conditions was associated with yield under well-watered conditions (r= 0.47^**, and r= 0.61^** during 2 years of tests). The delay of heading date ranged from -1 (no delay) to 24days, and was negatively associated with grain yield (r =-0.40^*), spikelet fertility percentage (r =-0.40^**), harvest index (r =-0.58^**), but positively associated with yield reduction percentage (r = 0.60^**). The reduction in plant height was negatively associated with grain yield (r =-0.24^**, and r=-0.29^**), spikelet fertility percentage (r = -0.23^**, and r= -0.21^*), harvest index (r = -0.37^**, and r= -0.54^**), and positively associated with yield reduction percentage (r = 0.58^**, and r= 0.58^**) in 2003 and 2004, respectively. The DRI of genotypes was strongly associated with grain yield (r = 0.87^**, and r= 0.77^**), fertility percentage (r = 0.66^** and r= 0.54^**), harvest index (r= 0.67^** and r= 0.61^**), and negatively associated with grain reduction percentage (r=-0.70^**, and r=-0.73^**) under drought stress. The results indicate that genotypes with drought resistance can be identified by measuring yield potential, delay in flowering, reduction in plant height, or DRI under test environments of well-watered and drought stress.展开更多
Two upland rice varieties (IRAT109, IAPAR9) and one lowland rice variety (Zhenshan 97B) were planted in summer and treated with both normal (full water) and drought stress in the reproductive stage. Panicle wate...Two upland rice varieties (IRAT109, IAPAR9) and one lowland rice variety (Zhenshan 97B) were planted in summer and treated with both normal (full water) and drought stress in the reproductive stage. Panicle water potential (PWP) and leaf water potential (LWP) were measured every 1.0-1.5 h over 24 h on sunny days. Both PWP and LWP of upland varieties started to decrease later, maintained a higher level and recovered more quickly than that of the lowland variety. The results show that PWP can be used as an indicator of plant water status based on the parallel daily changes, and the high correlation between PWP and LWP. Similar correlations were also observed between PWP, LWP and eight traits related to plant growth and grain yield formation. PWP seemed to be more effective for distinguishing the upland rice varieties with different drought-tolerant ability. Differences in PWP and LWP between upland and lowland rice varieties were also observed at noon even under normal water conditions, implying the incorporation of the drought-tolerant mechanism to improve the photosynthesis and yield of traditional paddy rice.展开更多
Following the idea of partial root-zone drying (PRD) in crop cultivation,the morphological and physiological responses to partial root osmotic stress (PROS) and whole root osmotic stress (WROS) were investigated...Following the idea of partial root-zone drying (PRD) in crop cultivation,the morphological and physiological responses to partial root osmotic stress (PROS) and whole root osmotic stress (WROS) were investigated in rice.WROS caused stress symptoms like leaf rolling and membrane leakage.PROS stimulated stress signals,but did not cause severe leaf damage.By proteomic analysis,a total of 58 proteins showed differential expression after one or both treatments,and functional classification of these proteins suggests that stress signals regulate photosynthesis,carbohydrate and energy metabolism.Two other proteins (anthranilate synthase and submergence-induced nickel-binding protein) were upregulated only in the PROS plants,indicating their important roles in stress resistance.Additionally,more enzymes were involved in stress defense,redox homeostasis,lignin and ethylene synthesis in WROS leaves,suggesting a more comprehensive regulatory mechanism induced by osmotic stress.This study provides new insights into the complex molecular networks within plant leaves involved in the adaptation to osmotic stress and stress signals.展开更多
基金supported by grants from the National Program on the Development of Basic Research (Grant No. 2011CB100200)the National Program of High Technology Development (Grant No. 2010AA101801)+1 种基金the National Program of Plant Transgenic Breeding (Grant No. 2008ZX08009-003)the National Natural Science Foundation of China (Grant No. 30671114)
基金Supported by the National Natural Science Foundation of China (30040025)Chinese Ministry of Science and Technology (2003AA207010 and 2004B17200)+1 种基金the Rockefeller Foundation, the Key Program of Nature Science Foundation of Hunan Province (090XHN)the Personnel Foundation of Jishou University
文摘In order to explore the relevant molecular genetic mechanisms of photosynthetic rate (PR) and chlorophyll content (CC) in rice (Oryza sativa L.), we conducted a series of related experiments using a population of recombinant inbred lines (Zhenshan97B x IRAT109). We found a significant correlation between CC and PR (R = 0.19**) in well-watered conditions, but no significant correlation during water stress (r = 0.08). We detected 13 main quantitative trait loci (QTLs) located on chromosomes 1, 2, 3, 4, 5, 6, and 10, which were associated with CC, including six QTLs located on chromosomes 1, 2, 3, 4, and 5 during water stress, and seven QTLs located on chromosomes 2, 3, 4, 6, and 10 in well-watered conditions. These QTLs explained 47.39% of phenotypic variation during water stress and 56.19% in well-watered conditions. We detected four main QTLs associated with PR; three of them (qPR2, qPR10, qPR11) were located on chromosomes 2, 10, and 11 during water stress, and one (qPR10) was located on chromosome 10 in well-watered conditions. These QTLs explained 34.37% and 18.41% of the phenotypic variation in water stress and well-watered conditions, respectively. In total, CC was largely controlled by main QTLs, and PR was mainly controlled by epistatic QTL pairs.
基金Jointly supported by grants from Chinese Ministry of Agriculture(948-2001-101)Shanghai Municipal Science and Technology Commission(2005DJ14008)Shanghai Municipal Agriculture Commission and the Rockefeller Foundation(2004FS071),New York,USA.
文摘In a 2-year experiment, 187 genotypes were grown under well-watered and drought stress conditions, imposed at panicle initiation stage. The relationship of genotypic variation in yield under drought conditions to potential yield, heading date and flowering delay, reduction in plant height, and to a drought response index (DRI) was detected. Grain yield under drought stress conditions was associated with yield under well-watered conditions (r= 0.47^**, and r= 0.61^** during 2 years of tests). The delay of heading date ranged from -1 (no delay) to 24days, and was negatively associated with grain yield (r =-0.40^*), spikelet fertility percentage (r =-0.40^**), harvest index (r =-0.58^**), but positively associated with yield reduction percentage (r = 0.60^**). The reduction in plant height was negatively associated with grain yield (r =-0.24^**, and r=-0.29^**), spikelet fertility percentage (r = -0.23^**, and r= -0.21^*), harvest index (r = -0.37^**, and r= -0.54^**), and positively associated with yield reduction percentage (r = 0.58^**, and r= 0.58^**) in 2003 and 2004, respectively. The DRI of genotypes was strongly associated with grain yield (r = 0.87^**, and r= 0.77^**), fertility percentage (r = 0.66^** and r= 0.54^**), harvest index (r= 0.67^** and r= 0.61^**), and negatively associated with grain reduction percentage (r=-0.70^**, and r=-0.73^**) under drought stress. The results indicate that genotypes with drought resistance can be identified by measuring yield potential, delay in flowering, reduction in plant height, or DRI under test environments of well-watered and drought stress.
文摘Two upland rice varieties (IRAT109, IAPAR9) and one lowland rice variety (Zhenshan 97B) were planted in summer and treated with both normal (full water) and drought stress in the reproductive stage. Panicle water potential (PWP) and leaf water potential (LWP) were measured every 1.0-1.5 h over 24 h on sunny days. Both PWP and LWP of upland varieties started to decrease later, maintained a higher level and recovered more quickly than that of the lowland variety. The results show that PWP can be used as an indicator of plant water status based on the parallel daily changes, and the high correlation between PWP and LWP. Similar correlations were also observed between PWP, LWP and eight traits related to plant growth and grain yield formation. PWP seemed to be more effective for distinguishing the upland rice varieties with different drought-tolerant ability. Differences in PWP and LWP between upland and lowland rice varieties were also observed at noon even under normal water conditions, implying the incorporation of the drought-tolerant mechanism to improve the photosynthesis and yield of traditional paddy rice.
基金supported by grants from the National Basic Research Program of China (973 Program,no. 2010CB125901)the National High Technology Research and Development Program of China (863 Program,no. 2007AA100063)+2 种基金the National Natural Science Foundation of China (Key Project,no. 30830071)the National Special Program on Research and Commercialization of Transgenic Plant (no. 2009ZX8009-007B)the Shanghai Municipal Science and Technology Mission (Key Basic Research Project,no. 2009DJ1400501)
文摘Following the idea of partial root-zone drying (PRD) in crop cultivation,the morphological and physiological responses to partial root osmotic stress (PROS) and whole root osmotic stress (WROS) were investigated in rice.WROS caused stress symptoms like leaf rolling and membrane leakage.PROS stimulated stress signals,but did not cause severe leaf damage.By proteomic analysis,a total of 58 proteins showed differential expression after one or both treatments,and functional classification of these proteins suggests that stress signals regulate photosynthesis,carbohydrate and energy metabolism.Two other proteins (anthranilate synthase and submergence-induced nickel-binding protein) were upregulated only in the PROS plants,indicating their important roles in stress resistance.Additionally,more enzymes were involved in stress defense,redox homeostasis,lignin and ethylene synthesis in WROS leaves,suggesting a more comprehensive regulatory mechanism induced by osmotic stress.This study provides new insights into the complex molecular networks within plant leaves involved in the adaptation to osmotic stress and stress signals.