Flag leaf angle is one of the key target traits in high yield wheat breeding.A smaller flag leaf angle reduces shading and enables plants to grow at a higher density,which increases yield.Here we identified a mutant,j...Flag leaf angle is one of the key target traits in high yield wheat breeding.A smaller flag leaf angle reduces shading and enables plants to grow at a higher density,which increases yield.Here we identified a mutant,je0407,with an 84.34%-89.35%smaller flag leaf angle compared with the wild type.The mutant also had an abnormal lamina joint and no ligule or auricle.Genetic analysis indicated that the ligule was controlled by two recessive genes,which were mapped to chromosomes 2AS and 2DL.The mutant allele on chromosome 2AS was named Tafla1b,and it was fine mapped to a 1 Mb physical interval.The mutant allele on chr.2DL was identified as Taspl8b,a novel allele of TaSPL8 with a missense mutation in the second exon,which was used to develop a cleaved amplified polymorphic sequence marker.F3 and F4 lines derived from crosses between Jing411 and je0407 were genotyped to investigate interactions between the Tafla1b and Taspl8b alleles.Plants with the Tafla1b/Taspl8a genotype had 58.41%-82.76%smaller flag leaf angles,6.4%-24.9%shorter spikes,and a greater spikelet density(0.382 more spikelets per cm)compared with the wild type.Plants with the Tafla1a/Taspl8b genotype had 52.62%-82.24%smaller flag leaf angles and no differences in plant height or spikelet density compared with the wild type.Tafla1b/Taspl8b plants produced erect leaves with an abnormal lamina joint.The two alleles had dosage effects on ligule formation and flag leaf angle,but no significant effect on thousand-grain weight.The mutant alleles provide novel resources for improvement of wheat plant architecture.展开更多
The parameters of fluorescence induction kinetics and the maximal light-saturated net CO2 assimilation rate (P-sat) of the flag leaves of four cultivars of winter wheat (Triticum aestivum L.) were compared at three di...The parameters of fluorescence induction kinetics and the maximal light-saturated net CO2 assimilation rate (P-sat) of the flag leaves of four cultivars of winter wheat (Triticum aestivum L.) were compared at three different developing stages for the first time. From the blooming stage to the milky stage, the quantum efficiency of PS II photochemistry (F-v/F-m) declined slightly only at the milk stage. The photochemical quenching co-efficient (qP), actual quantum yield of photosystem II (PS II)electron transport (Phi (PSII)) and P-sat decreased substantially (> 15%), while the non-photochemical quenching co-efficient (qN) increased significantly (> 100%). There existed a linear correlation between the Phi (PSII) and the P-sat (r = 0.918). The results indicate that with the senescence of the flag leaves of winter wheat the photosynthetic efficiency including that of the energy transport and the CO2 assimilation significantly decreased.展开更多
[Objective] To provide scientific basis for high phosphorus efficiency cultivation and regulation of rice. [Method] Changbai9 （CB9） and Jijing81 （JJ81） were used as experimental materials for pot experiment, and f...[Objective] To provide scientific basis for high phosphorus efficiency cultivation and regulation of rice. [Method] Changbai9 （CB9） and Jijing81 （JJ81） were used as experimental materials for pot experiment, and five levels of phosphorus nutrient （ Po - P4 ） were set for each variety, the net photosynthesis rate, Chlorophyll Meter Readings （SPAD Readings）, stomatal conductance, transpiration rate, intercellular CO2 concentration, and stomatal limitation were observed and compared between five different phosphorus levels at filling stage. [ Result] The net photosynthesis rate of CB9 reached the highest at P3, and was significantly different from other treatments （P 〈0.05）;the net photosynthesis rate of groups with phosphorus of J J81 were higher than that of the control group,and reached the highest at P,. The SPAD Readings of CB9 and JJ81 all achieved the highest at P3, and stomatal conductance and transpiration rate were all at first increased then decreased with the phosphor- us increased in CB9 and JJ81. With the phosphorus increased, intercellular CO2 concentration of CB9 decreased at first and then increased, while in JJ81 the trend was inversed,but the tendency of intercellular CO2 concentration were opposite to that of stomatal limitation in both culti- vars. [ Conclusion] Appropriate adding phosphorus could improve photosynthetic characteristic of rice flag-leaf,but displayed significant genotypic difference.展开更多
基金supported by the National Key Research and Development Project of China(2022YFD1200700)the Crop Varietal Improvement and Insect Pests Control by Nuclear Radiation,Innovation Program of Chinese Academy of Agricultural Sciences,and the China Agriculture Research System(CARS-03).
文摘Flag leaf angle is one of the key target traits in high yield wheat breeding.A smaller flag leaf angle reduces shading and enables plants to grow at a higher density,which increases yield.Here we identified a mutant,je0407,with an 84.34%-89.35%smaller flag leaf angle compared with the wild type.The mutant also had an abnormal lamina joint and no ligule or auricle.Genetic analysis indicated that the ligule was controlled by two recessive genes,which were mapped to chromosomes 2AS and 2DL.The mutant allele on chromosome 2AS was named Tafla1b,and it was fine mapped to a 1 Mb physical interval.The mutant allele on chr.2DL was identified as Taspl8b,a novel allele of TaSPL8 with a missense mutation in the second exon,which was used to develop a cleaved amplified polymorphic sequence marker.F3 and F4 lines derived from crosses between Jing411 and je0407 were genotyped to investigate interactions between the Tafla1b and Taspl8b alleles.Plants with the Tafla1b/Taspl8a genotype had 58.41%-82.76%smaller flag leaf angles,6.4%-24.9%shorter spikes,and a greater spikelet density(0.382 more spikelets per cm)compared with the wild type.Plants with the Tafla1a/Taspl8b genotype had 52.62%-82.24%smaller flag leaf angles and no differences in plant height or spikelet density compared with the wild type.Tafla1b/Taspl8b plants produced erect leaves with an abnormal lamina joint.The two alleles had dosage effects on ligule formation and flag leaf angle,but no significant effect on thousand-grain weight.The mutant alleles provide novel resources for improvement of wheat plant architecture.
文摘The parameters of fluorescence induction kinetics and the maximal light-saturated net CO2 assimilation rate (P-sat) of the flag leaves of four cultivars of winter wheat (Triticum aestivum L.) were compared at three different developing stages for the first time. From the blooming stage to the milky stage, the quantum efficiency of PS II photochemistry (F-v/F-m) declined slightly only at the milk stage. The photochemical quenching co-efficient (qP), actual quantum yield of photosystem II (PS II)electron transport (Phi (PSII)) and P-sat decreased substantially (> 15%), while the non-photochemical quenching co-efficient (qN) increased significantly (> 100%). There existed a linear correlation between the Phi (PSII) and the P-sat (r = 0.918). The results indicate that with the senescence of the flag leaves of winter wheat the photosynthetic efficiency including that of the energy transport and the CO2 assimilation significantly decreased.
基金Supported by Key Technique Research on Middle and Low Yield Paddy Field Improvement in Jilin Middle Part(20096026)~~
文摘[Objective] To provide scientific basis for high phosphorus efficiency cultivation and regulation of rice. [Method] Changbai9 （CB9） and Jijing81 （JJ81） were used as experimental materials for pot experiment, and five levels of phosphorus nutrient （ Po - P4 ） were set for each variety, the net photosynthesis rate, Chlorophyll Meter Readings （SPAD Readings）, stomatal conductance, transpiration rate, intercellular CO2 concentration, and stomatal limitation were observed and compared between five different phosphorus levels at filling stage. [ Result] The net photosynthesis rate of CB9 reached the highest at P3, and was significantly different from other treatments （P 〈0.05）;the net photosynthesis rate of groups with phosphorus of J J81 were higher than that of the control group,and reached the highest at P,. The SPAD Readings of CB9 and JJ81 all achieved the highest at P3, and stomatal conductance and transpiration rate were all at first increased then decreased with the phosphor- us increased in CB9 and JJ81. With the phosphorus increased, intercellular CO2 concentration of CB9 decreased at first and then increased, while in JJ81 the trend was inversed,but the tendency of intercellular CO2 concentration were opposite to that of stomatal limitation in both culti- vars. [ Conclusion] Appropriate adding phosphorus could improve photosynthetic characteristic of rice flag-leaf,but displayed significant genotypic difference.
