Increasing the planting density of maize is an effective measure to improve its yield.However,plants under high planting density tend to trigger shade avoidance syndrome(SAS),reducing lodging resistance and ultimately...Increasing the planting density of maize is an effective measure to improve its yield.However,plants under high planting density tend to trigger shade avoidance syndrome(SAS),reducing lodging resistance and ultimately yield drop.Phytochrome B(phyB)plays a dominant role in mediating shade avoidance response.This study constructed two hyperactive mutated alleles of maize PHYB1:ZmPHYB1^(Y98F)(mimicking Y104F of AtPHYB)and ZmPHYB1^(Y359F)(mimicking Y361F of AtPHYB).Ectopic expression of ZmPHYB1^(Y98F) and ZmPHYB1^(Y359F) under the control of the ZmPHYB1 promoter in the Arabidopsis phyB-9 background rendered enhanced activity on complementing the phyB-9 related phenotypes compared with ZmPHYB1^(WT).Moreover,similar to the behavior of ZmPHYB1^(WT),ZmPHYB1Y98F and ZmPHYB1^(Y359F) proteins are localized to the nucleus after red light exposure,and could interact with PIF proteins of maize.In addition,expression of ZmPHYB1^(Y98F) and ZmPHYB1^(Y359F) variants under the control of the native ZmPHYB1 promoter attenuated SAS of maize seedlings subjected to simulated shade treatment.It effectively reduced mature maize’s plant height and ear height in field conditions.The results combined demonstrate the utility of ZmPHYB1^(Y98F) and ZmPHYB1^(Y359F) for attenuating SAS and breeding high density-tolerant varieties of maize.展开更多
基金financially supported by the Major Program of Guangdong Basic and Applied Research,China(2019B030302006)the National Natural Science Foundation of China(31801377)the funding from the State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources,China(SKLCUSA-b201801)。
文摘Increasing the planting density of maize is an effective measure to improve its yield.However,plants under high planting density tend to trigger shade avoidance syndrome(SAS),reducing lodging resistance and ultimately yield drop.Phytochrome B(phyB)plays a dominant role in mediating shade avoidance response.This study constructed two hyperactive mutated alleles of maize PHYB1:ZmPHYB1^(Y98F)(mimicking Y104F of AtPHYB)and ZmPHYB1^(Y359F)(mimicking Y361F of AtPHYB).Ectopic expression of ZmPHYB1^(Y98F) and ZmPHYB1^(Y359F) under the control of the ZmPHYB1 promoter in the Arabidopsis phyB-9 background rendered enhanced activity on complementing the phyB-9 related phenotypes compared with ZmPHYB1^(WT).Moreover,similar to the behavior of ZmPHYB1^(WT),ZmPHYB1Y98F and ZmPHYB1^(Y359F) proteins are localized to the nucleus after red light exposure,and could interact with PIF proteins of maize.In addition,expression of ZmPHYB1^(Y98F) and ZmPHYB1^(Y359F) variants under the control of the native ZmPHYB1 promoter attenuated SAS of maize seedlings subjected to simulated shade treatment.It effectively reduced mature maize’s plant height and ear height in field conditions.The results combined demonstrate the utility of ZmPHYB1^(Y98F) and ZmPHYB1^(Y359F) for attenuating SAS and breeding high density-tolerant varieties of maize.
