Tiller is one of the most important agronomic traits which influences quantity and quality of effective panicles and finally influences yield in rice. It is important to understand "static" and "dynamic" informati...Tiller is one of the most important agronomic traits which influences quantity and quality of effective panicles and finally influences yield in rice. It is important to understand "static" and "dynamic" information of the QTLs for tillers in rice. This work was the first time to simultaneously map unconditional and conditional QTLs for tiller numbers at various stages by using single segment substitution lines in rice. Fourteen QTLs for tiller number, distributing on the corresponding substitution segments of chromosomes 1, 2, 3, 4, 6, 7 and 8 were detected. Both the number and the effect of the QTLs for tiller number were various at different stages, from 6 to 9 in the number and from 1.49 to 3.49 in the effect, respectively. Tiller number QTLs expressed in a time order, mainly detected at three stages of 0-7 d, 14-21 d and 35-42 d after transplanting with 6 positive, 9 random and 6 negative expressing QTLs, respectively. Each of the QTLs expressed one time at least during the whole duration of rice. The tiller number at a specific stage was determined by sum of QTL effects estimated by the unconditional method, while the increasing or decreasing number in a given time interval was controlled by the total of QTL effects estimated by the conditional method. These results demonstrated that it is highly effective and accurate for mapping of the QTLs by using single segment substitution lines and the conditional analysis methodology.展开更多
The yield of rice is mostly affected by three factors,namely,panicle number,grain number and grain weight.Variation in panicle and grain numbers is mainly caused by tiller and panicle branches generated from axillary ...The yield of rice is mostly affected by three factors,namely,panicle number,grain number and grain weight.Variation in panicle and grain numbers is mainly caused by tiller and panicle branches generated from axillary meristems(AMs).MOC1 encodes a putative GRAS family nuclear protein that regulates AM formation.Although several alleles of MOC1 have been identified,its variation in germplasm resources remains unclear.In the present study we characterized a novel mocl allele named gnp6 which has a thymine insertion in the coding sequence of the SAW motif in the GRAS domain.This mutation causes arrested branch formation.The SAW motif is necessary for nuclear localization of GNP6/MOC1 where it functions as a transcription factor or co-regulator.Haplotype analysis showed that the coding region of GNP6/MOC1 was conserved without any non-synonymous mutations in 240 rice accessions.However,variation in the promoter region might affect the expression of it and its downstream genes.Joint haplotype analysis of GNP6/MOC1 and MOC3 showed that haplotype combinations H9,H10 and H11,namely MOC1-Hap1 in combination with MOC3-Hap3,MOC3-Hap4 or MOC3-Hap5 could be bred to promote branch formation.These findings will enrich the genetic resources available for rice breeders.展开更多
Following NCI design, the developmental genetic behavior of tiller number (TN) in three-line indica hybrid rice was studied using additive-dominance developmental genetic models and the corresponding statistical metho...Following NCI design, the developmental genetic behavior of tiller number (TN) in three-line indica hybrid rice was studied using additive-dominance developmental genetic models and the corresponding statistical methods. The results showed that dominance effects were predominant for TN. The expression of those additive effects were affected by environment and genotype interaction, but the expression of dominance effects were not affected. Heterosis was the strongest in the middle developmental periods of TN. Additive effects and dominance effects were selectively expressed throughout in the entire tillering developmental stage. Analysis of genetic correlation between TN at different stages and the productive panicles indicated that a close correlation appeared earlier in the populations with higher heterosis than in those with less heterosis. Utilization of heterosis at the middle tillering stage might enhance the final biomass but reduce the percentage of productive panicles.展开更多
Breeding for seedling traits in herbaceous perennial biomass feedstocks that translate into increased biomass yield or quality in established swards could accelerate the development of perennial grass cultivars for bi...Breeding for seedling traits in herbaceous perennial biomass feedstocks that translate into increased biomass yield or quality in established swards could accelerate the development of perennial grass cultivars for bioenergy or forage. In previously reported research, breeding for single large tillers (ST) or multiple tillers (MT, ≥3) six weeks after planting for two generations in big bluestem (Andropogon gerardii Vitman) and switchgrass (Panicum virgatum L.) base populations produced ST and MT populations that differed significantly for seedling and mature plant traits including biomass yield in spaced planted nurseries. Our objective was to evaluate these ST and MT populations in sward trials to determine the effect of these genetic changes on biomass yield and quality when the plants were grown in competitive sward conditions. Big bluestem monocultures of the base, ST, and MT populations were evaluated at three locations in Nebraska in 2001 and 2002 as randomized complete block experiments with four replicates. Switchgrass monocultures of the base, ST, and MT populations were evaluated in 2003, 2004, and 2005 near Mead, NE as a randomized complete block with six replicates. In both big bluestem and switchgrass, the ST and MT populations did not consistently differ from the base population or each other for biomass yield or forage quality. These results demonstrate the importance of evaluating perennial grasses in sward trials and not relying solely on greenhouse-grown plants or space-planted nurseries to develop selection criteria and make selection decisions.展开更多
Tiller number and grain size are important agronomic traits that determine grain yield in rice.Here,we demonstrate that DEFECTIVE TILLER GROWTH 1(DTG1),a member of the casein kinase 1 protein family,exerts a co-regula...Tiller number and grain size are important agronomic traits that determine grain yield in rice.Here,we demonstrate that DEFECTIVE TILLER GROWTH 1(DTG1),a member of the casein kinase 1 protein family,exerts a co-regulatory effect on tiller number and grain size.We identified a single amino acid substitution in DTG1(I357K)that caused a decrease in tiller number and an increase in grain size in NIL-dtg1.Genetic analyses revealed that DTG1 plays a pivotal role in regulation of tillering and grain size.The DTG1^(I357K) allelic variant exhibited robust functionality in suppressing tillering.We show that DTG1 is preferentially expressed in tiller buds and young panicles,and negatively regulates grain size by restricting cell proliferation in spikelet hulls.We further confirm that DTG1 functioned in grain size regulation by directly interacting with Grain Width 2(GW2),a critical grain size regulator in rice.The CRISPR/Cas9-mediated elimination of DTG1 significantly enhanced tiller number and grain size,thereby increasing rice grain yield under field conditions,thus highlighting potential value of DTG1 in rice breeding.展开更多
[Objective] The aim of this study was to compare the morphological char- acteristics of rice (Oryza sativa L.) with different cultivation methods and investigate the dynamics of organ growth and development characte...[Objective] The aim of this study was to compare the morphological char- acteristics of rice (Oryza sativa L.) with different cultivation methods and investigate the dynamics of organ growth and development characteristics of different rice culti- vars. [Method] Based on continuous field observation and destructive sampling over a growing season, detailed organ morphological data were obtained including leaf length, node number, plant height, tiller number, leaf angle, leaf area and specific leaf weight, to compare organ morphological differences among 4 rice cultivars of Baidao (indica), Jinnanfeng (japonica), 9325 (japonica) and 9915 (japonica) with 3 cultivation methods of field planting in Weigang, pot planting in Weigang, and field planting in Jiangpu. [Result] Maximum leaf length of each node gradually increased at the early growth stage and decreased at the later growth stage, the relationship between maximum leaf length and node position can be described by the equations y=a,,-~ and y=ax+b; node number, growth duration, leaf length and plant height of pot planting rice in Weigang were smaller than that of the other two field planting meth- ods; the relationship between plant height and sunshine duration, plant height and GDD (growing degree days) can be described by the equation y=ax+b, 19.23 ℃.d of GDD (≥10 ≥-d) and 8.12 h of sunshine duration were required to increase 1 cm of plant height; plant height, tiller number, and leaf area of Baidao were higher than that of the other 3 laponica rice cultivars, but the specific leaf weight and leaf angle were smaller. [Conclusion] Comparison of morphological characteristic differ- ences among rice cultivars is an important way to select water-saving and drought- tolerant rice varieties. In this study, the experimental results can be integrated into a rice functional-architectural model to simulate rice organ growth dynamics in a three- dimensional space, thereby providing reference for selecting water-saving and drought-tolerant rice cultivars.展开更多
The delta-1-pyrroline-5-carboxylate synthetase(P5CS)gene exercises a protective function in stressed plants.However,the relationship between proline accumulation caused by P5CS and abiotic stress tolerance in plants i...The delta-1-pyrroline-5-carboxylate synthetase(P5CS)gene exercises a protective function in stressed plants.However,the relationship between proline accumulation caused by P5CS and abiotic stress tolerance in plants is not always clear,as P5CS overexpression has been reported to repress plant growth under normal conditions in several reports.We re-evaluated the role of P5CS in drought-tolerant rice breeding by expressing the AtP5CS1 and feedback-inhibition-removed AtP5CS1(AtP5CS1^(F128A))genes under the regulation of an ABA-inducible promoter to avoid the potential side effects of P5CS overexpression under normal conditions.ABA-inducible AtP5CS1 and AtP5CS1^(F128A) increased seedling growth in a nutrient solution(under osmotic stress)and grain yield in pot plants.However,the evidently deleterious effects of AtP5CS1 on grain quality,tiller number,and grain yield in the field indicated the unsuitability of P5CS for drought-tolerance breeding.展开更多
MicroRNAs(miRNAs)are important regulatory elements involved in the regulation of various plant developmental and physiological processes by blocking the expression of target genes.MiR156 and miR529 are two combinatori...MicroRNAs(miRNAs)are important regulatory elements involved in the regulation of various plant developmental and physiological processes by blocking the expression of target genes.MiR156 and miR529 are two combinatorial regulators,which cooperatively target the SQUAMOSA PROMOTER BINDING-LIKE(SPL)family genes.However,there has been no report about the functional conservation and divergence of miR156 and miR529 during plant development to date.In this study,the biological function and relationship of miR156,miR529 and their target Os SPL14 in rice were explored.Overexpression of miR156e or miR529a(miR156e-OE and miR529a-OE)increased the grain size and tiller number but decreased the plant height and panicle length,while an opposite phenotype was observed for their target mimicry(miR156-MIMIC and miR529a-MIMIC)transgenic plants.Stem-loop RT-PCR results revealed ubiquitous expression of miR156 in roots,axillary buds and leaves,while miR529 was preferentially expressed in the panicle.Accordingly,Os SPL14 could be preferentially and precisely cleaved by miR529a in young panicle but by miR156 in vegetative tissues.Transgenic plants generated by the target immune strategy exhibited obvious growth defects upon the blocking of miR156 and/or miR529 function in rice,confirming that both miR156 and miR529 play important roles in controlling rice growth and development.Moreover,the miR156/miR529-Os SPL14 module negatively controlled grain size by regulating the genes associated with grain size and cell cycling,and controlled plant height through a more complicated mechanism.Taken together,our results demonstrate that miR156 and miR529 respectively function dominantly in the vegetative stage and reproductive stage to control rice growth and development by regulating the accumulation of Os SPL14.These findings facilitate a better understanding of the functional conservation and divergence of miR156 and miR529 family in the miRNA combinatorial regulatory network of plants.展开更多
IDEAL PLANT ARCHITECTURE1(IPA1)is a pivotal gene controlling plant architecture and grain yield.However,little is known about the effects of Triticum aestivum SQUAMOSA PROMOTER‐BINDING‐LIKE 14(TaSPL14),an IPA1 ortho...IDEAL PLANT ARCHITECTURE1(IPA1)is a pivotal gene controlling plant architecture and grain yield.However,little is known about the effects of Triticum aestivum SQUAMOSA PROMOTER‐BINDING‐LIKE 14(TaSPL14),an IPA1 ortholog in wheat,on balancing yield traits and its regulatory mechanism in wheat(T.aestivum L.).Here,we determined that the T.aestivum GRAIN WIDTH2(TaGW2)‐TaSPL14 module influences the balance between tiller number and grain weight in wheat.Overexpression of TaSPL14 resulted in a reduced tiller number and increased grain weight,whereas its knockout had the opposite effect,indicating that TaSPL14 negatively regulates tillering while positively regulating grain weight.We further identified TaGW2 as a novel interacting protein of TaSPL14 and confirmed its ability to mediate the ubiquitination and degradation of TaSPL14.Based on our genetic evidence,TaGW2 acts as a positive regulator of tiller number,in addition to its known role as a negative regulator of grain weight,which is opposite to TaSPL14.Moreover,combinations of TaSPL14‐7A and TaGW2‐6A haplotypes exhibit significantly additive effects on tiller number and grain weight in wheat breeding.Our findings provide insight into how the TaGW2‐TaSPL14 module regulates the trade‐off between tiller number and grain weight and its potential application in improving wheat yield.展开更多
Plant architecture is a complex agronomic trait and a major factor of crop yield,which is affected by several important hormones.Strigolactones(SLs)are identified as a new class hormoneinhibiting branching in many pla...Plant architecture is a complex agronomic trait and a major factor of crop yield,which is affected by several important hormones.Strigolactones(SLs)are identified as a new class hormoneinhibiting branching in many plant species and have been shown to be involved in various developmental processes.Genetical and chemical modulation of the SL pathway is recognized as a promising approach to modify plant architecture.However,whether and how the genes involved in the SL pathway could be utilized in breeding still remain elusive.Here,we demonstrate that a partial loss-of-function allele of the SL biosynthesis gene,HIGH TILLERING AND DWARF 1/DWARF17(HTD1/D17),which encodes CAROTENOID CLEAVAGE DIOXYGENASE 7(CCD7),increases tiller number and improves grain yield in rice.We found that the HTD1 gene had been widely utilized and co-selected with Semidwarf 1(SD1),both contributing to the improvement of plant architecture in modern rice varieties since the Green Revolution in the 1960s.Understanding how phytohormone pathway genes regulate plant architecture and how they have been utilized and selected in breeding will lay the foundation for developing the rational approaches toward improving crop yield.展开更多
基金supported by the grants from the National.Basic Research Program of China(2006CB 101700)the National Natural Science Foundation of China(30330370).
文摘Tiller is one of the most important agronomic traits which influences quantity and quality of effective panicles and finally influences yield in rice. It is important to understand "static" and "dynamic" information of the QTLs for tillers in rice. This work was the first time to simultaneously map unconditional and conditional QTLs for tiller numbers at various stages by using single segment substitution lines in rice. Fourteen QTLs for tiller number, distributing on the corresponding substitution segments of chromosomes 1, 2, 3, 4, 6, 7 and 8 were detected. Both the number and the effect of the QTLs for tiller number were various at different stages, from 6 to 9 in the number and from 1.49 to 3.49 in the effect, respectively. Tiller number QTLs expressed in a time order, mainly detected at three stages of 0-7 d, 14-21 d and 35-42 d after transplanting with 6 positive, 9 random and 6 negative expressing QTLs, respectively. Each of the QTLs expressed one time at least during the whole duration of rice. The tiller number at a specific stage was determined by sum of QTL effects estimated by the unconditional method, while the increasing or decreasing number in a given time interval was controlled by the total of QTL effects estimated by the conditional method. These results demonstrated that it is highly effective and accurate for mapping of the QTLs by using single segment substitution lines and the conditional analysis methodology.
基金supported by the National Natural Science Foundation of China(31801324,31171521)the Open Project of Guangxi Key Laboratory of Rice Genetics and Breeding(2018-05-Z06-KF08)China Postdoctoral Science Foundation(2017T100117 and 2019M650902)。
文摘The yield of rice is mostly affected by three factors,namely,panicle number,grain number and grain weight.Variation in panicle and grain numbers is mainly caused by tiller and panicle branches generated from axillary meristems(AMs).MOC1 encodes a putative GRAS family nuclear protein that regulates AM formation.Although several alleles of MOC1 have been identified,its variation in germplasm resources remains unclear.In the present study we characterized a novel mocl allele named gnp6 which has a thymine insertion in the coding sequence of the SAW motif in the GRAS domain.This mutation causes arrested branch formation.The SAW motif is necessary for nuclear localization of GNP6/MOC1 where it functions as a transcription factor or co-regulator.Haplotype analysis showed that the coding region of GNP6/MOC1 was conserved without any non-synonymous mutations in 240 rice accessions.However,variation in the promoter region might affect the expression of it and its downstream genes.Joint haplotype analysis of GNP6/MOC1 and MOC3 showed that haplotype combinations H9,H10 and H11,namely MOC1-Hap1 in combination with MOC3-Hap3,MOC3-Hap4 or MOC3-Hap5 could be bred to promote branch formation.These findings will enrich the genetic resources available for rice breeders.
文摘Following NCI design, the developmental genetic behavior of tiller number (TN) in three-line indica hybrid rice was studied using additive-dominance developmental genetic models and the corresponding statistical methods. The results showed that dominance effects were predominant for TN. The expression of those additive effects were affected by environment and genotype interaction, but the expression of dominance effects were not affected. Heterosis was the strongest in the middle developmental periods of TN. Additive effects and dominance effects were selectively expressed throughout in the entire tillering developmental stage. Analysis of genetic correlation between TN at different stages and the productive panicles indicated that a close correlation appeared earlier in the populations with higher heterosis than in those with less heterosis. Utilization of heterosis at the middle tillering stage might enhance the final biomass but reduce the percentage of productive panicles.
文摘Breeding for seedling traits in herbaceous perennial biomass feedstocks that translate into increased biomass yield or quality in established swards could accelerate the development of perennial grass cultivars for bioenergy or forage. In previously reported research, breeding for single large tillers (ST) or multiple tillers (MT, ≥3) six weeks after planting for two generations in big bluestem (Andropogon gerardii Vitman) and switchgrass (Panicum virgatum L.) base populations produced ST and MT populations that differed significantly for seedling and mature plant traits including biomass yield in spaced planted nurseries. Our objective was to evaluate these ST and MT populations in sward trials to determine the effect of these genetic changes on biomass yield and quality when the plants were grown in competitive sward conditions. Big bluestem monocultures of the base, ST, and MT populations were evaluated at three locations in Nebraska in 2001 and 2002 as randomized complete block experiments with four replicates. Switchgrass monocultures of the base, ST, and MT populations were evaluated in 2003, 2004, and 2005 near Mead, NE as a randomized complete block with six replicates. In both big bluestem and switchgrass, the ST and MT populations did not consistently differ from the base population or each other for biomass yield or forage quality. These results demonstrate the importance of evaluating perennial grasses in sward trials and not relying solely on greenhouse-grown plants or space-planted nurseries to develop selection criteria and make selection decisions.
基金supported by the Sichuan Science and Technology Support Project (2022ZDZX0012,2021YFYZ0016,2023YFN0007,2021YFYZ0027)the National Natural Science Foundation of China (32171966,U23A20180).
文摘Tiller number and grain size are important agronomic traits that determine grain yield in rice.Here,we demonstrate that DEFECTIVE TILLER GROWTH 1(DTG1),a member of the casein kinase 1 protein family,exerts a co-regulatory effect on tiller number and grain size.We identified a single amino acid substitution in DTG1(I357K)that caused a decrease in tiller number and an increase in grain size in NIL-dtg1.Genetic analyses revealed that DTG1 plays a pivotal role in regulation of tillering and grain size.The DTG1^(I357K) allelic variant exhibited robust functionality in suppressing tillering.We show that DTG1 is preferentially expressed in tiller buds and young panicles,and negatively regulates grain size by restricting cell proliferation in spikelet hulls.We further confirm that DTG1 functioned in grain size regulation by directly interacting with Grain Width 2(GW2),a critical grain size regulator in rice.The CRISPR/Cas9-mediated elimination of DTG1 significantly enhanced tiller number and grain size,thereby increasing rice grain yield under field conditions,thus highlighting potential value of DTG1 in rice breeding.
基金Supported by National Natural Science Foundation of China(31101084)Scientific Research Foundation of the Education Ministry for Returned Chinese Scholars~~
文摘[Objective] The aim of this study was to compare the morphological char- acteristics of rice (Oryza sativa L.) with different cultivation methods and investigate the dynamics of organ growth and development characteristics of different rice culti- vars. [Method] Based on continuous field observation and destructive sampling over a growing season, detailed organ morphological data were obtained including leaf length, node number, plant height, tiller number, leaf angle, leaf area and specific leaf weight, to compare organ morphological differences among 4 rice cultivars of Baidao (indica), Jinnanfeng (japonica), 9325 (japonica) and 9915 (japonica) with 3 cultivation methods of field planting in Weigang, pot planting in Weigang, and field planting in Jiangpu. [Result] Maximum leaf length of each node gradually increased at the early growth stage and decreased at the later growth stage, the relationship between maximum leaf length and node position can be described by the equations y=a,,-~ and y=ax+b; node number, growth duration, leaf length and plant height of pot planting rice in Weigang were smaller than that of the other two field planting meth- ods; the relationship between plant height and sunshine duration, plant height and GDD (growing degree days) can be described by the equation y=ax+b, 19.23 ℃.d of GDD (≥10 ≥-d) and 8.12 h of sunshine duration were required to increase 1 cm of plant height; plant height, tiller number, and leaf area of Baidao were higher than that of the other 3 laponica rice cultivars, but the specific leaf weight and leaf angle were smaller. [Conclusion] Comparison of morphological characteristic differ- ences among rice cultivars is an important way to select water-saving and drought- tolerant rice varieties. In this study, the experimental results can be integrated into a rice functional-architectural model to simulate rice organ growth dynamics in a three- dimensional space, thereby providing reference for selecting water-saving and drought-tolerant rice cultivars.
基金supported by the National Natural Science Foundation of China(U21A20209 and 31871640)the key Research Program of the Department of Science and Technology of Sichuan province,China(2021YFYZ0017,2020YJ0350,and 2021YFH0053)the Foundation of International Cooperation in Science and Technology of Chengdu,China(2020-GH02-00027-HZ)。
文摘The delta-1-pyrroline-5-carboxylate synthetase(P5CS)gene exercises a protective function in stressed plants.However,the relationship between proline accumulation caused by P5CS and abiotic stress tolerance in plants is not always clear,as P5CS overexpression has been reported to repress plant growth under normal conditions in several reports.We re-evaluated the role of P5CS in drought-tolerant rice breeding by expressing the AtP5CS1 and feedback-inhibition-removed AtP5CS1(AtP5CS1^(F128A))genes under the regulation of an ABA-inducible promoter to avoid the potential side effects of P5CS overexpression under normal conditions.ABA-inducible AtP5CS1 and AtP5CS1^(F128A) increased seedling growth in a nutrient solution(under osmotic stress)and grain yield in pot plants.However,the evidently deleterious effects of AtP5CS1 on grain quality,tiller number,and grain yield in the field indicated the unsuitability of P5CS for drought-tolerance breeding.
基金supported by the National Natural Science Foundation of China(32101746,31872811)Hubei Provincial Natural Science Foundation of China(2021CFB033,2022CFB393)。
文摘MicroRNAs(miRNAs)are important regulatory elements involved in the regulation of various plant developmental and physiological processes by blocking the expression of target genes.MiR156 and miR529 are two combinatorial regulators,which cooperatively target the SQUAMOSA PROMOTER BINDING-LIKE(SPL)family genes.However,there has been no report about the functional conservation and divergence of miR156 and miR529 during plant development to date.In this study,the biological function and relationship of miR156,miR529 and their target Os SPL14 in rice were explored.Overexpression of miR156e or miR529a(miR156e-OE and miR529a-OE)increased the grain size and tiller number but decreased the plant height and panicle length,while an opposite phenotype was observed for their target mimicry(miR156-MIMIC and miR529a-MIMIC)transgenic plants.Stem-loop RT-PCR results revealed ubiquitous expression of miR156 in roots,axillary buds and leaves,while miR529 was preferentially expressed in the panicle.Accordingly,Os SPL14 could be preferentially and precisely cleaved by miR529a in young panicle but by miR156 in vegetative tissues.Transgenic plants generated by the target immune strategy exhibited obvious growth defects upon the blocking of miR156 and/or miR529 function in rice,confirming that both miR156 and miR529 play important roles in controlling rice growth and development.Moreover,the miR156/miR529-Os SPL14 module negatively controlled grain size by regulating the genes associated with grain size and cell cycling,and controlled plant height through a more complicated mechanism.Taken together,our results demonstrate that miR156 and miR529 respectively function dominantly in the vegetative stage and reproductive stage to control rice growth and development by regulating the accumulation of Os SPL14.These findings facilitate a better understanding of the functional conservation and divergence of miR156 and miR529 family in the miRNA combinatorial regulatory network of plants.
基金financially supported by Beijing Natural Science Foundation (6242032)the Innovation Program of Chinese Academy of Agricultural Sciences (CAAS-CSCB-202401)the Natural Science Foundation of Ningxia Province (2022AAC02056)
文摘IDEAL PLANT ARCHITECTURE1(IPA1)is a pivotal gene controlling plant architecture and grain yield.However,little is known about the effects of Triticum aestivum SQUAMOSA PROMOTER‐BINDING‐LIKE 14(TaSPL14),an IPA1 ortholog in wheat,on balancing yield traits and its regulatory mechanism in wheat(T.aestivum L.).Here,we determined that the T.aestivum GRAIN WIDTH2(TaGW2)‐TaSPL14 module influences the balance between tiller number and grain weight in wheat.Overexpression of TaSPL14 resulted in a reduced tiller number and increased grain weight,whereas its knockout had the opposite effect,indicating that TaSPL14 negatively regulates tillering while positively regulating grain weight.We further identified TaGW2 as a novel interacting protein of TaSPL14 and confirmed its ability to mediate the ubiquitination and degradation of TaSPL14.Based on our genetic evidence,TaGW2 acts as a positive regulator of tiller number,in addition to its known role as a negative regulator of grain weight,which is opposite to TaSPL14.Moreover,combinations of TaSPL14‐7A and TaGW2‐6A haplotypes exhibit significantly additive effects on tiller number and grain weight in wheat breeding.Our findings provide insight into how the TaGW2‐TaSPL14 module regulates the trade‐off between tiller number and grain weight and its potential application in improving wheat yield.
基金This work was supported by the National Key Research and Development Program of China(grant no.2016YFpO101801)National Natural Science Foundation of China(grant nos.91735304,31971921,31601285)+1 种基金Natural Science Foundation of Zhejiang Province(grant no.LR20C130001)Shenzhen Peacock Plan(grant no.KQTD2016113010482651)。
文摘Plant architecture is a complex agronomic trait and a major factor of crop yield,which is affected by several important hormones.Strigolactones(SLs)are identified as a new class hormoneinhibiting branching in many plant species and have been shown to be involved in various developmental processes.Genetical and chemical modulation of the SL pathway is recognized as a promising approach to modify plant architecture.However,whether and how the genes involved in the SL pathway could be utilized in breeding still remain elusive.Here,we demonstrate that a partial loss-of-function allele of the SL biosynthesis gene,HIGH TILLERING AND DWARF 1/DWARF17(HTD1/D17),which encodes CAROTENOID CLEAVAGE DIOXYGENASE 7(CCD7),increases tiller number and improves grain yield in rice.We found that the HTD1 gene had been widely utilized and co-selected with Semidwarf 1(SD1),both contributing to the improvement of plant architecture in modern rice varieties since the Green Revolution in the 1960s.Understanding how phytohormone pathway genes regulate plant architecture and how they have been utilized and selected in breeding will lay the foundation for developing the rational approaches toward improving crop yield.