Low-affinity nitrate transporter genes have been identified in subfamilies 4-8 of the rice nitrate transporter 1(NRT1)/peptide transporter family(NPF),but the OsNPF3 subfamily responsible for nitrate and phytohormone ...Low-affinity nitrate transporter genes have been identified in subfamilies 4-8 of the rice nitrate transporter 1(NRT1)/peptide transporter family(NPF),but the OsNPF3 subfamily responsible for nitrate and phytohormone transport and rice growth and development remains unknown.In this study,we described OsNPF3.1 as an essential nitrate and phytohormone transporter gene for rice tillering and nitrogen utilization efficiency(NUtE).OsNPF3.1 possesses four major haplotypes of its promoter sequence in 517 cultivars,and its expression is positively associated with tiller number.Its expression was higher in the basal part,culm,and leaf blade than in other parts of the plant,and was strongly induced by nitrate,abscisic acid(ABA)and gibberellin 3(GA_3)in the root and shoot of rice.Electrophysiological experiments demonstrated that OsNPF3.1 is a pH-dependent low-affinity nitrate transporter,with rice protoplast uptake assays showing it to be an ABA and GA_3 transporter.OsNPF3.1 overexpression significantly promoted ABA accumulation in the roots and GA accumulation in the basal part of the plant which inhibited axillary bud outgrowth and rice tillering,especially at high nitrate concentrations.The NUtE of OsNPF3.1-overexpressing plants was enhanced under low and medium nitrate concentrations,whereas the NUtE of OsNPF3.1 clustered regularly interspaced short palindromic repeats(CRISPR)plants was increased under high nitrate concentrations.The results indicate that OsNPF3.1 transports nitrate and phytohormones in different rice tissues under different nitrate concentrations.The altered OsNPF3.1 expression improves NUtE in the OsNPF3.1-overexpressing and CRISPR lines at low and high nitrate concentrations,respectively.展开更多
Tillering is a crucial trait closely associated with yield potential and environmental adaptation in cereal crops,regulated by the synergy of endogenous(genetic)and exogenous(environmental)factors.The physiological an...Tillering is a crucial trait closely associated with yield potential and environmental adaptation in cereal crops,regulated by the synergy of endogenous(genetic)and exogenous(environmental)factors.The physiological and molecular regulation of tillering has been intensively studied in rice and wheat.However,tillering research on barley is scarce.This review used the recent advances in bioinformatics to map all known and potential barley tiller development genes with their chromosomal genetic and physical positions.Many of them were mapped for the first time.We also discussed tillering regulation at genetic,physiological,and environmental levels.Moreover,we established a novel link between the genetic control of phytohormones and sugars with tillering.We provided evidence of how environmental cues and cropping systems help optimize the tiller number.This comprehensive review enhances the understanding of barley’s physiological and genetic mechanisms controlling tillering and other developmental traits.展开更多
Increasing tiller number is a target of high-yield rice breeding. Identification of tiller-defect mutants and their corresponding genes is helpful for clarifying the molecular mechanism of rice tillering. Summarizing ...Increasing tiller number is a target of high-yield rice breeding. Identification of tiller-defect mutants and their corresponding genes is helpful for clarifying the molecular mechanism of rice tillering. Summarizing research progress on the two processes of rice tiller formation, namely the formation and growth of axillary meristem, this paper reviews the effects of genetic factors, endogenous hormones, and exogenous environment on rice tillering, finding that multiple molecular mechanisms and signal pathways regulating rice tillering cooperate rice tillering, and discusses future research objectives and application of its regulatory mechanism. Elucidation of theis mechanism will be helpful for breeding high-yielding rice cultivars with ideal plant type via molecular design breeding.展开更多
Tillering is an important agronomic trait for rice grain production. To evaluate yield and tillering response, Liangyoupeijiu(super hybrid rice) was grown in Hunan, China during 2011–2012 under different methods of t...Tillering is an important agronomic trait for rice grain production. To evaluate yield and tillering response, Liangyoupeijiu(super hybrid rice) was grown in Hunan, China during 2011–2012 under different methods of tillage(conventional and no-tillage system) and crop establishment methods(transplanting at a spacing of 20 cm × 20 cm with one seedling per hill and direct seeding at a seeding rate of 22.5 kg ha-1). Our results revealed that, at maximum tillering(Max.) and at maturity(MA) stages, direct seeding(DS) resulted in 22% more tillers than transplanting(TP) irrespective of tillage system. Tiller mortality reached a peak between panicle initiation(PI) and booting(BT) stages, and was 16% higher under conventional tillage(CT) than under no-tillage(NT). Transplanting required 29% more time for the completion of tillering and less for DS. Tillering rate was 43% higher in DS than TP under either CT or NT. There was a positive correlation between panicle number per m2and maximum tiller number per m2, but not panicle-bearing tiller rate. The panicle bearing tiller rate was higher under DS than TP and higher under NT than CT. Tiller dry weight gradually increased up to heading(HD) stage, and was 14% higher under TP than DS. Leaf area(cm2tiller-1) gradually increased from Max. to HD stage and then decreased by 34% in conventional tillage transplanting(CTTP) and 45% in no-tillage transplanting(NTTP) from 12DAH–24DAH(days after heading), but was similar(35%) under DS under either CT or NT. Grain yield was higher under CTTP owing to the larger sink size(heavier panicle, more spikelets in per cm length of panicle) than under DS.展开更多
Physiological responses and changes in growth of Indocalamus decorus Q.H.Dai under different ecological conditions are essential for further understanding growth regulation and adaptive mechanisms and establishing an ...Physiological responses and changes in growth of Indocalamus decorus Q.H.Dai under different ecological conditions are essential for further understanding growth regulation and adaptive mechanisms and establishing an evidence-based management system for optimal growth. In this study, the endogenous hormone content in tillering stem bases, germination of lateral buds, and biomass allocation of this bamboo species in different growth environments were investigated. Among the endogenous hormones in the basal stems of tillers, indole-3-pyruvic acid and zeatin riboside were highly correlated with lateral buds that germinated to form shoots, while gibberellic acid was highly correlated with lateral buds that germinated to form rhizomes. The best lateral bud germination characteristics were achieved with full sun, a density of six plantlets per pot, and watering every 6 days. I. decorus plantlets used different resource allocation strategies depending on treatment. Different ecological factors influenced endogenous hormones in the bamboo stem base,which affected lateral bud germination and biomass allocation.展开更多
Tillering contributes greatly to grain yield in wheat.Investigating the mechanisms of tillering provides a theoretical foundation and genetic resources for the molecular breeding of wheat.The regulation of tillering i...Tillering contributes greatly to grain yield in wheat.Investigating the mechanisms of tillering provides a theoretical foundation and genetic resources for the molecular breeding of wheat.The regulation of tillering is a complex molecular process that involves a multitude of factors.Little is known about the molecular mechanisms in the wheat genome,although progress has been made in rice.Here we review the developmental characteristics of tillers and summarize current knowledge of the roles of endogenous and environmental factors in wheat tillering.We propose directions for future studies and advanced technologies to be used for gene identification and functional studies.展开更多
The moisture-conserving effect of straw mulch-based no-tillage(SMNT)is expected to increase fertile spikes and grain yield in environments with rainfall less than 200 mm.However,the mechanisms under-lying the positive...The moisture-conserving effect of straw mulch-based no-tillage(SMNT)is expected to increase fertile spikes and grain yield in environments with rainfall less than 200 mm.However,the mechanisms under-lying the positive effect of SMNT on wheat tillering are not fully elucidated.A split-plot experiment was designed to investigate the combined effects of SMNT and cultivars on tillering of dryland wheat grown under both dry and favorable climates.Application of SMNT to a cultivar with 1-2 tillers exploited both tillering and kernel-number plasticity,increasing the mean grain yield by 20.5%.This increase was attrib-uted primarily to an increased first-tiller emergence rate resulting from increased N uptake,leaf N con-tent,and N remobilization from tillers to their grain.The second and third tillers,as transient sinks,contributed to the tiller survival rate,which depends on tiller leaf number.The increased total N uptake by SMNT also increased the dry mass yield of tillers and the C:N ratio,reducing the asymmetric compe-tition between main stem and tillers.Owing to these beneficial effects,reduced mitogen-activated pro-tein kinase(MAPK)and abscisic acid signals were observed under SMNT,whereas indole-3-acetic acid(IAA)signals and genes involved in DNA replication and mismatch repair were increased.These signals activated three critical transcription factors(the calmodulin-binding transcription activator,GRAS domain,and cysteine-2/histidine-2 family)and further increased rapid drought response and tiller main-tenance after stem extension.Phenylpropanoid biosynthesis,sphingolipid biosynthesis,and galactose metabolism were most relevant to increased tillering under SMNT because of their critical role in drought response and lignin biosynthesis.Our results suggest that straw mulch-based no-tillage activates rapid drought response and improved wheat tillering by coordinating root N uptake,N remobilization,and asymmetric competition between main stem and tillers.展开更多
In order to study the effects of seed soaking with Paclobutrazol( PP333) on the tillering and physiological characteristics of sugarcane seedlings,sugar cane variety ROC22 was used as experimental material. The effect...In order to study the effects of seed soaking with Paclobutrazol( PP333) on the tillering and physiological characteristics of sugarcane seedlings,sugar cane variety ROC22 was used as experimental material. The effects of seed soaking with different concentrations of PP333 were studied. The tiller number and growth of sugarcane were surveyed at the 6-leaf stage,the physiological indicators such as chlorophyll content,soluble protein content,proline content and peroxidase activity were measured at the 2-leaf,4-leaf,and 6-leaf stages. The results showed that the seed soaking with PP333 can effectively improve the tillering of sugarcane seedlings. The suitable concentration for the tillering of sugarcane and the growth and development of sugarcane was of 50 mg/L; the seed soaking with PP333 significantly increased the chlorophyll,soluble protein,proline,and peroxidase activity of leaves of sugarcane seedlings; the content of chlorophyll and soluble protein in leaves of sugarcane seedlings treated with 90 mg/L PP333 was the highest,and the proline content and peroxidase activity of sugarcane treated with 50 mg/L PP333 were the highest.展开更多
Genotype and agronomic management greatly influence crop growth and grain yield in wheat (Triticum aestivum L.). To ensure sustainable production, seeding rate selection is important to maximize efficiency of every pl...Genotype and agronomic management greatly influence crop growth and grain yield in wheat (Triticum aestivum L.). To ensure sustainable production, seeding rate selection is important to maximize efficiency of every plant. Tillering can allow wheat plants to adjust growth relative to plant density and quality of growing conditions. This research sought to determine a method for assessing tillering of wheat cultivars and develop a standardized approach for characterizing cultivar tillering capacity. Nine cultivars with diverse genetic and phenotypic characteristics were seeded in 2017-2018 at Prosper, ND using various seeding techniques at differing plant spacing arrangements to evaluate tillering habit and spikes plant-1. Cultivars grown at population densities common in grower fields did not express full tillering potential. Spaced-plantings of cultivars promoted cultivar expression of tillering phenotype. The SOFATT (seed only a few, and then thin) method, where average spikes plant-1 was determined from multiple plants sampled from a cultivar grown at spaced-plantings (inter-row and intra-row spacing at 30 ± 12 cm), is recommended to properly assess tillering habits of wheat cultivars. Breeders and researchers can use results from SOFATT evaluations to determine tillering capacity rating for each cultivar based on raw or transformed z-score values for spikes plant-1.展开更多
Tillering and plant height are important components of plant architecture and grain production in rice. We identified a novel high tillering, dwarf and semi-sterile mutant, as named tdr1 in a rice maintainer line E20 ...Tillering and plant height are important components of plant architecture and grain production in rice. We identified a novel high tillering, dwarf and semi-sterile mutant, as named tdr1 in a rice maintainer line E20 derived from the cross between between IR68888B and Luxiang 90. The investigation of tiller dynamic in the tdr1 line displayed 3 different phases: rapid increasing of tillers in the vegetative growth stage, producing no new tillers in the transition stage from the vegetative growth to reproductive growth, and regeneration of new tillers after heading. The assay of hormones showed the significant reduction of brassinolide level and no change of the levels of gibberellic acid, cytokinin and strigolactone in the tdr1 line. Genetic analysis indicated the phenotype of high tillering, dwarfism and semi-sterility is controlled by a recessive gene in several different segregation populations. The TDR1 gene was mapped in the 105 kb interval between RM3288 and RM6590 on chromosome 4. Cloning of TDR1 gene would provide a new opportunity to uncover the molecular mechanism of the development of plant height and tiller in rice.展开更多
[Objectives]This study was conducted to discuss the effects of tillering law and its controlling factors on the growth of Ophiopogon japonicus cv.[Methods]With O.japonicus cv as an experimental material,its average nu...[Objectives]This study was conducted to discuss the effects of tillering law and its controlling factors on the growth of Ophiopogon japonicus cv.[Methods]With O.japonicus cv as an experimental material,its average number of tillers,proliferation coefficient,total number of tillers,death number,germination index,germination rate,fresh root weight,root volume and survival rate were determined.[Results] The reproductive ability of the NAA treatments was significantly higher than that of the 6-BA treatments,and the average tillering capacity of the 5 mg/L NAA treatment was significantly higher,90% higher than that of the CK.The proliferation coefficient of O.japonicus cv was significantly better in the NAA treatments than in the 6-BA treatments,and the 5 mg/L-NAA treatment was more significant.The NAA treatments showed total numbers of tillers significantly higher than those of the 6-BA treatments,and exhibited significantly reduced deaths.The 1 mg/L NAA and 10 mg/L 6-BA experimental groups had the strongest germination-promoting effects on O.japonicus cv,which were significantly different from those of other experimental groups,and were 92% and 95% higher than that of the CK,respectively.As to the germination rate indicator of O.japonicus cv,the 1 mg/L NAA and 10 mg/L 6-BA experimental groups exhibited the highest values,which increased by 48% and 43%,respectively,compared with the CK.The 6-BA treatments significantly improved the root growth of O.japonicus cv compared with the NAA treatments,and they significantly promoted root volume of O.japonicus cv.The survival rate of O.japonicus cv treated with hormone NAA was 23.3% higher than that of the 6-BA treatment group.[Conclusions] This study provide a theoretical basis for improving the reproductive ability of O.japonicus cv and expanding its commercial production.展开更多
Tillering is an important agronomic trait of rice(Oryza sativa)that affects the number of effective panicles,thereby affecting yields.The phytohormone auxin plays a key role in tillering.Here we identified the high ti...Tillering is an important agronomic trait of rice(Oryza sativa)that affects the number of effective panicles,thereby affecting yields.The phytohormone auxin plays a key role in tillering.Here we identified the high tillering and semi-dwarf 1(htsd1)mutant with auxin-deficiency root characteristics,such as shortened lateral roots,reduced lateral root density,and enlarged root angles.htsd1 showed reduced sensitivity to auxin,but the external application of indole-3-acetic acid(IAA)inhibited its tillering.We identified the mutated gene in htsd1 as AUXIN1(OsAUX1,LOC_Os01g63770),which encodes an auxin influx transporter.The promoter sequence of OsAUX1 contains many SQUAMOSA PROMOTER BINDING PROTEIN-LIKE(SPL)binding sites,and we demonstrated that SPL7 binds to the OsAUX1 promoter.TEOSINTE BRANCHED1(OsTB1),a key gene that negatively regulates tillering,was significantly downregulated in htsd1.Tillering was enhanced in the OsTB1 knockout mutant,and the external application of IAA inhibited tiller elongation in this mutant.Overexpressing OsTB1 restored the multi-tiller phenotype of htsd1.These results suggest that SPL7 directly binds to the OsAUX1 promoter and regulates tillering in rice by altering OsTB1 expression to modulate auxin signaling.展开更多
Rice tillering,a key architecture trait determ ining grain yield,is highly regulated by a class of newly identified phytohorm ones,strigolactones(SLs).How ever,the whole SL signaling pathw ay from the receptor to dow ...Rice tillering,a key architecture trait determ ining grain yield,is highly regulated by a class of newly identified phytohorm ones,strigolactones(SLs).How ever,the whole SL signaling pathw ay from the receptor to dow nstream transcription factors to finally inhibit tillering remains unrevealed.In this study,we first found that brassinosteroids(BRs)strongly enhance tillering by prom oting bud outgrow th in rice,which is largely different from the function of BRs in Arabidopsis.Genetic and biochem ical analyses indicated that both the SL and BR signaling pathw ays control rice tillering by regulating the stability of D53 and/or the OsBZR1 RLA1-DLT module,a transcriptional complex in the rice BR signaling pathway.We further found that D53 interacts with OsBZR1 to inhibit the expression of FC1,a local inhibitor of tillering,and that this inhibition depends on direct DNA binding by OsBZR1,which recruits D53 to the FC1 promoter in rice buds.Taken together,these findings uncover a mechanism illustrating how SLs and BRs coordinately regulate rice tillering via the early responsive gene FC1.展开更多
Rice tillering is an important agronomic trait affecting grain yield.Here,we identified a high-tillering mutant tillering20(t20),which could be restored to the wild type by treatment with the strigolactone(SL)analog r...Rice tillering is an important agronomic trait affecting grain yield.Here,we identified a high-tillering mutant tillering20(t20),which could be restored to the wild type by treatment with the strigolactone(SL)analog rac-GR24.T20 encodes a chloroplast ζ-carotene isomerase(Z-ISO),which is involved in the biosynthesis of ca-rotenoids and their metabolites,SL and abscisic acid(ABA).The t20 mutant has reduced SL and ABA,raising the question of how SL and ABA biosynthesis is coordinated,and whether they have overlapping functions in tillering.We discovered that rac-GR24 stimulated T20 expression and enhanced all-trans-p-carotene biosynthesis.Importantly,rac-GR24 also stimulated expression of Oryza sativa 9-CIS-EPOXY-CAROTENOID DIOXYGENASE 1(OsNCED1)through induction of Oryza sativa HOMEOBOX12(0sHOX12),promoting ABA biosynthesis in shoot base.On the other hand,ABA treatment significantly repressed SL biosynthesis and the ABA biosynthetic mutants displayed elevated SL biosynthesis.ABA treatment reduced the number of basal tillers in both t20 and wild-type plants.Furthermore,while ABA-deficient mu-tants aba1 and aba2 had the same number of basal tillers as wild type,they had more unproductive upper tillers at maturity.This work demonstrates complex interactions in the biosynthesis of carotenoid,SLs and ABA,and reveals a role for ABA in the regulation of rice tillering.展开更多
Multiple genes and microRNAs(miRNAs)improve grain yield by promoting tillering.MiR319s are known to regulate several aspects of plant development;however,whether miR319s are essential for tillering regulation remains ...Multiple genes and microRNAs(miRNAs)improve grain yield by promoting tillering.MiR319s are known to regulate several aspects of plant development;however,whether miR319s are essential for tillering regulation remains unclear.Here,we report that miR319 is highly expressed in the basal part of rice plant at different development stages.The miR319 knockdown line Short Tandem Target Mimic 319(STTM319)showed higher tiller bud length in seedlings under low nitrogen(N)condition and higher tiller bud number under high N condition compared with the miR319a-overexpression line.Through targets prediction,we identified OsTCP21 and OsGAmyb as downstream targets of miR319.Moreover,OsTCP21 and OsGAmyb overexpression lines and STTM319 had increased tiller bud length and biomass,whereas both were decreased in OsTCP21 and OsGAmyb knockout lines and OE319a.These data suggest that miR319 regulates rice tiller bud development and tillering through targeting OsTCP21 and OsGAmyb.Notably,the tiller number and grain yield increased in STTM319 and overexpression lines of OsTCP21 and OsGAmyb but decreased in OE319a and knockout lines of OsTCP21 and OsGAmyb.Taken together,our findings indicate that miR319s negatively affect tiller number and grain yield by targeting OsTCP21 and OsGAmyb,revealing a novel function for miR319 in rice.展开更多
Tillering is a major determinant of rice plant architecture and grain yield.Here,we report that depletion of rice OsNRPD1a and OsNRPD1b,two orthologs of the largest subunit of RNA polymerase IV,leads to a high-tilleri...Tillering is a major determinant of rice plant architecture and grain yield.Here,we report that depletion of rice OsNRPD1a and OsNRPD1b,two orthologs of the largest subunit of RNA polymerase IV,leads to a high-tillering phenotype,in addition to dwarfism and smaller panicles.OsNRPD1a and OsNRPD1b are required for the production of 24-nt small interfering RNAs that direct DNA methylation at transposable elements(TEs)including miniature inverted-repeat TEs(MITEs).Interestingly,many genes are regulated either positively or negatively by TE methylation.Among them,OsMIR156d and OsMIR156j,which promote rice tillering,are repressed by CHH methylation at two MITEs in the promoters.By contrast,D14,which suppresses rice tillering,is activated by CHH methylation at an MITE in its downstream.Our findings reveal regulation of rice tillering by RNA-directed DNA methylation at MITEs and provide potential targets for agronomic trait enhancement through epigenome editing.展开更多
Plant architecture determines grain production in rice(Oryza sativa) and is affected by important agronomic traits such as tillering,plant height,and panicle morphology.Many key genes involved in controlling the initi...Plant architecture determines grain production in rice(Oryza sativa) and is affected by important agronomic traits such as tillering,plant height,and panicle morphology.Many key genes involved in controlling the initiation and outgrowth of axillary buds,the elongation of stems,and the architecture of inflorescences have been isolated and analyzed.Previous studies have shown that SiPf40,which was identified from a foxtail millet(Setaria italica) immature seed cDNA library,causes extra branches and tillers in SiPf40-transgenic tobacco and foxtail millet,respectively.To reconfirm its function,we generated transgenic rice plants overexpressing SiPf40 under the control of the ubiquitin promoter.SiPf40-overexpressing transgenic plants have a greater tillering number and a wider tiller angle than wild-type plants.Their root architecture is modified by the promotion of lateral root development,and the distribution of xylem and phloem in the vascular bundle is affected.Analysis of hormone levels showed that the ratios of indole-3-acetic acid/zeatin(IAA/ZR) and IAA/gibberellic acid(IAA/GA) decreased in SiPf40-transgenic plants compared with wild-type plants.These findings strongly suggest that SiPf40 plays an important role in plant architecture.展开更多
The emission of microwave sulfur lamp is mainly composed of visible light. The sulfur lamp, producing little infrared radiation, has high efficiency, long duration of illumination and less energy consumption. In order...The emission of microwave sulfur lamp is mainly composed of visible light. The sulfur lamp, producing little infrared radiation, has high efficiency, long duration of illumination and less energy consumption. In order to probe the agricultural application of the lamp, experiments were carried out with wheat (cv. Yangmai 158) to emphatically study illuminating effects of xenon or sulfur lamp on tillering, jointing and net photosynthetic rate during tillering and jointing periods. Results indicated that there is almost no difference in net photosynthetic rate of wheat leaves growing under different lamps. Xenon lamp significantly advanced the time of jointing, decreased number of tillers, number of total leaves per plant and leaf size, as well as inhibited root growth. In contrast with xenon lamp, sulfur lamp evidently delays the time of heading and grain maturation, increased number of heads per plant, head length, total number of grains per plant, head weight and total grain weight per plant,展开更多
Nitrogen(N)fertilization is necessary for obtaining high rice yield.But excessive N fertilizer reduces rice plant N efficiency and causes negative effects such as environmental pollution.In this study,we assembled key...Nitrogen(N)fertilization is necessary for obtaining high rice yield.But excessive N fertilizer reduces rice plant N efficiency and causes negative effects such as environmental pollution.In this study,we assembled key genes involved in different nodes of N pathways to boost nitrate and ammonium uptake and assimilation,and to strengthen amino acid utilization to increase grain yield and nitrogen use efficiency(NUE)in rice.The combinations OsNPF8.9a×OsNR2,OsAMT1;2×OsGS1;2×OsAS1,and OsGS2×OsAS2×OsANT3 optimized nitrate assimilation,ammonium conversion,and N reutilization,respectively.In co-overexpressing rice lines obtained by co-transformation,the tiller number,biomass,and grain yield per plant of the OsAMT1;2×OsGS1;2×OsAS1-overexpressing line exceeded those of wild-type ZH11,the OsNPF8.9a×OsNR2×OsGS1;2×OsAS1-overexpressing line,and the OsGS2×OsAS2×OsANT3-overexpressing line.The glutamine synthase activity,free amino acids,and nitrogen utilization efficiency(NUt E)of the OsAMT1;2×OsGS1;2×OsAS1-overexpressing line exceeded those of ZH11 and other lines that combined key genes.N influx efficiency was increased in the OsAMT1;2×OsGS1;2×OsAS1-overexpressing line and OsNPF8.9a×OsNR2×OsGS1;2×OsAS1-overexpressing line under a low ammonium and a low nitrate treatment,respectively.We propose that combining overexpression of OsAMT1;2,OsGS1;2,and OsAS1 is a promising breeding strategy for systematically increasing rice grain yield and NUE by focusing on key nodes in the N pathway.展开更多
Genetic improvement has promoted wheat’s grain yield and nitrogen use efficiency(NUE)during the past decades.Therefore,the current wheat cultivars exhibit higher grain yield and NUE than previous cultivars in the Yan...Genetic improvement has promoted wheat’s grain yield and nitrogen use efficiency(NUE)during the past decades.Therefore,the current wheat cultivars exhibit higher grain yield and NUE than previous cultivars in the Yangtze River Basin,China since the 2000s.However,the critical traits and mechanisms of the increased grain yield and NUE remain unknown.This study explores the mechanisms underlying these new cultivars’increased grain yield and NUE by studying 21 local cultivars cultivated for three growing seasons from 2016 to 2019.Significantly positive correlations were observed between grain yield and NUE in the three years.The cultivars were grouped into high(HH),medium(MM),and low(LL)grain yield and NUE groups.The HH group exhibited significantly high grain yield and NUE.High grain yield was attributed to more effective ears by high tiller fertility and greater single-spike yield by increasing post-anthesis single-stem biomass.Compared to other groups,the HH group demonstrated a longer leaf stay-green ability and a greater flag leaf photosynthetic rate after anthesis.It also showed higher N accumulation at pre-anthesis,which contributed to increasing N accumulation per stem,including stem and leaf sheath,leaf blade,and unit leaf area at pre-anthesis,and promoting N uptake efficiency,the main contribution of high NUE.Moreover,tiller fertility was positively related to N accumulation per stem,N accumulation per unit leaf area,leaf stay-green ability,and flag leaf photosynthetic rate,which indicates that improving tiller fertility promoted N uptake,leaf N accumulation,and photosynthetic ability,thereby achieving synchronous improvements in grain yield and NUE.Therefore,tiller fertility is proposed as an important kernel indicator that can be used in the breeding and management of cultivars to improve agricultural efficiency and sustainability.展开更多
基金supported by the the Guizhou Provincial Excellent Young Talents Project of Science and Technology,China(YQK(2023)002)the Guizhou Provincial Science and Technology Projects,China((2022)Key 008)+2 种基金the Guizhou Provincial Science and Technology Support Plan,China((2022)Key 026)the Key Laboratory of Molecular Breeding for Grain and Oil Crops in Guizhou Province,China((2023)008)the Key Laboratory of Functional Agriculture of Guizhou Provincial Higher Education Institutions,China((2023)007)。
文摘Low-affinity nitrate transporter genes have been identified in subfamilies 4-8 of the rice nitrate transporter 1(NRT1)/peptide transporter family(NPF),but the OsNPF3 subfamily responsible for nitrate and phytohormone transport and rice growth and development remains unknown.In this study,we described OsNPF3.1 as an essential nitrate and phytohormone transporter gene for rice tillering and nitrogen utilization efficiency(NUtE).OsNPF3.1 possesses four major haplotypes of its promoter sequence in 517 cultivars,and its expression is positively associated with tiller number.Its expression was higher in the basal part,culm,and leaf blade than in other parts of the plant,and was strongly induced by nitrate,abscisic acid(ABA)and gibberellin 3(GA_3)in the root and shoot of rice.Electrophysiological experiments demonstrated that OsNPF3.1 is a pH-dependent low-affinity nitrate transporter,with rice protoplast uptake assays showing it to be an ABA and GA_3 transporter.OsNPF3.1 overexpression significantly promoted ABA accumulation in the roots and GA accumulation in the basal part of the plant which inhibited axillary bud outgrowth and rice tillering,especially at high nitrate concentrations.The NUtE of OsNPF3.1-overexpressing plants was enhanced under low and medium nitrate concentrations,whereas the NUtE of OsNPF3.1 clustered regularly interspaced short palindromic repeats(CRISPR)plants was increased under high nitrate concentrations.The results indicate that OsNPF3.1 transports nitrate and phytohormones in different rice tissues under different nitrate concentrations.The altered OsNPF3.1 expression improves NUtE in the OsNPF3.1-overexpressing and CRISPR lines at low and high nitrate concentrations,respectively.
基金the National Key R&D Program of China(2018YFD1000706)the Key Research Project of Science and Technology Department of Zhejiang Province,China(2021C02064-3)the Jiangsu Collaborative Innovation Center for Modern Crop Production,China.
文摘Tillering is a crucial trait closely associated with yield potential and environmental adaptation in cereal crops,regulated by the synergy of endogenous(genetic)and exogenous(environmental)factors.The physiological and molecular regulation of tillering has been intensively studied in rice and wheat.However,tillering research on barley is scarce.This review used the recent advances in bioinformatics to map all known and potential barley tiller development genes with their chromosomal genetic and physical positions.Many of them were mapped for the first time.We also discussed tillering regulation at genetic,physiological,and environmental levels.Moreover,we established a novel link between the genetic control of phytohormones and sugars with tillering.We provided evidence of how environmental cues and cropping systems help optimize the tiller number.This comprehensive review enhances the understanding of barley’s physiological and genetic mechanisms controlling tillering and other developmental traits.
基金supported by the National Natural Science Foundation of China (32071993, 32188102, 31971872, 31861143006,U2004204)Key Agricultural Technology Project(NK2022010302)。
文摘Increasing tiller number is a target of high-yield rice breeding. Identification of tiller-defect mutants and their corresponding genes is helpful for clarifying the molecular mechanism of rice tillering. Summarizing research progress on the two processes of rice tiller formation, namely the formation and growth of axillary meristem, this paper reviews the effects of genetic factors, endogenous hormones, and exogenous environment on rice tillering, finding that multiple molecular mechanisms and signal pathways regulating rice tillering cooperate rice tillering, and discusses future research objectives and application of its regulatory mechanism. Elucidation of theis mechanism will be helpful for breeding high-yielding rice cultivars with ideal plant type via molecular design breeding.
基金financial supportprovided by the National Natural Science Foundation of China project, No. 311712494the financial support provided by NATP, BARC, Dhaka, Bangladesh
文摘Tillering is an important agronomic trait for rice grain production. To evaluate yield and tillering response, Liangyoupeijiu(super hybrid rice) was grown in Hunan, China during 2011–2012 under different methods of tillage(conventional and no-tillage system) and crop establishment methods(transplanting at a spacing of 20 cm × 20 cm with one seedling per hill and direct seeding at a seeding rate of 22.5 kg ha-1). Our results revealed that, at maximum tillering(Max.) and at maturity(MA) stages, direct seeding(DS) resulted in 22% more tillers than transplanting(TP) irrespective of tillage system. Tiller mortality reached a peak between panicle initiation(PI) and booting(BT) stages, and was 16% higher under conventional tillage(CT) than under no-tillage(NT). Transplanting required 29% more time for the completion of tillering and less for DS. Tillering rate was 43% higher in DS than TP under either CT or NT. There was a positive correlation between panicle number per m2and maximum tiller number per m2, but not panicle-bearing tiller rate. The panicle bearing tiller rate was higher under DS than TP and higher under NT than CT. Tiller dry weight gradually increased up to heading(HD) stage, and was 14% higher under TP than DS. Leaf area(cm2tiller-1) gradually increased from Max. to HD stage and then decreased by 34% in conventional tillage transplanting(CTTP) and 45% in no-tillage transplanting(NTTP) from 12DAH–24DAH(days after heading), but was similar(35%) under DS under either CT or NT. Grain yield was higher under CTTP owing to the larger sink size(heavier panicle, more spikelets in per cm length of panicle) than under DS.
基金financially supported by the Fundamental Research Funds for the Central Nonprofit Research Institution of CAF(CAFYBB2014QA038)Natural Science Foundation of Zhejiang Province(LY14C030008)Science and Technology Planning Project of Zhejiang Province(2014F10047)
文摘Physiological responses and changes in growth of Indocalamus decorus Q.H.Dai under different ecological conditions are essential for further understanding growth regulation and adaptive mechanisms and establishing an evidence-based management system for optimal growth. In this study, the endogenous hormone content in tillering stem bases, germination of lateral buds, and biomass allocation of this bamboo species in different growth environments were investigated. Among the endogenous hormones in the basal stems of tillers, indole-3-pyruvic acid and zeatin riboside were highly correlated with lateral buds that germinated to form shoots, while gibberellic acid was highly correlated with lateral buds that germinated to form rhizomes. The best lateral bud germination characteristics were achieved with full sun, a density of six plantlets per pot, and watering every 6 days. I. decorus plantlets used different resource allocation strategies depending on treatment. Different ecological factors influenced endogenous hormones in the bamboo stem base,which affected lateral bud germination and biomass allocation.
基金supported by the Major Research Plan of the National Natural Science Foundation of China (91935302)the National Natural Science Foundation of China (31971812)Major Basic Research Project of Shandong Natural Science Foundation (ZR2019ZD15)。
文摘Tillering contributes greatly to grain yield in wheat.Investigating the mechanisms of tillering provides a theoretical foundation and genetic resources for the molecular breeding of wheat.The regulation of tillering is a complex molecular process that involves a multitude of factors.Little is known about the molecular mechanisms in the wheat genome,although progress has been made in rice.Here we review the developmental characteristics of tillers and summarize current knowledge of the roles of endogenous and environmental factors in wheat tillering.We propose directions for future studies and advanced technologies to be used for gene identification and functional studies.
基金financial support from the Sichuan Province Science and Technology Support Program (2021YJ0504,2021YFYZ0002)National Key Research and Development Program of China (2016YFD0300406)+1 种基金Special Fund for Agro-scientific Research in the Public Interest (20150312705)the Crops Breeding Project in Sichuan Province (2016NYZ0051,22ZDZX0018)
文摘The moisture-conserving effect of straw mulch-based no-tillage(SMNT)is expected to increase fertile spikes and grain yield in environments with rainfall less than 200 mm.However,the mechanisms under-lying the positive effect of SMNT on wheat tillering are not fully elucidated.A split-plot experiment was designed to investigate the combined effects of SMNT and cultivars on tillering of dryland wheat grown under both dry and favorable climates.Application of SMNT to a cultivar with 1-2 tillers exploited both tillering and kernel-number plasticity,increasing the mean grain yield by 20.5%.This increase was attrib-uted primarily to an increased first-tiller emergence rate resulting from increased N uptake,leaf N con-tent,and N remobilization from tillers to their grain.The second and third tillers,as transient sinks,contributed to the tiller survival rate,which depends on tiller leaf number.The increased total N uptake by SMNT also increased the dry mass yield of tillers and the C:N ratio,reducing the asymmetric compe-tition between main stem and tillers.Owing to these beneficial effects,reduced mitogen-activated pro-tein kinase(MAPK)and abscisic acid signals were observed under SMNT,whereas indole-3-acetic acid(IAA)signals and genes involved in DNA replication and mismatch repair were increased.These signals activated three critical transcription factors(the calmodulin-binding transcription activator,GRAS domain,and cysteine-2/histidine-2 family)and further increased rapid drought response and tiller main-tenance after stem extension.Phenylpropanoid biosynthesis,sphingolipid biosynthesis,and galactose metabolism were most relevant to increased tillering under SMNT because of their critical role in drought response and lignin biosynthesis.Our results suggest that straw mulch-based no-tillage activates rapid drought response and improved wheat tillering by coordinating root N uptake,N remobilization,and asymmetric competition between main stem and tillers.
基金Supported by Project of National Natural Science Foundation(31501362)Natural Science Foundation Project of Guangxi(2014GXNSFBA118289,2014GXNSFAA118090)
文摘In order to study the effects of seed soaking with Paclobutrazol( PP333) on the tillering and physiological characteristics of sugarcane seedlings,sugar cane variety ROC22 was used as experimental material. The effects of seed soaking with different concentrations of PP333 were studied. The tiller number and growth of sugarcane were surveyed at the 6-leaf stage,the physiological indicators such as chlorophyll content,soluble protein content,proline content and peroxidase activity were measured at the 2-leaf,4-leaf,and 6-leaf stages. The results showed that the seed soaking with PP333 can effectively improve the tillering of sugarcane seedlings. The suitable concentration for the tillering of sugarcane and the growth and development of sugarcane was of 50 mg/L; the seed soaking with PP333 significantly increased the chlorophyll,soluble protein,proline,and peroxidase activity of leaves of sugarcane seedlings; the content of chlorophyll and soluble protein in leaves of sugarcane seedlings treated with 90 mg/L PP333 was the highest,and the proline content and peroxidase activity of sugarcane treated with 50 mg/L PP333 were the highest.
文摘Genotype and agronomic management greatly influence crop growth and grain yield in wheat (Triticum aestivum L.). To ensure sustainable production, seeding rate selection is important to maximize efficiency of every plant. Tillering can allow wheat plants to adjust growth relative to plant density and quality of growing conditions. This research sought to determine a method for assessing tillering of wheat cultivars and develop a standardized approach for characterizing cultivar tillering capacity. Nine cultivars with diverse genetic and phenotypic characteristics were seeded in 2017-2018 at Prosper, ND using various seeding techniques at differing plant spacing arrangements to evaluate tillering habit and spikes plant-1. Cultivars grown at population densities common in grower fields did not express full tillering potential. Spaced-plantings of cultivars promoted cultivar expression of tillering phenotype. The SOFATT (seed only a few, and then thin) method, where average spikes plant-1 was determined from multiple plants sampled from a cultivar grown at spaced-plantings (inter-row and intra-row spacing at 30 ± 12 cm), is recommended to properly assess tillering habits of wheat cultivars. Breeders and researchers can use results from SOFATT evaluations to determine tillering capacity rating for each cultivar based on raw or transformed z-score values for spikes plant-1.
文摘Tillering and plant height are important components of plant architecture and grain production in rice. We identified a novel high tillering, dwarf and semi-sterile mutant, as named tdr1 in a rice maintainer line E20 derived from the cross between between IR68888B and Luxiang 90. The investigation of tiller dynamic in the tdr1 line displayed 3 different phases: rapid increasing of tillers in the vegetative growth stage, producing no new tillers in the transition stage from the vegetative growth to reproductive growth, and regeneration of new tillers after heading. The assay of hormones showed the significant reduction of brassinolide level and no change of the levels of gibberellic acid, cytokinin and strigolactone in the tdr1 line. Genetic analysis indicated the phenotype of high tillering, dwarfism and semi-sterility is controlled by a recessive gene in several different segregation populations. The TDR1 gene was mapped in the 105 kb interval between RM3288 and RM6590 on chromosome 4. Cloning of TDR1 gene would provide a new opportunity to uncover the molecular mechanism of the development of plant height and tiller in rice.
文摘[Objectives]This study was conducted to discuss the effects of tillering law and its controlling factors on the growth of Ophiopogon japonicus cv.[Methods]With O.japonicus cv as an experimental material,its average number of tillers,proliferation coefficient,total number of tillers,death number,germination index,germination rate,fresh root weight,root volume and survival rate were determined.[Results] The reproductive ability of the NAA treatments was significantly higher than that of the 6-BA treatments,and the average tillering capacity of the 5 mg/L NAA treatment was significantly higher,90% higher than that of the CK.The proliferation coefficient of O.japonicus cv was significantly better in the NAA treatments than in the 6-BA treatments,and the 5 mg/L-NAA treatment was more significant.The NAA treatments showed total numbers of tillers significantly higher than those of the 6-BA treatments,and exhibited significantly reduced deaths.The 1 mg/L NAA and 10 mg/L 6-BA experimental groups had the strongest germination-promoting effects on O.japonicus cv,which were significantly different from those of other experimental groups,and were 92% and 95% higher than that of the CK,respectively.As to the germination rate indicator of O.japonicus cv,the 1 mg/L NAA and 10 mg/L 6-BA experimental groups exhibited the highest values,which increased by 48% and 43%,respectively,compared with the CK.The 6-BA treatments significantly improved the root growth of O.japonicus cv compared with the NAA treatments,and they significantly promoted root volume of O.japonicus cv.The survival rate of O.japonicus cv treated with hormone NAA was 23.3% higher than that of the 6-BA treatment group.[Conclusions] This study provide a theoretical basis for improving the reproductive ability of O.japonicus cv and expanding its commercial production.
基金This work was supported by the National Key Research and Development Program of China(2022YFD1201600)the National Natural Science Foundation of China(32171964)the Science Fund for Creative Research Groups of Chongqing,China(cstc2021jcyj-cxttX0004)。
文摘Tillering is an important agronomic trait of rice(Oryza sativa)that affects the number of effective panicles,thereby affecting yields.The phytohormone auxin plays a key role in tillering.Here we identified the high tillering and semi-dwarf 1(htsd1)mutant with auxin-deficiency root characteristics,such as shortened lateral roots,reduced lateral root density,and enlarged root angles.htsd1 showed reduced sensitivity to auxin,but the external application of indole-3-acetic acid(IAA)inhibited its tillering.We identified the mutated gene in htsd1 as AUXIN1(OsAUX1,LOC_Os01g63770),which encodes an auxin influx transporter.The promoter sequence of OsAUX1 contains many SQUAMOSA PROMOTER BINDING PROTEIN-LIKE(SPL)binding sites,and we demonstrated that SPL7 binds to the OsAUX1 promoter.TEOSINTE BRANCHED1(OsTB1),a key gene that negatively regulates tillering,was significantly downregulated in htsd1.Tillering was enhanced in the OsTB1 knockout mutant,and the external application of IAA inhibited tiller elongation in this mutant.Overexpressing OsTB1 restored the multi-tiller phenotype of htsd1.These results suggest that SPL7 directly binds to the OsAUX1 promoter and regulates tillering in rice by altering OsTB1 expression to modulate auxin signaling.
基金This work was supported by grants from NNSFC(31430046 to X.W.),NKRDP(2016YFD0100403 to S.S.,2016YFD0100700 to Z.F.),ICPNNSFC(31661143024 to X.W.),MAITP(0120150092 to X.W.)School Independent Scientific and Technological Innovation Foundation and Research Startup Foundation of Huazhong Agricultural University(2662015PY020,2014RC002 to X.W.).
文摘Rice tillering,a key architecture trait determ ining grain yield,is highly regulated by a class of newly identified phytohorm ones,strigolactones(SLs).How ever,the whole SL signaling pathw ay from the receptor to dow nstream transcription factors to finally inhibit tillering remains unrevealed.In this study,we first found that brassinosteroids(BRs)strongly enhance tillering by prom oting bud outgrow th in rice,which is largely different from the function of BRs in Arabidopsis.Genetic and biochem ical analyses indicated that both the SL and BR signaling pathw ays control rice tillering by regulating the stability of D53 and/or the OsBZR1 RLA1-DLT module,a transcriptional complex in the rice BR signaling pathway.We further found that D53 interacts with OsBZR1 to inhibit the expression of FC1,a local inhibitor of tillering,and that this inhibition depends on direct DNA binding by OsBZR1,which recruits D53 to the FC1 promoter in rice buds.Taken together,these findings uncover a mechanism illustrating how SLs and BRs coordinately regulate rice tillering via the early responsive gene FC1.
基金grants from the Chinese Ministry of Science and Technology(2016YFD0100901)the Ministry of Agriculture of China(2016ZX08011001)+2 种基金the CAS President’s International Fellowship Initiative(2018VBA0025)the Youth Innovation Promotion Association CAS(2019099)the Strategic Priority Research Program of CAS(XDB27010100)(Beltran et al.,2015).
文摘Rice tillering is an important agronomic trait affecting grain yield.Here,we identified a high-tillering mutant tillering20(t20),which could be restored to the wild type by treatment with the strigolactone(SL)analog rac-GR24.T20 encodes a chloroplast ζ-carotene isomerase(Z-ISO),which is involved in the biosynthesis of ca-rotenoids and their metabolites,SL and abscisic acid(ABA).The t20 mutant has reduced SL and ABA,raising the question of how SL and ABA biosynthesis is coordinated,and whether they have overlapping functions in tillering.We discovered that rac-GR24 stimulated T20 expression and enhanced all-trans-p-carotene biosynthesis.Importantly,rac-GR24 also stimulated expression of Oryza sativa 9-CIS-EPOXY-CAROTENOID DIOXYGENASE 1(OsNCED1)through induction of Oryza sativa HOMEOBOX12(0sHOX12),promoting ABA biosynthesis in shoot base.On the other hand,ABA treatment significantly repressed SL biosynthesis and the ABA biosynthetic mutants displayed elevated SL biosynthesis.ABA treatment reduced the number of basal tillers in both t20 and wild-type plants.Furthermore,while ABA-deficient mu-tants aba1 and aba2 had the same number of basal tillers as wild type,they had more unproductive upper tillers at maturity.This work demonstrates complex interactions in the biosynthesis of carotenoid,SLs and ABA,and reveals a role for ABA in the regulation of rice tillering.
基金supported by the grant from the National Natural ScienceFoundation of China(31301250)the Talent Project from Guizhou Education Department(Qian jiao he KY zi(2021)024)+2 种基金the Wuhan Science and Technology Project(2020020601012259)the Key Cultivation Project of Guizhou University(201903)the Talent Project from Thousands of Innovative and Entrepreneurial in Guizhou Province。
文摘Multiple genes and microRNAs(miRNAs)improve grain yield by promoting tillering.MiR319s are known to regulate several aspects of plant development;however,whether miR319s are essential for tillering regulation remains unclear.Here,we report that miR319 is highly expressed in the basal part of rice plant at different development stages.The miR319 knockdown line Short Tandem Target Mimic 319(STTM319)showed higher tiller bud length in seedlings under low nitrogen(N)condition and higher tiller bud number under high N condition compared with the miR319a-overexpression line.Through targets prediction,we identified OsTCP21 and OsGAmyb as downstream targets of miR319.Moreover,OsTCP21 and OsGAmyb overexpression lines and STTM319 had increased tiller bud length and biomass,whereas both were decreased in OsTCP21 and OsGAmyb knockout lines and OE319a.These data suggest that miR319 regulates rice tiller bud development and tillering through targeting OsTCP21 and OsGAmyb.Notably,the tiller number and grain yield increased in STTM319 and overexpression lines of OsTCP21 and OsGAmyb but decreased in OE319a and knockout lines of OsTCP21 and OsGAmyb.Taken together,our findings indicate that miR319s negatively affect tiller number and grain yield by targeting OsTCP21 and OsGAmyb,revealing a novel function for miR319 in rice.
基金This work was supported by grants from National Natural Science Foundation of China(grant no.31788103)to J.L.and Y.Q.and the National Key R&D Program of China(grant no.2016YFA0500800)to Y.Q.Y.Q.is a visiting investigator of the CAS Center for Excellence in Molecular Plant Sciences.
文摘Tillering is a major determinant of rice plant architecture and grain yield.Here,we report that depletion of rice OsNRPD1a and OsNRPD1b,two orthologs of the largest subunit of RNA polymerase IV,leads to a high-tillering phenotype,in addition to dwarfism and smaller panicles.OsNRPD1a and OsNRPD1b are required for the production of 24-nt small interfering RNAs that direct DNA methylation at transposable elements(TEs)including miniature inverted-repeat TEs(MITEs).Interestingly,many genes are regulated either positively or negatively by TE methylation.Among them,OsMIR156d and OsMIR156j,which promote rice tillering,are repressed by CHH methylation at two MITEs in the promoters.By contrast,D14,which suppresses rice tillering,is activated by CHH methylation at an MITE in its downstream.Our findings reveal regulation of rice tillering by RNA-directed DNA methylation at MITEs and provide potential targets for agronomic trait enhancement through epigenome editing.
基金supported by the National Transgenic Major Program of China (Grant Nos. 2008ZX003-002 and 2009ZX08009-093B)the National High-Tech Research and Development Program of China (Grant No.2008AA10Z158-2)+1 种基金the National Natural Science Foundation of China (Grant Nos. 30971555 and 30671124)and the State Key Laboratory for Agrobiotechnology in China (Grant No. 2010SKLAB05-12)
文摘Plant architecture determines grain production in rice(Oryza sativa) and is affected by important agronomic traits such as tillering,plant height,and panicle morphology.Many key genes involved in controlling the initiation and outgrowth of axillary buds,the elongation of stems,and the architecture of inflorescences have been isolated and analyzed.Previous studies have shown that SiPf40,which was identified from a foxtail millet(Setaria italica) immature seed cDNA library,causes extra branches and tillers in SiPf40-transgenic tobacco and foxtail millet,respectively.To reconfirm its function,we generated transgenic rice plants overexpressing SiPf40 under the control of the ubiquitin promoter.SiPf40-overexpressing transgenic plants have a greater tillering number and a wider tiller angle than wild-type plants.Their root architecture is modified by the promotion of lateral root development,and the distribution of xylem and phloem in the vascular bundle is affected.Analysis of hormone levels showed that the ratios of indole-3-acetic acid/zeatin(IAA/ZR) and IAA/gibberellic acid(IAA/GA) decreased in SiPf40-transgenic plants compared with wild-type plants.These findings strongly suggest that SiPf40 plays an important role in plant architecture.
基金This work was supported by the National Natural Science Foundation of China (Grant No. 30170079)the State Key Basic Development Plan Programm (Grant No. G1998010100).
文摘The emission of microwave sulfur lamp is mainly composed of visible light. The sulfur lamp, producing little infrared radiation, has high efficiency, long duration of illumination and less energy consumption. In order to probe the agricultural application of the lamp, experiments were carried out with wheat (cv. Yangmai 158) to emphatically study illuminating effects of xenon or sulfur lamp on tillering, jointing and net photosynthetic rate during tillering and jointing periods. Results indicated that there is almost no difference in net photosynthetic rate of wheat leaves growing under different lamps. Xenon lamp significantly advanced the time of jointing, decreased number of tillers, number of total leaves per plant and leaf size, as well as inhibited root growth. In contrast with xenon lamp, sulfur lamp evidently delays the time of heading and grain maturation, increased number of heads per plant, head length, total number of grains per plant, head weight and total grain weight per plant,
基金supported by the National Natural Science Foundation of China(32260498)the Guizhou Provincial Science and Technology Project(qiankehejichu-ZK(2022)Key 008)+2 种基金the Wuhan Science and Technology Project(2020020601012259)the Guizhou Provincial Science and Technology Support Plan(qiankehezhicheng(2022)Key 026)the Key Cultivation Project of Guizhou University(201903)。
文摘Nitrogen(N)fertilization is necessary for obtaining high rice yield.But excessive N fertilizer reduces rice plant N efficiency and causes negative effects such as environmental pollution.In this study,we assembled key genes involved in different nodes of N pathways to boost nitrate and ammonium uptake and assimilation,and to strengthen amino acid utilization to increase grain yield and nitrogen use efficiency(NUE)in rice.The combinations OsNPF8.9a×OsNR2,OsAMT1;2×OsGS1;2×OsAS1,and OsGS2×OsAS2×OsANT3 optimized nitrate assimilation,ammonium conversion,and N reutilization,respectively.In co-overexpressing rice lines obtained by co-transformation,the tiller number,biomass,and grain yield per plant of the OsAMT1;2×OsGS1;2×OsAS1-overexpressing line exceeded those of wild-type ZH11,the OsNPF8.9a×OsNR2×OsGS1;2×OsAS1-overexpressing line,and the OsGS2×OsAS2×OsANT3-overexpressing line.The glutamine synthase activity,free amino acids,and nitrogen utilization efficiency(NUt E)of the OsAMT1;2×OsGS1;2×OsAS1-overexpressing line exceeded those of ZH11 and other lines that combined key genes.N influx efficiency was increased in the OsAMT1;2×OsGS1;2×OsAS1-overexpressing line and OsNPF8.9a×OsNR2×OsGS1;2×OsAS1-overexpressing line under a low ammonium and a low nitrate treatment,respectively.We propose that combining overexpression of OsAMT1;2,OsGS1;2,and OsAS1 is a promising breeding strategy for systematically increasing rice grain yield and NUE by focusing on key nodes in the N pathway.
基金supported by the National Natural Science Foundation of China(31771711 and 32071953)the National Key Research and Development Program of China(2016YFD0300405)+1 种基金the Priority Academic Program Development of Jiangsu Higher Education Institutions,China,the Project of the Vice General Manager of Science and Technology of Jiangsu Province,China(FZ20211472)the Plan of Gathering 1000 Leading Talents of Suqian,China.
文摘Genetic improvement has promoted wheat’s grain yield and nitrogen use efficiency(NUE)during the past decades.Therefore,the current wheat cultivars exhibit higher grain yield and NUE than previous cultivars in the Yangtze River Basin,China since the 2000s.However,the critical traits and mechanisms of the increased grain yield and NUE remain unknown.This study explores the mechanisms underlying these new cultivars’increased grain yield and NUE by studying 21 local cultivars cultivated for three growing seasons from 2016 to 2019.Significantly positive correlations were observed between grain yield and NUE in the three years.The cultivars were grouped into high(HH),medium(MM),and low(LL)grain yield and NUE groups.The HH group exhibited significantly high grain yield and NUE.High grain yield was attributed to more effective ears by high tiller fertility and greater single-spike yield by increasing post-anthesis single-stem biomass.Compared to other groups,the HH group demonstrated a longer leaf stay-green ability and a greater flag leaf photosynthetic rate after anthesis.It also showed higher N accumulation at pre-anthesis,which contributed to increasing N accumulation per stem,including stem and leaf sheath,leaf blade,and unit leaf area at pre-anthesis,and promoting N uptake efficiency,the main contribution of high NUE.Moreover,tiller fertility was positively related to N accumulation per stem,N accumulation per unit leaf area,leaf stay-green ability,and flag leaf photosynthetic rate,which indicates that improving tiller fertility promoted N uptake,leaf N accumulation,and photosynthetic ability,thereby achieving synchronous improvements in grain yield and NUE.Therefore,tiller fertility is proposed as an important kernel indicator that can be used in the breeding and management of cultivars to improve agricultural efficiency and sustainability.
