The yield and nitrogen use efficiency(NUE)of hybrid rice combinations are closely related to restorer line.Therefore,it is essential to evaluate the agronomic characteristics of restorer lines with high yield and high...The yield and nitrogen use efficiency(NUE)of hybrid rice combinations are closely related to restorer line.Therefore,it is essential to evaluate the agronomic characteristics of restorer lines with high yield and high NUE(HYHN).However,it is unclear which restorer lines are HYHN,and neither have the common agronomic traits of the HYHN restorer lines been identified.Aiming to address this issue,we conducted two filed experiments using three nitrogen applications,which screened five HYHN restorer lines from 15 indica restorer lines.Yield,NUE and nutrient transportation of restorer lines with different yields and NUE types were examined.Yield and total nitrogen absorption in aboveground biomass(TNA)increased,whereas NUE for grain production decreased with increasing nitrogen application levels.The HYHN restorer lines had large spikelets and high weight per panicle that were significantly positively correlated with yield and NUE.Therefore,large sink potential may be beneficial for both yield and NUE.We further studied the differences in nutrient transportation to panicles between the HYHN and low yield and low NUE(LYLN)restorer lines and found that the former had a higher nitrogen absorption level and dry matter weight ratios of panicle in maturity.Moreover,the HYHN lines also had a higher root and neck-panicle node bleeding intensity per stem after heading and more developed vascular bundles of neck-panicle nodes and leaves than the LYLN lines,which could contribute to the transportation of nutrients from root to ground and from stem and leaf to spike.Therefore,the advantages of large sink potential of the HYHN restorer lines include large nutrient accumulation in and distribution to the panicles and smooth flow of nutrients along the transportation channels.展开更多
The indispensable role of nitrogen fertilizer in ensuring world food security together with the severe threats it poses to the ecosystem makes the usage of nitrogen fertilizer a major challenge for sustainable agricul...The indispensable role of nitrogen fertilizer in ensuring world food security together with the severe threats it poses to the ecosystem makes the usage of nitrogen fertilizer a major challenge for sustainable agriculture.Genetic improvement of crops with high nitrogen-use efficiency(NUE)is one of the most feasible solutions for tackling this challenge.In the last two decades,extensive efforts toward dissecting the variation of NUE-related traits and the underlying genetic basis in different germplasms have been made,and a series of achievements have been obtained in crops,especially in rice.Here,we summarize the approaches used for genetic dissection of NUE and the functions of the causal genes in modulating NUE as well as their applications in NUE improvement in rice.Strategies for exploring the variants controlling NUE and breeding future crops with“less-input-more-output”for sustainable agriculture are also proposed.展开更多
Biological nitrification inhibitors(BNIs)are released from plant roots and inhibit the nitrification activity of microorganisms in soils,reducing NO_(3)^(‒)leaching and N2O emissions,and increasing nitrogenuse efficie...Biological nitrification inhibitors(BNIs)are released from plant roots and inhibit the nitrification activity of microorganisms in soils,reducing NO_(3)^(‒)leaching and N2O emissions,and increasing nitrogenuse efficiency(NUE).Several recent studies have focused on the identification of new BNIs,yet little is known about the genetic loci that govern their biosynthesis and secretion.We applied a combined transcriptomic and metabolomic analysis to investigate possible biosynthetic pathways and transporters involved in the biosynthesis and release of BNI 1,9-decanediol(1,9-D),which was previously identified in rice root exudates.Our results linked four fatty acids,icosapentaenoic acid,linoleate,norlinolenic acid,and polyhydroxy-α,ω-divarboxylic acid,with 1,9-D biosynthesis and three transporter families,namely the ATP-binding cassette protein family,the multidrug and toxic compound extrusion family,and the major facilitator superfamily,with 1,9-D release from roots into the soil medium.Our finding provided candidates for further work on the genes implicated in the biosynthesis and secretion of 1,9-D and pinpoint genetic loci for crop breeding to improve NUE by enhancing 1,9-D secretion,with the potential to reduce NO_(3)^(‒)leaching and N2O emissions from agricultural soils.展开更多
We conducted field trials of rice grown in sandy soil and clay soil to determine the effects of nitrogen application levels on the concentration of NH4＋-N in surface water, loss of ammonia through volatilization from...We conducted field trials of rice grown in sandy soil and clay soil to determine the effects of nitrogen application levels on the concentration of NH4＋-N in surface water, loss of ammonia through volatilization from paddy fields, rice production, nitrogen-use efficiency, and nitrogen content in the soil profile. The concentration of NH4＋-N in surface water and the amount of ammonia lost through volatilization increased with increasing nitrogen application level, and peaked at 1-3 d after nitrogen application. Less ammonia was lost via volatilization from clay soil than from sandy soil. The amounts of ammonia lost via volatilization after nitrogen application differed depending on the stage when it was applied, from the highest loss to the lowest： N application to promote tillering 〉 the first N topdressing to promote panicle initiation （applied at the last 4-leaf stage） 〉 basal fertilizer 〉 the second N topdressing to promote panicle initiation （applied at the last 2-leaf stage）. The total loss of ammonia via volatilization from clay soil was 10.49-87.06 kg/hm2, equivalent to 10.92%-21.76% of the nitrogen applied. The total loss of ammonia via volatilization from sandy soil was 11.32-102.43 kg/hm2, equivalent to 11.32%-25.61 % of the nitrogen applied. The amount of ammonia lost via volatilization and the concentration of NH4＋-N in surface water peaked simultaneously after nitrogen application; both showed maxima at the tillering stage with the ratio between them ranging from 23.76% to 33.65%. With the increase in nitrogen application level, rice production and nitrogen accumulation in plants increased, but nitrogen-use efficiency decreased. Rice production and nitrogen accumulation in plants were slightly higher in clay soil than in sandy soil. In the soil, the nitrogen content was the lowest at a depth of 40-50 cm. In any specific soil layer, the soil nitrogen content increased with increasing nitrogen application level, and the soil nitrogen content was higher in clay soil than in sandy soil. In terms of ammonia volatilization, the amount of ammonia lost via volatilization increased markedly when the nitrogen application level exceeded 250 kg/hm2 in the rice growing season. However, for rice production, a suitable nitrogen application level is approximately 300 kg/hm2. Therefore, taking the needs for high crop yields and environmental protection into account, the appropriate nitrogen application level was 250-300 kg/hm2 in these conditions.展开更多
Sesame is mainly cultivated under traditional,low-input agro-systems.Recent breeding developments promoted the modernization and mechanization of sesame cultivation.However,only a few articles have been published conc...Sesame is mainly cultivated under traditional,low-input agro-systems.Recent breeding developments promoted the modernization and mechanization of sesame cultivation.However,only a few articles have been published concerning fertilization requirements for both modern and traditional agro-systems.In field trials at two locations,we determined the response of irrigated sesame to nitrogen(N).Three promising sesame lines were tested combining two irrigation levels with four N levels.At a high irrigation level,N had a significant effect on growth,branching,and consequently,seed yield exceeding two-ton ha^(-1).A high N doze was accompanied by a decrease in the photosynthetic rate and leaf water potential.The δ^(13)C confirmed lower stomatal conductance under high N treatments.Under deficit irrigation,the N level had a minor effect on the monitored parameters,indicating N fertilization was not efficient.Seed oil content was negatively correlated with seed N concentration.Our results question the necessity of N application when water is limited,as N fertilization promotes vigorous development that rapidly depletes soil water.Thus,water availability should be considered when developing an N management strategy.For high-yielding agro-systems,roughly 80–120 kg ha^(-1)N is required for optimal yield,bearing in mind the negative association between seed-N and oil content.展开更多
Leaf nitrogen resorption is very important to Phyllostachys edulis development because the withdrawn nitrogen can help newly emerging and growing culms.However, few studies have focused on the ontogenetic changes in l...Leaf nitrogen resorption is very important to Phyllostachys edulis development because the withdrawn nitrogen can help newly emerging and growing culms.However, few studies have focused on the ontogenetic changes in leaf nitrogen resorption of P. edulis. Here, we examined the variability in mature leaf nitrogen concentrations(Nm), nitrogen resorption efficiency(NRE) and proficiency(NRP or Ns) and leaf-level nitrogen use efficiency(NUE) of the current-, 3 rd-and 5 th-year culms in P.edulis stands under extensive management. Analyses of variance and correlation indicated that patterns of Nm,NRP, NRE and NUE were markedly affected by culm age and leaf nitrogen status. Nm, Nsand NRE were significant higher in younger(current-year) culms with 1-year lifespan leaves, while NUE was markedly higher in older(3 rd-or 5 th-year) culms with 2-year lifespan leaves. Significant linear correlations between Nmand NRP, NRE and NUE,Nmand NUE, Nsand NRE were found for each culm age,and Nmwas significantly positively correlated to NRE for all culms pooled. Higher proficiency in older culms led to higher NUE and lower NRE, these relationships can be modulated by Nm, which in turn, is restrained by leaf N availability and acquisition. Our results revealed that at the intraspecific level, P. edulis can adjust its leaf NRE, NRP,and leaf-level NUE in concert with culm development.Understanding nitrogen resorption characteristics and NUE of P. edulis can help decision-makers design appropriate deforestation strategies and achieve precise N fertilization for sustainable bamboo forest management.展开更多
Modern semi-dwarf rice varieties of the“Green Revolution”require a high supply of nitrogen(N)fertilizer to produce high yields.A better understanding of the interplay between N metabolism and plant developmental pro...Modern semi-dwarf rice varieties of the“Green Revolution”require a high supply of nitrogen(N)fertilizer to produce high yields.A better understanding of the interplay between N metabolism and plant developmental processes is required for improved N-use efficiency and agricultural sustainability.Here,we show that strigolactones(SLs)modulate root metabolic and developmental adaptations to low N availability for ensuring efficient uptake and translocation of available N.The key repressor DWARF 53(D53)of the SL signaling pathway interacts with the transcription factor GROWTH-REGULATING FACTOR 4(GRF4)and prevents GRF4 from binding to its target gene promoters.N limitation induces the accumulation of SLs,which in turn promotes SL-mediated degradation of D53,leading to the release of GRF4 and thus promoting the expression of genes associated with N metabolism.N limitation also induces degradation of the DELLA protein SLENDER RICE 1(SLR1)in an D14-and D53-dependent manner,effectively releasing GRF4 from competitive inhibition caused by SLR1.Collectively,our findings reveal a previously unrecognized mechanism underlying SL and gibberellin crosstalk in response to N availability,advancing our understanding of plant growth–metabolic coordination and facilitating the design of the strategies for improving N-use efficiency in high-yield crops.展开更多
The Green Revolution of the 1960s boosted crop yields in part through widespread production of semidwarf plant cultivars and extensive use of mineral fertilizers.The beneficial semidwarfism of cereal Green Revolution ...The Green Revolution of the 1960s boosted crop yields in part through widespread production of semidwarf plant cultivars and extensive use of mineral fertilizers.The beneficial semidwarfism of cereal Green Revolution cultivars is due to the accumulation of plant growth-repressing DELLA proteins,which increases lodging resistance but requires a high-nitrogen fertilizer to obtain high yield.Given that environmentally degrading fertilizer use underpins current worldwide crop production,future agricultural sustainability needs a sustainable Green Revolution through reducing N fertilizer use while boosting grain yield above what is currently achievable.Despite a great deal of research efforts,only a few genes have been demonstrated to improve N-use efficiency in crops.The molecular mechanisms underlying the coordination between plant growth and N metabolism is still not fully understood,thus preventing significant improvement.Recent advances of how plants sense,capture and respond to varying N supply in model plants have shed light on how to improve sustainable productivity in agriculture.This review focuses on the current understanding of root developmental and metabolic adaptations to N availability,and discuss the potential approaches to improve N-use efficiency in high-yielding cereal crops.展开更多
Agriculture is facing a massive increase in demand per hectare as a result of an ever-expanding population and environmental deterioration.While we have learned much about how environmental conditions and diseases imp...Agriculture is facing a massive increase in demand per hectare as a result of an ever-expanding population and environmental deterioration.While we have learned much about how environmental conditions and diseases impact crop yield,until recently considerably less was known concerning endogenous factors,including within-plant nutrient allocation.In this review,we discuss studies of source-sink interactions covering both fundamental research in model systems under controlled growth conditions and how the findings are being translated to crop plants in the field.In this respect we detail efforts aimed at improving and/or combining C3,C4,and CAM modes of photosynthesis,altering the chloroplastic electron transport chain,modulating photorespiration,adopting bacterial/algal carbon-concentrating mechanisms,and enhancing nitrogen-and water-use efficiencies.Moreover,we discuss how modulating TCA cycle activities and primary metabolism can result in increased rates of photosynthesis and outline the opportunities that evaluating natural variation in photosynthesis may afford.Although source,transport,and sink functions are all covered in this review,we focus on discussing source functions because the majority of research has been conducted in this field.Nevertheless,considerable recent evidence,alongside the evidence from classical studies,demonstrates that both transport and sink functions are also incredibly important determinants of yield.We thus describe recent evidence supporting this notion and suggest that future strategies for yield improvement should focus on combining improvements in each of these steps to approach yield optimization.展开更多
Aims Competition among plants in a community usually depends on their nitrogen(N)-use efficiency(NUE)and water-use efficiency(WUE)in arid and semi-arid regions.Artemisia frigida is an indicator species in heavily degr...Aims Competition among plants in a community usually depends on their nitrogen(N)-use efficiency(NUE)and water-use efficiency(WUE)in arid and semi-arid regions.Artemisia frigida is an indicator species in heavily degraded grassland,however,how its NUE and WUE respond to N addition in different successional stages is still unclear,especially with mowing,a common management practice in semi-arid grasslands.Methods Based on a long-term controlled experiment with N addition and mowing in an abandoned cropland from 2006 to 2013,we investigated the NUE and WUE oi A.frigida in two patches(i.e.grass and herb patches)in 2013 which represented two potential successional stages from herb to grass communities.The coverage of A.frigida was higher(about 50%)in the herb patch than in the grass patch(about 10%).Stable isotopic C(δ^(13)C)and N(δ^(15)N)as well as C and N pools were measured in plants and soils.NUE was calculated as leaf C/N,and leafδ^(13)C values were used as a proxy for WUE.Important Findings N addition did not affect WUE of A.frigida,but significantly decreased NUE by 42.9%and 26.6%in grass and herb patches,respectively.The response of NUE to N addition was related to altering utilization of different N sources(NH_(4)^(+)vs.NO_(3)^(-))by A.frigida according to the changed relationship between leafδ^(15)N/soil 615N and NUE.Mowing had no effect on NUE regardless of N addition,but significantly increased WUE by 2.3%for A.frigida without N addition in the grass patch.The addition of N reduced the positive effect of mowing on its WUE in grass patch.Our results suggested that decreased NUE and/or WUE of A.frigida under mowing and N addition could reduce its competition,and further accelerate restoration succession from the abandoned cropland to natural grassland in the semi-arid region.展开更多
The agricultural Green Revolution gave rise to semi-dwarf varieties that increased wheat and rice yields under nitrogen-intensive and high-density planting conditions.However,maize,a cornerstone of global food securit...The agricultural Green Revolution gave rise to semi-dwarf varieties that increased wheat and rice yields under nitrogen-intensive and high-density planting conditions.However,maize,a cornerstone of global food security,has not undergone equivalent architectural improvement.During the 1940s-1960s,signifi-cant yield gains in maize were achieved via hybrid breeding.Nevertheless,the growing demand for high-density planting has exposed challenges for maize,such as lodging susceptibility and nutrient competition,driving an urgent need for shorter hybrid maize varieties.Here,we summarize recent advances in maize height regulation,architectural optimization,and nitrogen-use efficiency,which provide actionable targets for semi-dwarf maize breeding.Recent biotechnology breakthroughs now enable the development of semi-dwarf maize varieties with enhanced lodging resistance and reduced fertilizer dependency,thereby over-coming the historical limitations of Green Revolution varieties.We propose that semi-dwarf maize holds the potential to revolutionize maize production by enhancing resilience,yield,and sustainability.展开更多
基金the National Natural Science Foundation of China(31871564)the National Key R&D Program of China(2016YFD0300506 and 2017YFD0301700)the Sichuan Breeding Key Research Project,China(2016NYZ0051)。
文摘The yield and nitrogen use efficiency(NUE)of hybrid rice combinations are closely related to restorer line.Therefore,it is essential to evaluate the agronomic characteristics of restorer lines with high yield and high NUE(HYHN).However,it is unclear which restorer lines are HYHN,and neither have the common agronomic traits of the HYHN restorer lines been identified.Aiming to address this issue,we conducted two filed experiments using three nitrogen applications,which screened five HYHN restorer lines from 15 indica restorer lines.Yield,NUE and nutrient transportation of restorer lines with different yields and NUE types were examined.Yield and total nitrogen absorption in aboveground biomass(TNA)increased,whereas NUE for grain production decreased with increasing nitrogen application levels.The HYHN restorer lines had large spikelets and high weight per panicle that were significantly positively correlated with yield and NUE.Therefore,large sink potential may be beneficial for both yield and NUE.We further studied the differences in nutrient transportation to panicles between the HYHN and low yield and low NUE(LYLN)restorer lines and found that the former had a higher nitrogen absorption level and dry matter weight ratios of panicle in maturity.Moreover,the HYHN lines also had a higher root and neck-panicle node bleeding intensity per stem after heading and more developed vascular bundles of neck-panicle nodes and leaves than the LYLN lines,which could contribute to the transportation of nutrients from root to ground and from stem and leaf to spike.Therefore,the advantages of large sink potential of the HYHN restorer lines include large nutrient accumulation in and distribution to the panicles and smooth flow of nutrients along the transportation channels.
基金National Key Research and Development Program of China(2021YFF1000400)National Nat-ural Science Foundation of China(31922007).
文摘The indispensable role of nitrogen fertilizer in ensuring world food security together with the severe threats it poses to the ecosystem makes the usage of nitrogen fertilizer a major challenge for sustainable agriculture.Genetic improvement of crops with high nitrogen-use efficiency(NUE)is one of the most feasible solutions for tackling this challenge.In the last two decades,extensive efforts toward dissecting the variation of NUE-related traits and the underlying genetic basis in different germplasms have been made,and a series of achievements have been obtained in crops,especially in rice.Here,we summarize the approaches used for genetic dissection of NUE and the functions of the causal genes in modulating NUE as well as their applications in NUE improvement in rice.Strategies for exploring the variants controlling NUE and breeding future crops with“less-input-more-output”for sustainable agriculture are also proposed.
基金supported by the National Natural Science Foundation of China(Grant Nos.32030099 and 32072670)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA28020301)+1 种基金the Youth Innovation Promotion Association of the Chinese Academy of Sciences(Grant No.2023326)the Enterprise Cooperation Projects of China(Grant No.Am20210407RD).
文摘Biological nitrification inhibitors(BNIs)are released from plant roots and inhibit the nitrification activity of microorganisms in soils,reducing NO_(3)^(‒)leaching and N2O emissions,and increasing nitrogenuse efficiency(NUE).Several recent studies have focused on the identification of new BNIs,yet little is known about the genetic loci that govern their biosynthesis and secretion.We applied a combined transcriptomic and metabolomic analysis to investigate possible biosynthetic pathways and transporters involved in the biosynthesis and release of BNI 1,9-decanediol(1,9-D),which was previously identified in rice root exudates.Our results linked four fatty acids,icosapentaenoic acid,linoleate,norlinolenic acid,and polyhydroxy-α,ω-divarboxylic acid,with 1,9-D biosynthesis and three transporter families,namely the ATP-binding cassette protein family,the multidrug and toxic compound extrusion family,and the major facilitator superfamily,with 1,9-D release from roots into the soil medium.Our finding provided candidates for further work on the genes implicated in the biosynthesis and secretion of 1,9-D and pinpoint genetic loci for crop breeding to improve NUE by enhancing 1,9-D secretion,with the potential to reduce NO_(3)^(‒)leaching and N2O emissions from agricultural soils.
基金supported by the National Natural Science Foundation of China (Grant No.30671223)the 11th 5-year Major Project of National Science and Technology Support Plan (GrantNo. 2006BAD02A03)
文摘We conducted field trials of rice grown in sandy soil and clay soil to determine the effects of nitrogen application levels on the concentration of NH4＋-N in surface water, loss of ammonia through volatilization from paddy fields, rice production, nitrogen-use efficiency, and nitrogen content in the soil profile. The concentration of NH4＋-N in surface water and the amount of ammonia lost through volatilization increased with increasing nitrogen application level, and peaked at 1-3 d after nitrogen application. Less ammonia was lost via volatilization from clay soil than from sandy soil. The amounts of ammonia lost via volatilization after nitrogen application differed depending on the stage when it was applied, from the highest loss to the lowest： N application to promote tillering 〉 the first N topdressing to promote panicle initiation （applied at the last 4-leaf stage） 〉 basal fertilizer 〉 the second N topdressing to promote panicle initiation （applied at the last 2-leaf stage）. The total loss of ammonia via volatilization from clay soil was 10.49-87.06 kg/hm2, equivalent to 10.92%-21.76% of the nitrogen applied. The total loss of ammonia via volatilization from sandy soil was 11.32-102.43 kg/hm2, equivalent to 11.32%-25.61 % of the nitrogen applied. The amount of ammonia lost via volatilization and the concentration of NH4＋-N in surface water peaked simultaneously after nitrogen application; both showed maxima at the tillering stage with the ratio between them ranging from 23.76% to 33.65%. With the increase in nitrogen application level, rice production and nitrogen accumulation in plants increased, but nitrogen-use efficiency decreased. Rice production and nitrogen accumulation in plants were slightly higher in clay soil than in sandy soil. In the soil, the nitrogen content was the lowest at a depth of 40-50 cm. In any specific soil layer, the soil nitrogen content increased with increasing nitrogen application level, and the soil nitrogen content was higher in clay soil than in sandy soil. In terms of ammonia volatilization, the amount of ammonia lost via volatilization increased markedly when the nitrogen application level exceeded 250 kg/hm2 in the rice growing season. However, for rice production, a suitable nitrogen application level is approximately 300 kg/hm2. Therefore, taking the needs for high crop yields and environmental protection into account, the appropriate nitrogen application level was 250-300 kg/hm2 in these conditions.
基金supported by the CFPN fund (Center of Fertilization and Plant Nutrition, grant number ICLF20161)。
文摘Sesame is mainly cultivated under traditional,low-input agro-systems.Recent breeding developments promoted the modernization and mechanization of sesame cultivation.However,only a few articles have been published concerning fertilization requirements for both modern and traditional agro-systems.In field trials at two locations,we determined the response of irrigated sesame to nitrogen(N).Three promising sesame lines were tested combining two irrigation levels with four N levels.At a high irrigation level,N had a significant effect on growth,branching,and consequently,seed yield exceeding two-ton ha^(-1).A high N doze was accompanied by a decrease in the photosynthetic rate and leaf water potential.The δ^(13)C confirmed lower stomatal conductance under high N treatments.Under deficit irrigation,the N level had a minor effect on the monitored parameters,indicating N fertilization was not efficient.Seed oil content was negatively correlated with seed N concentration.Our results question the necessity of N application when water is limited,as N fertilization promotes vigorous development that rapidly depletes soil water.Thus,water availability should be considered when developing an N management strategy.For high-yielding agro-systems,roughly 80–120 kg ha^(-1)N is required for optimal yield,bearing in mind the negative association between seed-N and oil content.
基金supported by the Key Project of National Key Research and Development Plans(2016YFC0500204)the Chinese National Basic Research Program(2013BAC03B05)+1 种基金the Key Project for the Strategic Science Plan in Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences(No.2012ZD007)State Forestry Administration project948(2014-4-58)
文摘Leaf nitrogen resorption is very important to Phyllostachys edulis development because the withdrawn nitrogen can help newly emerging and growing culms.However, few studies have focused on the ontogenetic changes in leaf nitrogen resorption of P. edulis. Here, we examined the variability in mature leaf nitrogen concentrations(Nm), nitrogen resorption efficiency(NRE) and proficiency(NRP or Ns) and leaf-level nitrogen use efficiency(NUE) of the current-, 3 rd-and 5 th-year culms in P.edulis stands under extensive management. Analyses of variance and correlation indicated that patterns of Nm,NRP, NRE and NUE were markedly affected by culm age and leaf nitrogen status. Nm, Nsand NRE were significant higher in younger(current-year) culms with 1-year lifespan leaves, while NUE was markedly higher in older(3 rd-or 5 th-year) culms with 2-year lifespan leaves. Significant linear correlations between Nmand NRP, NRE and NUE,Nmand NUE, Nsand NRE were found for each culm age,and Nmwas significantly positively correlated to NRE for all culms pooled. Higher proficiency in older culms led to higher NUE and lower NRE, these relationships can be modulated by Nm, which in turn, is restrained by leaf N availability and acquisition. Our results revealed that at the intraspecific level, P. edulis can adjust its leaf NRE, NRP,and leaf-level NUE in concert with culm development.Understanding nitrogen resorption characteristics and NUE of P. edulis can help decision-makers design appropriate deforestation strategies and achieve precise N fertilization for sustainable bamboo forest management.
基金supported by the National Natural Science Foundation of China(grant nos.31830082,31972501,31672225,and 31601821)the National Key R&D Programme of China(2022YFD1200010-02 and 2022YFD1900702).
文摘Modern semi-dwarf rice varieties of the“Green Revolution”require a high supply of nitrogen(N)fertilizer to produce high yields.A better understanding of the interplay between N metabolism and plant developmental processes is required for improved N-use efficiency and agricultural sustainability.Here,we show that strigolactones(SLs)modulate root metabolic and developmental adaptations to low N availability for ensuring efficient uptake and translocation of available N.The key repressor DWARF 53(D53)of the SL signaling pathway interacts with the transcription factor GROWTH-REGULATING FACTOR 4(GRF4)and prevents GRF4 from binding to its target gene promoters.N limitation induces the accumulation of SLs,which in turn promotes SL-mediated degradation of D53,leading to the release of GRF4 and thus promoting the expression of genes associated with N metabolism.N limitation also induces degradation of the DELLA protein SLENDER RICE 1(SLR1)in an D14-and D53-dependent manner,effectively releasing GRF4 from competitive inhibition caused by SLR1.Collectively,our findings reveal a previously unrecognized mechanism underlying SL and gibberellin crosstalk in response to N availability,advancing our understanding of plant growth–metabolic coordination and facilitating the design of the strategies for improving N-use efficiency in high-yield crops.
基金supported by the National Natural Science Foundation of China(32020103004,32170251)the Strategic Priority Research Program of Chinese Academy of Sciences(XDA24020309+1 种基金the Youth Innovation Promotion Association CAS(2019100)Key-Area Research and Development Program of Guangdong Province(2018B020202012)。
文摘The Green Revolution of the 1960s boosted crop yields in part through widespread production of semidwarf plant cultivars and extensive use of mineral fertilizers.The beneficial semidwarfism of cereal Green Revolution cultivars is due to the accumulation of plant growth-repressing DELLA proteins,which increases lodging resistance but requires a high-nitrogen fertilizer to obtain high yield.Given that environmentally degrading fertilizer use underpins current worldwide crop production,future agricultural sustainability needs a sustainable Green Revolution through reducing N fertilizer use while boosting grain yield above what is currently achievable.Despite a great deal of research efforts,only a few genes have been demonstrated to improve N-use efficiency in crops.The molecular mechanisms underlying the coordination between plant growth and N metabolism is still not fully understood,thus preventing significant improvement.Recent advances of how plants sense,capture and respond to varying N supply in model plants have shed light on how to improve sustainable productivity in agriculture.This review focuses on the current understanding of root developmental and metabolic adaptations to N availability,and discuss the potential approaches to improve N-use efficiency in high-yielding cereal crops.
基金We thank the Bill and Melinda Gates Foundation for funding this research through grant INV-008053"Metabolic Engineering of Carbon Pathways to Enhance Yield of Root and Tuber Crops"provided to Professor Dr.Uwe Sonnewald.Dr.Ryo Yokoyama was financially supported as the postdoc-toral fellow of the Japan Society for the Promotion of Science.
文摘Agriculture is facing a massive increase in demand per hectare as a result of an ever-expanding population and environmental deterioration.While we have learned much about how environmental conditions and diseases impact crop yield,until recently considerably less was known concerning endogenous factors,including within-plant nutrient allocation.In this review,we discuss studies of source-sink interactions covering both fundamental research in model systems under controlled growth conditions and how the findings are being translated to crop plants in the field.In this respect we detail efforts aimed at improving and/or combining C3,C4,and CAM modes of photosynthesis,altering the chloroplastic electron transport chain,modulating photorespiration,adopting bacterial/algal carbon-concentrating mechanisms,and enhancing nitrogen-and water-use efficiencies.Moreover,we discuss how modulating TCA cycle activities and primary metabolism can result in increased rates of photosynthesis and outline the opportunities that evaluating natural variation in photosynthesis may afford.Although source,transport,and sink functions are all covered in this review,we focus on discussing source functions because the majority of research has been conducted in this field.Nevertheless,considerable recent evidence,alongside the evidence from classical studies,demonstrates that both transport and sink functions are also incredibly important determinants of yield.We thus describe recent evidence supporting this notion and suggest that future strategies for yield improvement should focus on combining improvements in each of these steps to approach yield optimization.
基金This work was supported by National Natural Science Foundation of China(31770526,31872406)the Chinese National Key Development Program for Basic Research(2016YFC0500703).
文摘Aims Competition among plants in a community usually depends on their nitrogen(N)-use efficiency(NUE)and water-use efficiency(WUE)in arid and semi-arid regions.Artemisia frigida is an indicator species in heavily degraded grassland,however,how its NUE and WUE respond to N addition in different successional stages is still unclear,especially with mowing,a common management practice in semi-arid grasslands.Methods Based on a long-term controlled experiment with N addition and mowing in an abandoned cropland from 2006 to 2013,we investigated the NUE and WUE oi A.frigida in two patches(i.e.grass and herb patches)in 2013 which represented two potential successional stages from herb to grass communities.The coverage of A.frigida was higher(about 50%)in the herb patch than in the grass patch(about 10%).Stable isotopic C(δ^(13)C)and N(δ^(15)N)as well as C and N pools were measured in plants and soils.NUE was calculated as leaf C/N,and leafδ^(13)C values were used as a proxy for WUE.Important Findings N addition did not affect WUE of A.frigida,but significantly decreased NUE by 42.9%and 26.6%in grass and herb patches,respectively.The response of NUE to N addition was related to altering utilization of different N sources(NH_(4)^(+)vs.NO_(3)^(-))by A.frigida according to the changed relationship between leafδ^(15)N/soil 615N and NUE.Mowing had no effect on NUE regardless of N addition,but significantly increased WUE by 2.3%for A.frigida without N addition in the grass patch.The addition of N reduced the positive effect of mowing on its WUE in grass patch.Our results suggested that decreased NUE and/or WUE of A.frigida under mowing and N addition could reduce its competition,and further accelerate restoration succession from the abandoned cropland to natural grassland in the semi-arid region.
基金supported by the Beijing Rural Revitalization Agricultural Science and Technology Project(NY2401060025)the Biological Breeding-Major Projects(2023ZD0402705)+1 种基金the Beijing Scholars Program(BSPO41)the Special Program for Science and Technology Innovation Capacity Building of the Beijing Academy of Agriculture and Forestry Sciences(KJCX20240332).
文摘The agricultural Green Revolution gave rise to semi-dwarf varieties that increased wheat and rice yields under nitrogen-intensive and high-density planting conditions.However,maize,a cornerstone of global food security,has not undergone equivalent architectural improvement.During the 1940s-1960s,signifi-cant yield gains in maize were achieved via hybrid breeding.Nevertheless,the growing demand for high-density planting has exposed challenges for maize,such as lodging susceptibility and nutrient competition,driving an urgent need for shorter hybrid maize varieties.Here,we summarize recent advances in maize height regulation,architectural optimization,and nitrogen-use efficiency,which provide actionable targets for semi-dwarf maize breeding.Recent biotechnology breakthroughs now enable the development of semi-dwarf maize varieties with enhanced lodging resistance and reduced fertilizer dependency,thereby over-coming the historical limitations of Green Revolution varieties.We propose that semi-dwarf maize holds the potential to revolutionize maize production by enhancing resilience,yield,and sustainability.
