The purpose of this study was to identify the physiological mechanism underlying the effects of high temperature and waterlogging on summer maize.The stem development and yield of the maize hybrid Denghai 605 in respo...The purpose of this study was to identify the physiological mechanism underlying the effects of high temperature and waterlogging on summer maize.The stem development and yield of the maize hybrid Denghai 605 in response to high-temperature stress,waterlogging stress,and their combination applied for six days at the third-leaf,sixth-leaf,and tasseling stages were recorded.The combined stresses reduced lignin biosynthetic enzyme activity and lignin accumulation,leading to abnormal stem development.Reduction of the area and number of vascular bundles in stems led to reduced dry matter accumulation and allocation.Decreased grain dry weight at all three stages reduced grain yield relative to a control.In summary,high temperature,waterlogging,and their combined stress impaired stem development and grain yield of summer maize.The combined stresses were more damaging than either stress alone.展开更多
Phosphorus(P)is a nonrenewable resource and a critical element for plant growth that plays an important role in improving crop yield.Excessive P fertilizer application is widespread in agricultural production,which no...Phosphorus(P)is a nonrenewable resource and a critical element for plant growth that plays an important role in improving crop yield.Excessive P fertilizer application is widespread in agricultural production,which not only wastes phosphate resources but also causes P accumulation and groundwater pollution.Here,we hypothesized that the apparent P balance of a crop system could be used as an indicator for identifying the critical P input in order to obtain a high yield with high phosphorus use efficiency(PUE).A 12-year field experiment with P fertilization rates of 0,45,90,135,180,and 225 kg P_(2)O_(5)ha^(-1)was conducted to determine the crop yield,PUE,and soil Olsen-P value response to P balance,and to optimize the P input.Annual yield stagnation occurred when the P fertilizer application exceeded a certain level,and high yield and PUE levels were achieved with annual P fertilizer application rates of 90-135 kg P_(2)O_(5)ha^(-1).A critical P balance range of 2.15-4.45 kg P ha^(-1)was recommended to achieve optimum yield with minimal environmental risk.The critical P input range estimated from the P balance was 95.7-101 kg P_(2)O_(5)ha^(-1),which improved relative yield(>90%)and PUE(90.0-94.9%).In addition,the P input-output balance helps in assessing future changes in Olsen-P values,which increased by 4.07 mg kg^(-1)of P for every 100 kg of P surplus.Overall,the P balance can be used as a critical indicator for P management in agriculture,providing a robust reference for limiting P excess and developing a more productive,efficient and environmentally friendly P fertilizer management strategy.展开更多
Planting at an optimum density and supplying adequate nitrogen(N) to achieve higher yields is a common practice in crop production, especially for maize(Zea mays L.); however, excessive N fertilizer supply in maize pr...Planting at an optimum density and supplying adequate nitrogen(N) to achieve higher yields is a common practice in crop production, especially for maize(Zea mays L.); however, excessive N fertilizer supply in maize production results in reduced N use efficiency(NUE) and severe negative impacts on the environment. This research was conducted to determine the effects of increased plant density and reduced N rate on grain yield, total N uptake, NUE, leaf area index(LAI), intercepted photosynthetically active radiation(IPAR), and resource use efficiency in maize. Field experiments were conducted using a popular maize hybrid Zhengdan 958(ZD958) under different combinations of plant densities and N rates to determine an effective approach for maize production with high yield and high resource use efficiency. Increasing plant density was clearly able to promote N absorption and LAI during the entire growth stage, which allowed high total N uptake and interception of radiation to achieve high dry matter accumulation(DMA), grain yield, NUE, and radiation use efficiency(RUE). However, with an increase in plant density, the demand of N increased along with grain yield. Increasing N rate can significantly increase the DMA, grain yield, LAI, IPAR, and RUE. However, this increase was non-linear and due to the input of too much N fertilizers, the efficiency of N use at NCK(320 kg ha^(–1)) was low. An appropriate reduction in N rate can therefore lead to higher NUE despite a slight loss in grain production. Taking into account both the need for high grain yield and resource use efficiency, a 30% reduction in N supply, and an increase in plant density of 3 plants m^(–2), compared to LD(5.25 plants m^(–2)), would lead to an optimal balance between yield and resource use efficiency.展开更多
Compared to other crops,maize production demands relatively high temperatures.However,temperatures exceeding 35℃lead to adverse effects on maize yield.High temperatures(≥35℃)are consistently experienced by summer m...Compared to other crops,maize production demands relatively high temperatures.However,temperatures exceeding 35℃lead to adverse effects on maize yield.High temperatures(≥35℃)are consistently experienced by summer maize during its reproductive growth stage in the North China Plain,which is likely to cause irreversible crop damage.This study investigated the effects of elevating temperature(ET)treatment on the yield component of summer maize,beginning at the 9th unfolding leaf stage and ending at the tasseling stage.Results demonstrated that continuous ET led to a decrease in the elongation rate and activity of silks and an elongated interval between anthesis and silking stages,and eventually decreased grain number at ear tip and reduced yield.Although continuous ET before tasseling damaged the anther structure,reduced pollen activity,delayed the start of the pollen shedding stage,and shortened the pollen shedding time,it was inferred,based on phenotypical and physiological traits,that continuous ET after the 9th unfolding leaf stage influenced ears and therefore may have more significant impacts.Overall,when maize plants were exposed to ET treatment in the ear reproductive development stage,the growth of ears and tassels was blocked,which increased the occurrence of barren ear tips and led to large yield losses.展开更多
Ridge-furrow film mulching has been proven to be an effective water-saving and yield-improving planting pattern in arid and semi-arid regions.Drought is the main factor limiting the local agricultural production in th...Ridge-furrow film mulching has been proven to be an effective water-saving and yield-improving planting pattern in arid and semi-arid regions.Drought is the main factor limiting the local agricultural production in the Loess Plateau of China.In this study,we tried to select a suitable ridge-furrow mulching system to improve this situation.A two-year field experiment of summer maize(Zea mays L.)during the growing seasons of 2017 and 2018 was conducted to systematically analyze the effects of flat planting with no film mulching(CK),ridge-furrow with ridges mulching and furrows bare(RFM),and double ridges and furrows full mulching(DRFFM)on soil temperature,soil water storage(SWS),root growth,aboveground dry matter,water use efficiency(WUE),and grain yield.Both RFM and DRFFM significantly increased soil temperature in ridges,while soil temperature in furrows for RFM and DRFFM was similar to that for CK.The largest SWS was observed in DRFFM,followed by RFM and CK,with significant differences among them.SWS was lower in ridges than in furrows for RFM.DRFFM treatment kept soil water in ridges,resulting in higher SWS in ridges than in furrows after a period of no water input.Across the two growing seasons,compared with CK,RFM increased root mass by 10.2%and 19.3%at the jointing and filling stages,respectively,and DRFFM increased root mass by 7.9%at the jointing stage but decreased root mass by 6.0%at the filling stage.Over the two growing seasons,root length at the jointing and filling stages was respectively increased by 75.4%and 58.7%in DRFFM,and 20.6%and 30.2%in RFM.Relative to the jointing stage,the increased proportions of root mass and length at the filling stage were respectively 42.8%and 94.9%in DRFFM,63.2%and 115.1%in CK,and 76.7%and 132.1%in RFM,over the two growing seasons,showing that DRFFM slowed down root growth while RFM promoted root growth at the later growth stages.DRFFM treatment increased root mass and root length in ridges and decreased them in 0-30 cm soil layer,while RFM increased them in 0-30 cm soil layer.Compared with CK,DRFFM decreased aboveground dry matter while RFM increased it.Evapotranspiration was reduced by 9.8%and 7.1%in DRFFM and RFM,respectively,across the two growing seasons.Grain yield was decreased by 14.3%in DRFFM and increased by 13.6%in RFM compared with CK over the two growing seasons.WUE in CK was non-significantly 6.8%higher than that in DRFFM and significantly 22.5%lower than that in RFM across the two growing seasons.Thus,RFM planting pattern is recommended as a viable water-saving option for summer maize in the Loess Plateau of China.展开更多
Stable yield of staple grains must be ensured to satisfy food demands for daily dietary energy requirements against the backdrop of global climate change. Summer maize, a staple crop, suffers severe yield losses due t...Stable yield of staple grains must be ensured to satisfy food demands for daily dietary energy requirements against the backdrop of global climate change. Summer maize, a staple crop, suffers severe yield losses due to extreme rainfall events, threatening food security. A randomized block experiment with four treatments: control, no water stress(CK);waterlogging for 6 days at the third leaf, sixth leaf stage,and 10 th day after tasseling, was conducted to investigate the mechanism of waterlogging-induced yield losses of summer maize. Waterlogging delayed plant growth and impaired tassel and ear differentiation,leading to high grain yield losses of Denghai 605(DH605). Waterlogging at third leaf(V3) stage reduced the photosynthesis of DH605, reducing total dry matter weight. Waterlogging at V3 stage reduced sucrose-cleaving enzymes activities in spike nodes and ears, reducing the carbon partitioned to ears(–53.1%), shanks(–46.5%), and ear nodes(–71.5%) but increasing the carbon partitioned to ear leaves(9.6%) and tassels(43.9%) in comparison with CK. The reductions in total carbon assimilate together with the reduced carbon partitioning to ears resulted in poor development of spikes(with respectively 15.2%and 20.6% reductions in total florets and fertilized florets) and lengthened the anthesis–silking interval by around 1 day, leading to high yield losses.展开更多
Compared with single agronomic practices management during grain formation, knowledge about integrated agronomic practices management on grain-filling characteristics and physiological function of endogenous hormones ...Compared with single agronomic practices management during grain formation, knowledge about integrated agronomic practices management on grain-filling characteristics and physiological function of endogenous hormones was limited. In order to clarify this issue, two field experiments, integrated agronomic practices management(IAPM), T1(local conventional cultivation practices), T2(an optimized combination of cropping systems and fertilizer treatment), T3(treatment based on high-yield studies), and T4(further optimized combination of cropping systems and fertilizer treatment), and nitrogen rate testing(NAT)(four nitrogen rates, 0, 129.0, 184.5, and 300.0 kg N ha–1) were performed with summer maize hybrid Zhengdan 958(ZD958). Results showed that with increased nitrogen rate, the endogenous hormone balance was promoted and the grain-filling characteristics were improved sufficiently to resulting in a significant increase in grain yield. However, the grain-filling characteristics deteriorated and yield was reduced with excessive nitrogen fertilization. However, IAPM could promote hormone balance and improve grain filling characteristic. The indole-3-acetic acid(IAA), zeatin riboside(ZR), and gibberellin(GA3) contents under T2 and T4 treatments were higher and the abscisic acid(ABA) content was lower, and the ZR and GA3 contents under T3 were higher than those under T1. Those resulted in the maximum grain-filling rate(Wmax) and the active grain-filling period(P) under T2, T3 and T4 were significantly increased than those under T1, and hence promoted kernel weight and grain yield. So IAPM promoted hormone balance by improving tillage model, optimizing fertilizer rate and fertilization period, appropriately increasing planting density and delaying harvest, which promoted grain filling rate and lengthened active grain-filling period, finally increased grain yield.展开更多
[Objectives] This study was conducted to verify the field application effect of slow-release nitrogen fertilizer on summer maize in Shajiang black soil area by simultaneous sowing and fertilization, and explore the ap...[Objectives] This study was conducted to verify the field application effect of slow-release nitrogen fertilizer on summer maize in Shajiang black soil area by simultaneous sowing and fertilization, and explore the application scope and nitrogen metabolism mechanism, so as to lay a foundation for fertilizer reduction and efficiency improvement. [Methods] With maize variety Beiqing 340 and sulfur-coated urea as experimental materials, five nitrogen application levels were set, namely, control (C0), slow-release nitrogen 70 kg/hm^(2) (C70), slow-release nitrogen 140 kg/hm^(2) (C140), slow-release nitrogen 210 kg/hm^(2) (C210) and slow-release nitrogen 280 kg/hm^(2) (C280). The phosphorus and potassium fertilizers were all in accordance with the unified standard. [Results] With the application rate of slow-release nitrogen increasing, the nitrogen accumulation in organs increased first and then decreased after tasseling stage of maize. In order to reduce the fertilizing amount and increase efficiency, 210 kg/hm^(2) of slow-release nitrogen fertilizer was the best fertilizing amount for summer maize in Shajiang black soil area. [Conclusions] This study provides reference for fertilizer reduction, efficiency improvement and sustainable development of summer maize in Shajiang black soil area.展开更多
Evaluating climatic suitability of crop cultivation lays a foundation for agriculture coping with climate change scientifically. Herein, we analyse changes in the climatically suitable distribution of summer maize cul...Evaluating climatic suitability of crop cultivation lays a foundation for agriculture coping with climate change scientifically. Herein, we analyse changes in the climatically suitable distribution of summer maize cultivation in China at 1.5℃(GW1.5) and 2.0℃(GW2.0) global warming in the future according to the temperature control targets set by the Paris Agreement. Compared with the reference period (1971- 2000), the summer maize cultivation climatically suitable region (CSR) in China mainly shifts eastwards, and its acreage significantly decreases at both GW1.5 and GW2.0. Despite no dramatic changes in the CSR spatial pattern, there are considerable decreases in the acreages of optimum and suitable regions (the core of the main producing region), indicating that half-a-degree more global warming is unfavourable for summer maize production in China's main producing region. When the global warming threshold increases from GW1.5 to GW2.0, the centres-of-gravity of optimum areas shift northeastward under RCP4.5 and RCP8.5, the centres-of-gravity of both suitable and less suitable areas shift northwestward, though the northward trend is more prominent for the less suitable areas, and the centre-of-gravity of unsuitable areas shifts southeastward. Generally, half-a-degree more global warming drives the cultivable areas of summer maize to shift northward in China, while the west region shows a certain potential for expansion of summer maize cultivation.展开更多
In order to explore the appropriate irrigation schedule for summer maize,a field experiment was conducted in 2013 in Lubotan of Shaanxi Province.Soil water content,soil salinity,soil hydraulic parameters,crop growth p...In order to explore the appropriate irrigation schedule for summer maize,a field experiment was conducted in 2013 in Lubotan of Shaanxi Province.Soil water content,soil salinity,soil hydraulic parameters,crop growth parameters and summer maize yield were measured in the experiment.The SWAP model was calibrated based on field experiment observation data in 2013.The SWAP model was used to simulate and optimize irrigation schedule for summer maize after calibration.The results showed that model simulation results of soil water content,soil salinity and summer maize yield agreed well with the measured values.The Root Mean Square Error(RMSE)and Mean Relative Error(MRE)were within the allowable error ranges.The RMSE values were all lower than 0.05 cm3/cm3 and the MRE values were lower than 15%in soil water content calibration.The RMSE values were all lower than 0.1 mg/cm3 and the MRE values were lower than 20%in soil salinity calibration.The RMSE and MRE values were 1299.6 kg/hm2 and 15.26%in summer maize yield calibration.The model parameters suitable for the study area were obtained in calibration.The SWAP model could be used to simulate and optimize irrigation schedule for summer maize after calibration.The SWAP model was used to simulate soil water-salt balance,summer maize yield and water use efficiency under different irrigation schedules.The model simulation results for different irrigation schedules indicated that the optimal irrigation schedules of summer maize were three times each for jointing stage(July 5),heading stage(August 5)and grain filling stage(August 30)with irrigation amount of 128 mm,128 mm and 96 mm,respectively.The optimal irrigation quota was 352.0 mm for summer maize in the study area.展开更多
The growing degree days(GDD)is an important factor for crop growth because it affects dry matter formation and crop yield.In this study,the universal logistic models were established employing GDD and the relative GDD...The growing degree days(GDD)is an important factor for crop growth because it affects dry matter formation and crop yield.In this study,the universal logistic models were established employing GDD and the relative GDD(RGDD)as the main parameters to characterize summer maize growth indices such as plant height(H),leaf area index(LAI),and dry matter accumulation(DMA).The relationships were analyzed between the growth indices,harvest index(HI),water consumption,and yield in maize.By considering China as an example,the results showed that the logistic model performed well at simulating the changes in the summer maize growth indices in different regions and the universal model parameters were within specific ranges.Furthermore,the logistic model with RGDD as the independent variable was more suitable for modeling summer maize growth in large areas than GDD.The relationship between the maximum LAI and HI was described by a quadratic polynomial function.HI was optimal(0.53)when the maximum LAI was about 5.13.The maximum LAI,maximum H,and maximum DMA could be described by a quadratic polynomial function of water consumption during the growing season.The summer maize yield could be predicted with a binary quadratic equation using the maximum GDD and water consumption.This study confirmed that a logistic model can be used to establish a universal growth model for summer maize in large areas.Reasonable ranges of parameters were recommended for the logistic model,as well as the reasonable water consumption and each growth index value for summer maize.These results will be helpful for predicting the growth and yield of summer maize.展开更多
The North China Plain(NCP)is a major grain production area in China,but the current winter wheatsummer maize system has resulted in a large water deficit.This water-shortage necessitates the improvement of crop water ...The North China Plain(NCP)is a major grain production area in China,but the current winter wheatsummer maize system has resulted in a large water deficit.This water-shortage necessitates the improvement of crop water productivity in the NCP.A crop water model,AquaCrop,was adopted to investigate yield and water productivity(WP)for rain-fed summer maize on the piedmont of the NCP.The data sets to calibrate and validate the model were obtained from a 3-year(2011–2013)field experiment conducted on the Yanshan piedmont of the NCP.The range of root mean square error(RMSE)between the simulated and measured biomass was 0.67–1.25 t·hm^(–2),and that of relative error(RE)was 9.4%–15.4%,the coefficient of determination(R^(2))ranged from 0.992 to 0.994.The RMSE between the simulated and measured soil water storage at depth of 0–100 cm ranged from 4.09 to 4.39 mm;and RE and R^(2) in the range of 1.07%–1.20%and 0.880–0.997,respectively.The WP as measured by crop yield per unit evapotranspiration was 2.50–2.66 kg·m^(–3).The simulated impact of long-term climate(i.e.,1980–2010)and groundwater depth on crop yield and WP revealed that the higher yield and WP could be obtained in dry years in areas with capillary recharge from groundwater,and much lower values elsewhere.The simulation also suggested that supplementary irrigation in areas without capillary groundwater would not result in groundwater over-tapping since the precipitation can meet the water required by both maize and ecosystem,thus a beneficial outcome for both food and ecosystem security can be assured.展开更多
Hybrids and planting density are the main factors affecting maize lodging resistance.Here,we aimed to elucidate the mechanism of the regulation of maize lodging resistance by comparing two hybrids at various planting ...Hybrids and planting density are the main factors affecting maize lodging resistance.Here,we aimed to elucidate the mechanism of the regulation of maize lodging resistance by comparing two hybrids at various planting densities from the perspective of lignin metabolism.Our results showed that compared to lodging-susceptible hybrid Xundan 20(XD20),lodging-resistant hybrid Denghai 605(DH605)showed a lower center of gravity and culm morphological characteristics that contributed to the higher lodging resistance of this hybrid.Lignin content,activities of key lignin synthesis-related enzymes and G-,S-and H-type monomer contents were significantly higher in hybrid DH605 than in hybrid XD20.Stalk mechanical strength,lignin accumulation and enzyme activity decreased significantly with increasing planting density in the two hybrids.While G-type monomers first decreased with increasing planting density but then remained stable,S-type monomers showed a decreasing trend,and H-type monomers showed an increasing trend.Correlation analysis showed that lodging rate was significantly correlated with plant traits and lignin metabolism.Therefore,maize hybrids characterized by high lignin accumulation,high lignin synthesis-related activities,high S-type monomer content,low center of gravity,high stem puncture strength,high cortical thickness,and small vascular bundle area are more resistant to lodging.High planting densities reduce stalk lignin accumulation,relevant enzyme activities and mechanical strength,thereby,ultimately increasing the lodging rate significantly.展开更多
Ammonia (NH_3) emissions should be mitigated to improve environmental quality.Croplands are one of the largest NH_3sources,they must be managed properly to reduce their emissions while achieving the target yields.Here...Ammonia (NH_3) emissions should be mitigated to improve environmental quality.Croplands are one of the largest NH_3sources,they must be managed properly to reduce their emissions while achieving the target yields.Herein,we report the NH_3 emissions,crop yield and changes in soil fertility in a long-term trial with various fertilization regimes,to explore whether NH_3 emissions can be significantly reduced using the 4R nutrient stewardship (4Rs),and its interaction with the organic amendments (i.e.,manure and straw) in a wheat–maize rotation.Implementing the 4Rs significantly reduced NH_3 emissions to 6 kg N ha~(–1) yr~(–1) and the emission factor to 1.72%,without compromising grain yield (12.37 Mg ha~(–1) yr~(–1))and soil fertility (soil organic carbon of 7.58 g kg~(–1)) compared to the conventional chemical N management.When using the 4R plus manure,NH_3 emissions (7 kg N ha~(–1) yr~(–1)) and the emission factor (1.74%) were as low as 4Rs,and grain yield and soil organic carbon increased to 14.79 Mg ha~(–1) yr~(–1) and 10.09 g kg~(–1),respectively.Partial manure substitution not only significantly reduced NH_3 emissions but also increased crop yields and improved soil fertility,compared to conventional chemical N management.Straw return exerted a minor effect on NH_3 emissions.These results highlight that 4R plus manure,which couples nitrogen and carbon management can help achieve both high yields and low environmental costs.展开更多
基金supported by the University Youth Innovation Science and Technology Support Program of Shandong Province(2021KJ073)the Postdoctoral Innovation Program of Shandong Province(202003039)China Agriculture Research System(CARS-02-21).
文摘The purpose of this study was to identify the physiological mechanism underlying the effects of high temperature and waterlogging on summer maize.The stem development and yield of the maize hybrid Denghai 605 in response to high-temperature stress,waterlogging stress,and their combination applied for six days at the third-leaf,sixth-leaf,and tasseling stages were recorded.The combined stresses reduced lignin biosynthetic enzyme activity and lignin accumulation,leading to abnormal stem development.Reduction of the area and number of vascular bundles in stems led to reduced dry matter accumulation and allocation.Decreased grain dry weight at all three stages reduced grain yield relative to a control.In summary,high temperature,waterlogging,and their combined stress impaired stem development and grain yield of summer maize.The combined stresses were more damaging than either stress alone.
基金This study was funded by the National Key Research and Development Program of China(2021YFD1700900).
文摘Phosphorus(P)is a nonrenewable resource and a critical element for plant growth that plays an important role in improving crop yield.Excessive P fertilizer application is widespread in agricultural production,which not only wastes phosphate resources but also causes P accumulation and groundwater pollution.Here,we hypothesized that the apparent P balance of a crop system could be used as an indicator for identifying the critical P input in order to obtain a high yield with high phosphorus use efficiency(PUE).A 12-year field experiment with P fertilization rates of 0,45,90,135,180,and 225 kg P_(2)O_(5)ha^(-1)was conducted to determine the crop yield,PUE,and soil Olsen-P value response to P balance,and to optimize the P input.Annual yield stagnation occurred when the P fertilizer application exceeded a certain level,and high yield and PUE levels were achieved with annual P fertilizer application rates of 90-135 kg P_(2)O_(5)ha^(-1).A critical P balance range of 2.15-4.45 kg P ha^(-1)was recommended to achieve optimum yield with minimal environmental risk.The critical P input range estimated from the P balance was 95.7-101 kg P_(2)O_(5)ha^(-1),which improved relative yield(>90%)and PUE(90.0-94.9%).In addition,the P input-output balance helps in assessing future changes in Olsen-P values,which increased by 4.07 mg kg^(-1)of P for every 100 kg of P surplus.Overall,the P balance can be used as a critical indicator for P management in agriculture,providing a robust reference for limiting P excess and developing a more productive,efficient and environmentally friendly P fertilizer management strategy.
基金the National Natural Science Foundation of China(3117 1497)the National Basic Research Program of China(973 Program,2011CB100105)+1 种基金the National Food Science and Technology of High Yield Program of China(2011BAD16B09)the Special Fund for Agro-scientific Research in the Public Interest of China(201203096)
文摘Planting at an optimum density and supplying adequate nitrogen(N) to achieve higher yields is a common practice in crop production, especially for maize(Zea mays L.); however, excessive N fertilizer supply in maize production results in reduced N use efficiency(NUE) and severe negative impacts on the environment. This research was conducted to determine the effects of increased plant density and reduced N rate on grain yield, total N uptake, NUE, leaf area index(LAI), intercepted photosynthetically active radiation(IPAR), and resource use efficiency in maize. Field experiments were conducted using a popular maize hybrid Zhengdan 958(ZD958) under different combinations of plant densities and N rates to determine an effective approach for maize production with high yield and high resource use efficiency. Increasing plant density was clearly able to promote N absorption and LAI during the entire growth stage, which allowed high total N uptake and interception of radiation to achieve high dry matter accumulation(DMA), grain yield, NUE, and radiation use efficiency(RUE). However, with an increase in plant density, the demand of N increased along with grain yield. Increasing N rate can significantly increase the DMA, grain yield, LAI, IPAR, and RUE. However, this increase was non-linear and due to the input of too much N fertilizers, the efficiency of N use at NCK(320 kg ha^(–1)) was low. An appropriate reduction in N rate can therefore lead to higher NUE despite a slight loss in grain production. Taking into account both the need for high grain yield and resource use efficiency, a 30% reduction in N supply, and an increase in plant density of 3 plants m^(–2), compared to LD(5.25 plants m^(–2)), would lead to an optimal balance between yield and resource use efficiency.
基金fnancially supported by the National Key Research and Development Program of China(2018YFD0300704)the Special Funds for Public Welfare Industry(Agriculture)Research,China(201203029)+1 种基金the Open Foundation of State Key Laboratory of Crop Biology in China(2019KF03)the Open Foundation of Chinese Academy of Agricultural Sciences,China/Key Laboratory of Crop Water Use and Regulation,Ministry of Agriculture and Rural Affairs,China(FIRI2019-02-0103)。
文摘Compared to other crops,maize production demands relatively high temperatures.However,temperatures exceeding 35℃lead to adverse effects on maize yield.High temperatures(≥35℃)are consistently experienced by summer maize during its reproductive growth stage in the North China Plain,which is likely to cause irreversible crop damage.This study investigated the effects of elevating temperature(ET)treatment on the yield component of summer maize,beginning at the 9th unfolding leaf stage and ending at the tasseling stage.Results demonstrated that continuous ET led to a decrease in the elongation rate and activity of silks and an elongated interval between anthesis and silking stages,and eventually decreased grain number at ear tip and reduced yield.Although continuous ET before tasseling damaged the anther structure,reduced pollen activity,delayed the start of the pollen shedding stage,and shortened the pollen shedding time,it was inferred,based on phenotypical and physiological traits,that continuous ET after the 9th unfolding leaf stage influenced ears and therefore may have more significant impacts.Overall,when maize plants were exposed to ET treatment in the ear reproductive development stage,the growth of ears and tassels was blocked,which increased the occurrence of barren ear tips and led to large yield losses.
基金This study was funded by the National Natural Science Foundation of China(51979235,51909221)the Agricultural Science and Technology Innovation Integration Promotion Project of Shaanxi Province,China(SXNYLSYF2019-01)+1 种基金the China Postdoctoral Science Foundation(2019M650277)the Natural Science Basic Research Plan in Shaanxi Province,China(2020JQ-276).
文摘Ridge-furrow film mulching has been proven to be an effective water-saving and yield-improving planting pattern in arid and semi-arid regions.Drought is the main factor limiting the local agricultural production in the Loess Plateau of China.In this study,we tried to select a suitable ridge-furrow mulching system to improve this situation.A two-year field experiment of summer maize(Zea mays L.)during the growing seasons of 2017 and 2018 was conducted to systematically analyze the effects of flat planting with no film mulching(CK),ridge-furrow with ridges mulching and furrows bare(RFM),and double ridges and furrows full mulching(DRFFM)on soil temperature,soil water storage(SWS),root growth,aboveground dry matter,water use efficiency(WUE),and grain yield.Both RFM and DRFFM significantly increased soil temperature in ridges,while soil temperature in furrows for RFM and DRFFM was similar to that for CK.The largest SWS was observed in DRFFM,followed by RFM and CK,with significant differences among them.SWS was lower in ridges than in furrows for RFM.DRFFM treatment kept soil water in ridges,resulting in higher SWS in ridges than in furrows after a period of no water input.Across the two growing seasons,compared with CK,RFM increased root mass by 10.2%and 19.3%at the jointing and filling stages,respectively,and DRFFM increased root mass by 7.9%at the jointing stage but decreased root mass by 6.0%at the filling stage.Over the two growing seasons,root length at the jointing and filling stages was respectively increased by 75.4%and 58.7%in DRFFM,and 20.6%and 30.2%in RFM.Relative to the jointing stage,the increased proportions of root mass and length at the filling stage were respectively 42.8%and 94.9%in DRFFM,63.2%and 115.1%in CK,and 76.7%and 132.1%in RFM,over the two growing seasons,showing that DRFFM slowed down root growth while RFM promoted root growth at the later growth stages.DRFFM treatment increased root mass and root length in ridges and decreased them in 0-30 cm soil layer,while RFM increased them in 0-30 cm soil layer.Compared with CK,DRFFM decreased aboveground dry matter while RFM increased it.Evapotranspiration was reduced by 9.8%and 7.1%in DRFFM and RFM,respectively,across the two growing seasons.Grain yield was decreased by 14.3%in DRFFM and increased by 13.6%in RFM compared with CK over the two growing seasons.WUE in CK was non-significantly 6.8%higher than that in DRFFM and significantly 22.5%lower than that in RFM across the two growing seasons.Thus,RFM planting pattern is recommended as a viable water-saving option for summer maize in the Loess Plateau of China.
基金supported by the National Natural Science Foundation of China(31801296)China Agriculture Research System of MOF and MARA(CARS-02-18)+1 种基金the National Key Research and Development Program of China(2017YFD0300304)the Postdoctoral Innovation Program of Shandong Province(202003039)。
文摘Stable yield of staple grains must be ensured to satisfy food demands for daily dietary energy requirements against the backdrop of global climate change. Summer maize, a staple crop, suffers severe yield losses due to extreme rainfall events, threatening food security. A randomized block experiment with four treatments: control, no water stress(CK);waterlogging for 6 days at the third leaf, sixth leaf stage,and 10 th day after tasseling, was conducted to investigate the mechanism of waterlogging-induced yield losses of summer maize. Waterlogging delayed plant growth and impaired tassel and ear differentiation,leading to high grain yield losses of Denghai 605(DH605). Waterlogging at third leaf(V3) stage reduced the photosynthesis of DH605, reducing total dry matter weight. Waterlogging at V3 stage reduced sucrose-cleaving enzymes activities in spike nodes and ears, reducing the carbon partitioned to ears(–53.1%), shanks(–46.5%), and ear nodes(–71.5%) but increasing the carbon partitioned to ear leaves(9.6%) and tassels(43.9%) in comparison with CK. The reductions in total carbon assimilate together with the reduced carbon partitioning to ears resulted in poor development of spikes(with respectively 15.2%and 20.6% reductions in total florets and fertilized florets) and lengthened the anthesis–silking interval by around 1 day, leading to high yield losses.
基金We are grateful for grants from the National Basic Research Program of China(2015 CB 150404)the earmarked fund for China Agriculture Research System(CARS-02-18)the Funds of Shandong“Double Tops”Program,China(SYL2017YSTD02).
文摘Compared with single agronomic practices management during grain formation, knowledge about integrated agronomic practices management on grain-filling characteristics and physiological function of endogenous hormones was limited. In order to clarify this issue, two field experiments, integrated agronomic practices management(IAPM), T1(local conventional cultivation practices), T2(an optimized combination of cropping systems and fertilizer treatment), T3(treatment based on high-yield studies), and T4(further optimized combination of cropping systems and fertilizer treatment), and nitrogen rate testing(NAT)(four nitrogen rates, 0, 129.0, 184.5, and 300.0 kg N ha–1) were performed with summer maize hybrid Zhengdan 958(ZD958). Results showed that with increased nitrogen rate, the endogenous hormone balance was promoted and the grain-filling characteristics were improved sufficiently to resulting in a significant increase in grain yield. However, the grain-filling characteristics deteriorated and yield was reduced with excessive nitrogen fertilization. However, IAPM could promote hormone balance and improve grain filling characteristic. The indole-3-acetic acid(IAA), zeatin riboside(ZR), and gibberellin(GA3) contents under T2 and T4 treatments were higher and the abscisic acid(ABA) content was lower, and the ZR and GA3 contents under T3 were higher than those under T1. Those resulted in the maximum grain-filling rate(Wmax) and the active grain-filling period(P) under T2, T3 and T4 were significantly increased than those under T1, and hence promoted kernel weight and grain yield. So IAPM promoted hormone balance by improving tillage model, optimizing fertilizer rate and fertilization period, appropriately increasing planting density and delaying harvest, which promoted grain filling rate and lengthened active grain-filling period, finally increased grain yield.
基金Supported by National Key Research and Development Program of China(2017FYD0101406)Zhoukou Comprehensive Test Station of Henan Provincial Corn Industry Technology System(HARS-22-02-Z5)。
文摘[Objectives] This study was conducted to verify the field application effect of slow-release nitrogen fertilizer on summer maize in Shajiang black soil area by simultaneous sowing and fertilization, and explore the application scope and nitrogen metabolism mechanism, so as to lay a foundation for fertilizer reduction and efficiency improvement. [Methods] With maize variety Beiqing 340 and sulfur-coated urea as experimental materials, five nitrogen application levels were set, namely, control (C0), slow-release nitrogen 70 kg/hm^(2) (C70), slow-release nitrogen 140 kg/hm^(2) (C140), slow-release nitrogen 210 kg/hm^(2) (C210) and slow-release nitrogen 280 kg/hm^(2) (C280). The phosphorus and potassium fertilizers were all in accordance with the unified standard. [Results] With the application rate of slow-release nitrogen increasing, the nitrogen accumulation in organs increased first and then decreased after tasseling stage of maize. In order to reduce the fertilizing amount and increase efficiency, 210 kg/hm^(2) of slow-release nitrogen fertilizer was the best fertilizing amount for summer maize in Shajiang black soil area. [Conclusions] This study provides reference for fertilizer reduction, efficiency improvement and sustainable development of summer maize in Shajiang black soil area.
基金jointly supported by the National Key Research and Development Program of China(2016YFD0300106)the National Natural Science Foundation of China(41501047 and41330531)the China Special Fund for Meteorological Research in the Public Interest(Major projects)(GYHY201506001-3)
文摘Evaluating climatic suitability of crop cultivation lays a foundation for agriculture coping with climate change scientifically. Herein, we analyse changes in the climatically suitable distribution of summer maize cultivation in China at 1.5℃(GW1.5) and 2.0℃(GW2.0) global warming in the future according to the temperature control targets set by the Paris Agreement. Compared with the reference period (1971- 2000), the summer maize cultivation climatically suitable region (CSR) in China mainly shifts eastwards, and its acreage significantly decreases at both GW1.5 and GW2.0. Despite no dramatic changes in the CSR spatial pattern, there are considerable decreases in the acreages of optimum and suitable regions (the core of the main producing region), indicating that half-a-degree more global warming is unfavourable for summer maize production in China's main producing region. When the global warming threshold increases from GW1.5 to GW2.0, the centres-of-gravity of optimum areas shift northeastward under RCP4.5 and RCP8.5, the centres-of-gravity of both suitable and less suitable areas shift northwestward, though the northward trend is more prominent for the less suitable areas, and the centre-of-gravity of unsuitable areas shifts southeastward. Generally, half-a-degree more global warming drives the cultivable areas of summer maize to shift northward in China, while the west region shows a certain potential for expansion of summer maize cultivation.
基金This research was financially supported by Jiangxi Educational Bureau Science-Technology Research Program(GJJ170981)National Natural Science Foundation of China(51709144)and Farmland Irrigation Research Institute,Chinese Academy of Agricultural Sciences(FIRI2017-22-01).
文摘In order to explore the appropriate irrigation schedule for summer maize,a field experiment was conducted in 2013 in Lubotan of Shaanxi Province.Soil water content,soil salinity,soil hydraulic parameters,crop growth parameters and summer maize yield were measured in the experiment.The SWAP model was calibrated based on field experiment observation data in 2013.The SWAP model was used to simulate and optimize irrigation schedule for summer maize after calibration.The results showed that model simulation results of soil water content,soil salinity and summer maize yield agreed well with the measured values.The Root Mean Square Error(RMSE)and Mean Relative Error(MRE)were within the allowable error ranges.The RMSE values were all lower than 0.05 cm3/cm3 and the MRE values were lower than 15%in soil water content calibration.The RMSE values were all lower than 0.1 mg/cm3 and the MRE values were lower than 20%in soil salinity calibration.The RMSE and MRE values were 1299.6 kg/hm2 and 15.26%in summer maize yield calibration.The model parameters suitable for the study area were obtained in calibration.The SWAP model could be used to simulate and optimize irrigation schedule for summer maize after calibration.The SWAP model was used to simulate soil water-salt balance,summer maize yield and water use efficiency under different irrigation schedules.The model simulation results for different irrigation schedules indicated that the optimal irrigation schedules of summer maize were three times each for jointing stage(July 5),heading stage(August 5)and grain filling stage(August 30)with irrigation amount of 128 mm,128 mm and 96 mm,respectively.The optimal irrigation quota was 352.0 mm for summer maize in the study area.
基金financially supported by the National Natural Science Foundation of China(Grant No.41830754,51979220,5210090651)Xinjiang Water Special Project(2020.D-001).
文摘The growing degree days(GDD)is an important factor for crop growth because it affects dry matter formation and crop yield.In this study,the universal logistic models were established employing GDD and the relative GDD(RGDD)as the main parameters to characterize summer maize growth indices such as plant height(H),leaf area index(LAI),and dry matter accumulation(DMA).The relationships were analyzed between the growth indices,harvest index(HI),water consumption,and yield in maize.By considering China as an example,the results showed that the logistic model performed well at simulating the changes in the summer maize growth indices in different regions and the universal model parameters were within specific ranges.Furthermore,the logistic model with RGDD as the independent variable was more suitable for modeling summer maize growth in large areas than GDD.The relationship between the maximum LAI and HI was described by a quadratic polynomial function.HI was optimal(0.53)when the maximum LAI was about 5.13.The maximum LAI,maximum H,and maximum DMA could be described by a quadratic polynomial function of water consumption during the growing season.The summer maize yield could be predicted with a binary quadratic equation using the maximum GDD and water consumption.This study confirmed that a logistic model can be used to establish a universal growth model for summer maize in large areas.Reasonable ranges of parameters were recommended for the logistic model,as well as the reasonable water consumption and each growth index value for summer maize.These results will be helpful for predicting the growth and yield of summer maize.
基金The authors are grateful for financial support provided by the IAEA(CRP14483)China National Science and Technology Pillar Program(2012BAD05B02).
文摘The North China Plain(NCP)is a major grain production area in China,but the current winter wheatsummer maize system has resulted in a large water deficit.This water-shortage necessitates the improvement of crop water productivity in the NCP.A crop water model,AquaCrop,was adopted to investigate yield and water productivity(WP)for rain-fed summer maize on the piedmont of the NCP.The data sets to calibrate and validate the model were obtained from a 3-year(2011–2013)field experiment conducted on the Yanshan piedmont of the NCP.The range of root mean square error(RMSE)between the simulated and measured biomass was 0.67–1.25 t·hm^(–2),and that of relative error(RE)was 9.4%–15.4%,the coefficient of determination(R^(2))ranged from 0.992 to 0.994.The RMSE between the simulated and measured soil water storage at depth of 0–100 cm ranged from 4.09 to 4.39 mm;and RE and R^(2) in the range of 1.07%–1.20%and 0.880–0.997,respectively.The WP as measured by crop yield per unit evapotranspiration was 2.50–2.66 kg·m^(–3).The simulated impact of long-term climate(i.e.,1980–2010)and groundwater depth on crop yield and WP revealed that the higher yield and WP could be obtained in dry years in areas with capillary recharge from groundwater,and much lower values elsewhere.The simulation also suggested that supplementary irrigation in areas without capillary groundwater would not result in groundwater over-tapping since the precipitation can meet the water required by both maize and ecosystem,thus a beneficial outcome for both food and ecosystem security can be assured.
基金The authors gratefully acknowledge the earmarked fund for China Agriculture Research System of MOF and MARA(CARS-02)the National Key Research and Development Program of China(2017YFD0300304)the National Natural Science Fundation of China(31671629).
文摘Hybrids and planting density are the main factors affecting maize lodging resistance.Here,we aimed to elucidate the mechanism of the regulation of maize lodging resistance by comparing two hybrids at various planting densities from the perspective of lignin metabolism.Our results showed that compared to lodging-susceptible hybrid Xundan 20(XD20),lodging-resistant hybrid Denghai 605(DH605)showed a lower center of gravity and culm morphological characteristics that contributed to the higher lodging resistance of this hybrid.Lignin content,activities of key lignin synthesis-related enzymes and G-,S-and H-type monomer contents were significantly higher in hybrid DH605 than in hybrid XD20.Stalk mechanical strength,lignin accumulation and enzyme activity decreased significantly with increasing planting density in the two hybrids.While G-type monomers first decreased with increasing planting density but then remained stable,S-type monomers showed a decreasing trend,and H-type monomers showed an increasing trend.Correlation analysis showed that lodging rate was significantly correlated with plant traits and lignin metabolism.Therefore,maize hybrids characterized by high lignin accumulation,high lignin synthesis-related activities,high S-type monomer content,low center of gravity,high stem puncture strength,high cortical thickness,and small vascular bundle area are more resistant to lodging.High planting densities reduce stalk lignin accumulation,relevant enzyme activities and mechanical strength,thereby,ultimately increasing the lodging rate significantly.
基金supported by the Hainan Key Research and Development Project, China (ZDYF2021XDNY184)the Hainan Provincial Natural Science Foundation of China (422RC597)+2 种基金the National Natural Science Foundation of China (41830751)the Hainan Major Science and Technology Program, China (ZDKJ2021008)the Hainan University Startup Fund,China (KYQD(ZR)-20098)。
文摘Ammonia (NH_3) emissions should be mitigated to improve environmental quality.Croplands are one of the largest NH_3sources,they must be managed properly to reduce their emissions while achieving the target yields.Herein,we report the NH_3 emissions,crop yield and changes in soil fertility in a long-term trial with various fertilization regimes,to explore whether NH_3 emissions can be significantly reduced using the 4R nutrient stewardship (4Rs),and its interaction with the organic amendments (i.e.,manure and straw) in a wheat–maize rotation.Implementing the 4Rs significantly reduced NH_3 emissions to 6 kg N ha~(–1) yr~(–1) and the emission factor to 1.72%,without compromising grain yield (12.37 Mg ha~(–1) yr~(–1))and soil fertility (soil organic carbon of 7.58 g kg~(–1)) compared to the conventional chemical N management.When using the 4R plus manure,NH_3 emissions (7 kg N ha~(–1) yr~(–1)) and the emission factor (1.74%) were as low as 4Rs,and grain yield and soil organic carbon increased to 14.79 Mg ha~(–1) yr~(–1) and 10.09 g kg~(–1),respectively.Partial manure substitution not only significantly reduced NH_3 emissions but also increased crop yields and improved soil fertility,compared to conventional chemical N management.Straw return exerted a minor effect on NH_3 emissions.These results highlight that 4R plus manure,which couples nitrogen and carbon management can help achieve both high yields and low environmental costs.
