Drought stress orchestrates a phosphorylation-dependent signaling cascade that reprograms transcriptional networks to enhance crop resilience.Through a large-scale transgenic screening,we identified ZmCRK5A,a Ca^(2+)-...Drought stress orchestrates a phosphorylation-dependent signaling cascade that reprograms transcriptional networks to enhance crop resilience.Through a large-scale transgenic screening,we identified ZmCRK5A,a Ca^(2+)-independent calcium-dependent protein kinase(CDPK)-related kinase,as a master regulator of drought tolerance in maize.Mechanistically,ZmCRK5A directly phosphorylates the MYB transcriptional repressor ZmSMH4(Single MYB Histone 4)at three conserved serine residues(Ser42/43/59)within its SANT domain,as demonstrated by in vitro kinase assays and site-directed mutagenesis.This post-translational modification abolishes Zm SMH4's DNA-binding capacity to ACC cis-elements,thereby de-repressing the potassium influx channel gene Zm KCH1(K^(+)Channel 1).Functional validation revealed that Zm KCH1 overexpression confers drought resilience through optimized stomatal dynamics and water retention,whereas clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)-generated zmkch1 mutants display hypersensitivity to water deficit.Crucially,field evaluations demonstrated preserved grain yield alongside enhanced drought tolerance in plants with activated Zm CRK5A-Zm SMH4-Zm KCH1 signaling.Our findings delineate a kinase-transcription factor-ion channel axis that dynamically fine-tunes drought responses while maintaining productivity,providing a strategic framework for engineering stress-adapted crops without yield penalties.展开更多
Persistent overcast rain was an essential limiting factor for summer maize production,of which immediate impact was the dual pressure of waterlogging and shading.However,the mechanisms underlying independent and combi...Persistent overcast rain was an essential limiting factor for summer maize production,of which immediate impact was the dual pressure of waterlogging and shading.However,the mechanisms underlying independent and combined effects of waterlogging and shading on maize yield losses remain understudied,particularly across different growth stages.Denghai 605(DH605)was selected to be subjected shading,waterlogging,and their combined stress at the 3rd leaf stage(V3),the 6th leaf stage(V6),and tasseling stage(VT).Results showed that shading,waterlogging and their combination significantly restricted leaf area expansion,reduced leaf net photosynthetic rate(P_(n))and net assimilation rate(NAR),thereby decreasing the crop growth rate(CGR)and biomass accumulation.Additionally,compared to control,the process of lignin synthesis was inhibited under stressed treatment,resulting in diminished stem mechanical strength and impaired vascular system development,which substantially reduced assimilate remobilization efficiency to the ear and ultimate grain yield.Waterlogging and combined stresses exhibited maximum impact at the V3 stage,followed by V6 and VT stages,while shading effects were most pronounced at the VT stage,followed by V6 and V3 stages.Moreover,the compound stress exacerbated the damage brought about by a single stress.As climate change is projected to increase the frequency of multiple abiotic stress occurrences,these findings provide valuable insights for future summer maize breeding research under persistent rainfall conditions.展开更多
High temperature stress (HT) significantly reduces maize yield by impairing starch accumulation in kernels.However,the mechanism by which HT affects starch synthesis remains controversial-whether through reduced assim...High temperature stress (HT) significantly reduces maize yield by impairing starch accumulation in kernels.However,the mechanism by which HT affects starch synthesis remains controversial-whether through reduced assimilate supply or direct inhibition on kernel metabolism.To clarify these mechanisms,a heat-sensitive maize hybrid,Xianyu 335 (XY),was exposed to 30℃/20℃ (maximum/minimum temperature,control) and 40℃/30℃ for seven consecutive days during the seed setting stage.Synchronous pollination (SP),apical pollination (AP),and shading treatments were applied to manipulate the inherent source–sink ratio in maize plants.Results showed that apical kernel weight decreased by 11.9%under 40℃ in the SP treatment.The ^(13)C content,starch accumulation,and cell-wall invertase (CWIN) activity also declined by 15.9,36.7,and 16.4%,respectively,under HT.In the shading treatment,40℃/30℃ caused even greater reductions in^(13)C content,starch accumulation,and CWIN activity due to diminished assimilate supply.Conversely,in the AP treatment,starch content and CWIN activity increased by 22.0 and 18.5%,respectively,under 40℃/30℃,resulting in kernel weight and ^(13)C content similar to those in SP and shading treatments regardless of temperature.Consistent with apical kernels under AP,HT did not negatively affect middle kernels in either SP or shading treatments,as kernel weight and starch content remained unchanged under HT.Although all kernels were exposed to the same HT or control environment,their responses varied a lot.The impaired starch synthesis in apical kernels under HT was rescued by increasing carbon supply via AP treatment.The contrasting performance among middle kernels,apical kernels under AP,and apical kernels under SP or shading indicates that reduced carbon supply is a critical factor underlying inhibited starch accumulation.Our findings provide a theoretical basis for further understanding kernel abortion under HT.展开更多
Maize/soybean intercropping systems are commonly used in developing countries,but few studies have been performed to elucidate the differences in nutrient efficiency and rhizosphere microbiome,especially when maize is...Maize/soybean intercropping systems are commonly used in developing countries,but few studies have been performed to elucidate the differences in nutrient efficiency and rhizosphere microbiome,especially when maize is intercropped with different soybean varieties.In this study,field experiments were conducted to compare the growth and yield of two soybean(Glycine max)varieties,BD2 and YC03-3,and one maize(Zea mays)variety,Huazhen,in mono-cropped and intercropped cultures.The plant biomass and N content of both crops in BD2/maize intercropping were significantly improved compared to their monoculture,but no such effects were observed in the plants of YC03-3/maize intercropping.The yield of BD2 intercropped with maize exhibited a 37.5%increment above that of BD2 in monoculture.Moreover,19.2-29.1%longer root length of maize and 19.0-39.4%larger root volume of BD2 were observed in BD2/maize intercropping than in monoculture,but no growth advantage was observed in YC03-3/maize intercropping.Maize showed root avoidance when intercropped with BD2,but space competition when intercropped with YC03-3.16S rRNA amplicon sequencing showed that compared with the monoculture system,rhizobacteria community composition in BD2/maize intercropping changed more significantly than that of the YC03-3/maize intercropping system.In BD2/maize intercropping,most of the rhizobacteria community biomarker bacteria of BD2 were positively correlated with plant biomass,as well as plant P and N content.Maize tended to recruit Rhizobiales and Proteobacteria,which showed positive correlation with plant biomass and N content,respectively,as well as soil available N.In conclusion,soybean varieties determined the advantages of maize/soybean intercropping through root-root interactions and modification of rhizobacteria communities.Our insight emphasizes a linkage between root traits and the rhizobacteria community,which shows the importance of optimizing intercropping systems by selection of appropriate crop varieties.展开更多
Carbohydrate partitioning from source to sink tissues is essential for plant growth and development.However,in maize(Zea mays L.),the molecular mechanisms by which callose synthase genes regulate this process remain l...Carbohydrate partitioning from source to sink tissues is essential for plant growth and development.However,in maize(Zea mays L.),the molecular mechanisms by which callose synthase genes regulate this process remain largely unexplored.This study demonstrates that mutation of maize callose synthase12(Zm Cals12)results in increased carbohydrate accumulation in photosynthetic leaves but decreased carbohydrate content in sink tissues,leading to plant dwarfing and male sterility.Histochemical β-glucuronidase(GUS)activity assay and m RNA in situ hybridization(ISH)revealed that Zm Cals12 expression mainly occurs in the vascular transport system.Zm Cals12 loss-of-function decreased callose synthase activity and callose deposition in plasmodesmatas(PDs)and surrounding phloem cells(PCs)of the vascular bundle.The drop-and-see(DANS)assay indicated reduced PD permeability in photosynthetic cells and diminished transport competence of leaf veins in Zmcals12 mutants,resulting in decreased symplastic transport.Paraffin section analysis revealed that less-developed vascular cells(VCs)in Zmcals12 mutants likely disrupted sugar transport,contributing to the pleiotropic phenotype.Furthermore,impaired sugar transport inhibited internode development by suppressing auxin(IAA)biosynthesis and signaling in Zmcals12 mutant.These findings elucidate the mechanism by which Zm Cals12-mediated callose deposition and symplastic transport regulate maize growth and development.展开更多
Sand dust belts span approximately one-fifth of the global land surface.In these regions,dust tends to settle on vegetation surfaces,altering the observed reflectance and affecting remote sensing detections.To enhance...Sand dust belts span approximately one-fifth of the global land surface.In these regions,dust tends to settle on vegetation surfaces,altering the observed reflectance and affecting remote sensing detections.To enhance the accuracy of maize growth monitoring in dust-affected regions,this study aims to quantify the effect of sand dust retention on maize during the tasseling stage in the Kashgar Prefecture,Xinjiang Uygur Autonomous Region,China,by analyzing changes in canopy reflectance and vegetation indices.First,field sampling was conducted to measure the key canopy structure parameters and dust retention levels of maize,and laboratory spectral measurements were performed on leaf spectral properties under gradient dust retention.The measured data were then used to drive the LargE-Scale remote sensing data and image Simulation framework(LESS)model for simulating realistic maize canopy spectra across different dust levels,with validation against Sentinel-2 imagery.Second,on the basis of the simulated and satellite-derived spectra,the dust resistance of 36 common vegetation indices was systematically evaluated,and new robust dust-resistant indices were developed.The results showed that compared with dust-free maize,the canopy reflectance of dust-retained maize followed an increase–decrease–increase pattern,with critical turning points at 735 and 1325 nm.The maximum reflectance difference of–0.11755(change rate:29.002%)occurred within the 735–1325 nm range at 24 g/m^(2)dust retention,and the minimum reflectance difference of 0.04285(change rate:148.950%)was observed in the 350–735 nm range under the same dust retention level.Among the 36 vegetation indices,only the global environment monitoring index(GEMI)and the ratio of transformed chlorophyll absorption in reflectance index to optimized soil-adjusted vegetation index(TCARI/OSAVI)exhibited dust resistance,with GEMI being effective below 6 g/m^(2)and TCARI/OSAVI remaining stable across all levels(average ratio:0.970).The newly developed indices in this study,(RE3–RE2)/(NIR–RE2),(RE3–RE2)/(RE4–RE2),and(NIR–RE2)/(RE4–RE2),retained values within the predefined dust-resistant range over the full dust retention levels of 0–24 g/m^(2),thus showing a more stable dust resistance compared with the commonly used 36 vegetation indices.Specially,(RE3–RE2)/(RE4–RE2)performed the most robustly in Sentinel-2 imagery,that is,58.020%of pixels were within the dust-resistant range,and an average ratio of 0.937 was obtained for the original-spectra index.This study provides a scientific basis for crop monitoring and management in dust-affected regions.展开更多
The exogenous plant growth regulator,diethyl aminoethyl hexanoate(DA-6),in combination with suitable varieties and planting densities,is important to increase yield in the maize-soybean strip intercropping system.To i...The exogenous plant growth regulator,diethyl aminoethyl hexanoate(DA-6),in combination with suitable varieties and planting densities,is important to increase yield in the maize-soybean strip intercropping system.To identify the role of DA-6 in mitigating high-density stress and increasing yield,we conducted a two-year field experiment examining changes in branching architecture and other yield traits of soybeans in maize-soybean strip intercropping systems.In the planting system,two soybean cultivars(ND:Nandou 25 and QH:Qihuang 34)were grown under three planting densities(D1:102,000 plants ha^(-1),D2:130,000 plants ha^(-1),D3:158,000 plants ha^(-1))with DA-6 treatments(DA0:water control;DA60:60 mg L^(-1);DA100:100 mg L^(-1)).Applying DA-6 at 60 mg L^(-1)at the fourth trifoliolate leaf stage increased soybean yield,with QH yield rising by 22.4% and 29.5% at D3 density,and ND yield by 29.5% and 30.0% at D2 density in 2022 and 2023,respectively,compared with D1 under DA0.DA-6improved photosynthesis in both varieties under D2 density,with DA60 increasing ND canopy photosynthetic rate by 15.1%-16.4% and QG by 9.1%-20.6% over two years.In ND,DA-6 enhanced branching,raising the leaf area index by 37%,branch number from 3.6 to 4.7 per plant,and total pod number by 19.7%.In QH,yield grains were mainly due to a 17% increase in the number of stem pods and a 6.5% improvement in hundred-grain weight.In the maize-soybean strip intercropping system,QH achieved a high yield by forming a high-density(D2 to D3)main stem pod,and ND by combining moderate density(D1 to D2)with DA-6-induced branching.展开更多
In view of the existing composite planting cannot do independent control of fertilizer rate for each row,and fertilizer is easy to moisture solidification caking and rely on a single way to measure the speed of inaccu...In view of the existing composite planting cannot do independent control of fertilizer rate for each row,and fertilizer is easy to moisture solidification caking and rely on a single way to measure the speed of inaccurate problems,a split-drive variable fertilizer application system was designed for soybean and maize strip cropping composites.It includes roller crushing bi-directional spiral fertilizer discharger,split-drive variable fertilizer application system and‘GNSS+encoder’dual speed measurement system.By modeling agglomerated fertilizer particles,discrete element simulation was carried out to analyze the crushing effect.The speed measurement error variation folds of both GNSS and encoder under different speed conditions were obtained through field speed measurement tests.Finally,4.5 km/h was identified as the switching point between the two speed measurements.Through bench testing,a mathematical relationship model was developed for the soybean and maize belts in terms of‘Fertilizer Application Rate-Operating Travel Speed-Metering Mechanism Rotor Speed’,and the results are presented in the table below.Fertilizer discharge consistency was verified for fertilizer dischargers.Field trials were conducted,and the results show:The soybean belt had a maximum error of 4.81%at a fertilizer application rate of 150 kg/hm2 and an operating speed of 5 km/h;the maximum error in the corn belt was 4.67%at a fertilizer application rate of 600 kg/hm2 and operating speed of 4 km/h.Both have a maximum error of less than 5%,which meets the requirements for variable fertilizer application.展开更多
[Objective] The experiment was aimed to explore character variation between different families after DNA introduction and select variant plants with good stability. [Method] The method of pollen-tube-pathway was used ...[Objective] The experiment was aimed to explore character variation between different families after DNA introduction and select variant plants with good stability. [Method] The method of pollen-tube-pathway was used to introduce total DNA of soybean into normal maize inbred line 7313 for selecting generation by generation. When field characters of maize, grain colors, grain traits and panicle axis colors were stable, the crude protein, gliadin, glutelin and oil content of grains which were selected from variant strains were detected and compared. [Result] The grain crude protein, gliadin, glutelin and oil content of line 26h-4-3 were significantly different from these of control treatment. The increments of D3 and D4 generation were 10.34% and 26.70%, 6.58% and 6.28%, 15.09% and 70.34%, 55.82% and 51.52% respectively. All indexes of line 26h-3-1 were also higher than these of control treatment and the increments of D3 and D4 generation were 5.67% and 21.63%,1.91% and 2.31%, 10.85% and 62.27%,22.49% and 9.67%. [Conclusion] The crude protein, gliadin, glutelin and oil content of variant line 26h-4-3 and 26h-3-1 were stable, so variant line 26h-4-3 and 26h-3-1 were excellent variant strains which satisfied the requirement of high protein breeding.展开更多
The effects of different maize sowing dates and densities on stem and leaf morphological characters and yield of soybean in wheat/maize/soybean relaycropping system were studied. The results showed that with early sow...The effects of different maize sowing dates and densities on stem and leaf morphological characters and yield of soybean in wheat/maize/soybean relaycropping system were studied. The results showed that with early sowing of maize, the maize yield was promoted, and maize was harvested in advance, which reduced the intergrowth period with soybean and guaranteed soybean＇s proper plant height, larger stem diameter and optimal values of LAI and SLW, so that soybean yield was also increased. The effects of different maize densities on the stem and leaf of soybean mainly were significant before the maize harvest, but soybean yield under high maize density was significantly lower than that under middle and low maize density, and the highest maize yield was under middle density. Based on soybean and maize comprehensive values, the optimum combination of this experiment was sowed on March 21 and planting density was 5.25×10^4 plant/hm^2.展开更多
The high-efficiency planting mode for five crops a year of fresh edible ＂faba bean/spring maize＋soybean-autumn maize/autumn soybean＂ was introduced, and its yield and economic benefits were compared with the planti...The high-efficiency planting mode for five crops a year of fresh edible ＂faba bean/spring maize＋soybean-autumn maize/autumn soybean＂ was introduced, and its yield and economic benefits were compared with the planting mode of three crops a year of ＂faba bean-spring maize/red bean＂. The results showed that the planting method for fresh edible ＂faba bean/spring maize＋soybean-autumn maize/autumn soybean＂ was much easier to operate with the input-output ratio of about185.6%, and its yield and economic benefits were 2.09 and 1.83 times of that of the planting mode for three crops a year, significantly improving the agricultural yield and income of farmers. In addition, the cropping index of the planting mode for fresh edible fresh edible ＂faba bean/spring maize ＋soybean-autumn maize/autumn soybean＂ reached up to 350%, and planting faba bean once a year and soybean twice a year could make the biological fixation amount of nitrogen increase 350-450kg/m^2, which equaled to up to 700 kg/m^2 of urea, showing significant ecological and social benefits. Based on the comparison results, the high-yield culture techniques of the planting mode of fresh edible ＂faba bean/spring maize＋soybean-autumn maize/autumn soybean＂ were summarized.展开更多
Intercropping, particularly the combination of maize and soybeans, has been widely recognized for its potential to improve nitrogen uptake and promote sustainable agriculture. This study examines the patterns of nitro...Intercropping, particularly the combination of maize and soybeans, has been widely recognized for its potential to improve nitrogen uptake and promote sustainable agriculture. This study examines the patterns of nitrogen uptake in maize and soybean intercropping systems under different growth stages and phosphorus fertilization levels and investigates the influence of nitrogen uptake on growth parameters such as plant height, leaf area, and biomass accumulation in the maize/soybean intercrop under different phosphorus fertilization regimes. The study also collected chlorophyll samples at different growth stages of maize in monoculture and intercropping with maize or soybean. The results showed that plant height was greater in V10 in both fertilized and unfertilized treatments for intercropped maize and soybean, and chlorophyll concentration was higher in VT intercropped maize. The results also showed a higher accumulation of biomass. Understanding the growth dynamics of these plants in monoculture and intercropping systems and the impact of fertilization practices is crucial for optimizing crop productivity and sustainability in agricultural systems.展开更多
[Objective] The aim was to discuss the group dry matter accumulation and economic benefits under the patterns of intercropping maize （Zea mays L.） with soy-bean [Glycine max （L.） Merril ]. [Methods] Zhengdan-958 a...[Objective] The aim was to discuss the group dry matter accumulation and economic benefits under the patterns of intercropping maize （Zea mays L.） with soy-bean [Glycine max （L.） Merril ]. [Methods] Zhengdan-958 and Luhuang-1 were used as the testing breeds to study the effects of intercropping patterns on dry matter accumulation and transportation of maize and soybean in Huang-huai-hai. [Results] For maize, the dry matter accumulation amounts per hectare of intercropping was significant higher than that of the monoculture patterns, especial y after silking, when it reached extremely level; while for soybean, the dry matter accumulation amounts before flowering and after flowering of monocropping were al significantly higher than that of the intercropping patterns. For both maize and soybean, the transfer amounts of monocropping were al significantly or extremely significantly higher than that of intercropping; and the transfer ratio of maize intercropping was 0.59% higher than that of maize monocropping, while for soybean, it was 4.74% higher. Fitted dry matter accumulation with Logistic equation, it showed that the difference in maximum dry matter accumulation rate between maize monocropping and intercropping reached significant level, while for soybean, the maximum dry matter accumulation rate and its appearance time as wel as duration time between intercropping and monocropping were al reached significant level. The total land equivalent ratio of intercropping was 1.30. From yield and output value, the total yield of intercropping were 10.97 t/hm2, 0.64% and 326.85% higher than monocropping of maize and soy-bean, respectively. The total output value of intercropping was 25 796.23 yuan/hm2, respectively 12.67% and 104.68% higher than of maize and soybean monocropping. [Conclusion] The study lays a basis for improving grain yield and economic benefits.展开更多
Intercropping is one of the most vital practice to improve land utilization rate in China that has limited arable land resource. However, the traditional intercropping systems have many disadvantages including illogic...Intercropping is one of the most vital practice to improve land utilization rate in China that has limited arable land resource. However, the traditional intercropping systems have many disadvantages including illogical field lay-out of crops, low economic value, and labor deficiency, which cannot balance the crop production and agricultural sustainability. In view of this, we developed a novel soybean strip intercropping model using maize as the partner, the regular maize-soybean strip intercropping mainly popularized in northern China and maize-soybean relay-strip intercropping principally extended in southwestern China. Compared to the traditional maize-soybean intercropping systems, the main innovation of field lay-out style in our present intercropping systems is that the distance of two adjacent maize rows are shrunk as a narrow strip, and a strip called wide strip between two adjacent narrow strips is expanded reserving for the growth of two or three rows of soybean plants. The distance between outer rows of maize and soybean strips are expanded enough for light use efficiency improvement and tractors working in the soybean strips. Importantly, optimal cultivar screening and increase of plant density achieved a high yield of both the two crops in the intercropping systems and increased land equivalent ratio as high as 2.2. Annually alternative rotation of the adjacent maize-and soybean-strips increased the grain yield of next seasonal maize, improved the absorption of nitrogen, phosphorus, and potasium of maize, while prevented the continuous cropping obstacles. Extra soybean production was obtained without affecting maize yield in our strip intercropping systems, which balanced the high crop production and agricultural sustainability.展开更多
Intercropping is an important agronomic practice. However, assessment of intercropping systems using field experiments is often limited by time and cost. In this study, the suitability of using the DeNitrification DeC...Intercropping is an important agronomic practice. However, assessment of intercropping systems using field experiments is often limited by time and cost. In this study, the suitability of using the DeNitrification DeComposition(DNDC) model to simulate intercropping of maize(Zea mays L.) and soybean(Glycine max L.) and its aftereffect on the succeeding wheat(Triticum aestivum L.) crop was tested in the North China Plain. First, the model was calibrated and corroborated to simulate crop yield and nitrogen(N) uptake based on a field experiment with a typical double cropping system. With a wheat crop in winter, the experiment included five treatments in summer: maize monoculture, soybean monoculture, intercropping of maize and soybean with no N topdressing to maize(N0), intercropping of maize and soybean with 75 kg N ha–1topdressing to maize(N75), and intercropping of maize and soybean with 180 kg N ha–1topdressing to maize(N180). All treatments had 45 kg N ha–1as basal fertilizer. After calibration and corroboration, DNDC was used to simulate long-term(1955 to 2012) treatment effects on yield. Results showed that DNDC could stringently capture the yield and N uptake of the intercropping system under all N management scenarios, though it tended to underestimate wheat yield and N uptake under N0 and N75. Long-term simulation results showed that N75 led to the highest maize and soybean yields per unit planting area among all treatments, increasing maize yield by 59% and soybean yield by 24%, resulting in a land utilization rate 42% higher than monoculture. The results suggest a high potential to promote soybean production by intercropping soybean with maize in the North China Plain, which will help to meet the large national demand for soybean.展开更多
Ecotoxicity and bioavailability of cadmium （Cd） to the maize （Zea mays L.） and the soybean （Glycine max （L.） Merr.） were investigated by acute toxicity experiment in the laboratory with black soil. Ecotoxicity...Ecotoxicity and bioavailability of cadmium （Cd） to the maize （Zea mays L.） and the soybean （Glycine max （L.） Merr.） were investigated by acute toxicity experiment in the laboratory with black soil. Ecotoxicity and bioavailability of Cd were quantified by calculating the median effective concentration （ECs0） and bioaccumulation factor （BAF）. The measurement endpoints used were seed germination and seedling growth （shoot and root）. The results showed that concentrations of Cd in the soil had adverse effect on the growth of roots and shoots. Seed germination was not the sensitive indicator for the ecotoxicity of Cd in the soil, while the growth of roots was the most sensitive measurement endpoint. Absorbability and transport of Cd in plants depended on the test crop species and Cd concentrations in the soil. The maize retains more Cd in its roots, while the soybean transports more Cd to the shoots from roots.展开更多
The practice of intercropping leguminous and gramineous crops is used for promoting sustainable agriculture,optimizing resource utilization,enhancing biodiversity,and reducing reliance on petroleum products.However,pr...The practice of intercropping leguminous and gramineous crops is used for promoting sustainable agriculture,optimizing resource utilization,enhancing biodiversity,and reducing reliance on petroleum products.However,promoting conventional intercropping strategies in modern agriculture can prove challenging.The innovative technology of soybean maize strip intercropping(SMSI)has been proposed as a solution.This system has produced remarkable results in improving domestic soybean and maize production for both food security and sustainable agriculture.In this article,we provide an overview of SMSI and explain how it differs from traditional intercropping.We also discuss the core principles that foster higher yields and the prospects for its future development.展开更多
Maize-soybean relay intercropping is an effective approach to improve the crop yield and nutrient use efficiency,which is widely practiced by farmers in southwest of China.To elucidate the characteristics of different...Maize-soybean relay intercropping is an effective approach to improve the crop yield and nutrient use efficiency,which is widely practiced by farmers in southwest of China.To elucidate the characteristics of different planting patterns on crop nutrient uptake,soil chemical properties,and soil bacteria community in maize-soybean relay intercropping systems,we conducted a field experiment in 2015–2016 with single factor treatments,including monoculture maize(MM),monoculture soybean(MS),maize-soybean relay intercropping(IMS),and fallow(CK).The results showed that the N uptake of maize grain increased in IMS compared with MM.Compared with MS,the yield and uptake of N,P,and K of soybean grain were increased by 25.5,24.4,9.6,and 22.4%in IMS,respectively,while the N and K uptakes in soybean straw were decreased in IMS.The soil total nitrogen,available phosphorus,and soil organic matter contents were significantly higher in IMS than those of the corresponding monocultures and CK.Moreover,the soil protease,soil urease,and soil nitrate reductase activities in IMS were higher than those of the corresponding monocultures and CK.The phyla Proteobacteria,Acidobacteria,Chloroflexi,and Actinobacteria dominated in all treatments.Shannon’s index in IMS was higher than that of the corresponding monocultures and CK.The phylum Proteobacteria proportion was positively correlated with maize soil organic matter and soybean soil total nitrogen content,respectively.These results indicated that the belowground interactions increased the crop nutrient(N and P)uptake and soil bacterial community diversity,both of which contributed to improved soil nutrient management for legume-cereal relay intercropping systems.展开更多
A four-year field experiment was conducted with two cultivars and four N rate to investigate the spatiotemporal characteristics of leaf senescence in maize after silking and its response to N fertilizer rates on them,...A four-year field experiment was conducted with two cultivars and four N rate to investigate the spatiotemporal characteristics of leaf senescence in maize after silking and its response to N fertilizer rates on them,as well as to reveal the differences in post-silking chlorophyll degradation between low-N-tolerant cultivars.The results showed that the order of leaf senescence after silking in maize was lower leaf>upper leaf>ear leaf,leaf tip>middle>base.Increasing N fertilizer down-regulated the expression of ZmCLH2 and ZmPPH in the leaves at 10-30 d after silking,reducing CLH and PPH activities,thereby delaying the leaf senescence.These effects were more prominent in low-N-sensitive cultivar Xianyu 508(XY508)than in low-N-tolerant cultivar Zhenghong 311(ZH311),especially in the lower leaves and leaf tip.Under low N condition,leaf yellowing and chlorophyll degradation occurred later and slower in ZH311 than in XY508.This resulted in a higher post-silking dry matter accumulation and grain yield in ZH311,which may be one of the important physiological bases of low nitrogen tolerant cultivars.Future research should focus on developing low-N-tolerant maize cultivars with slower leaf senescence near the ear after silking.展开更多
Twenty-two field experiments (six maize (Zea mays L.) and five soybean [Glycine max (L.) Merr.] using low glyphosate doses to assess weed control and six maize and five soybean using high glyphosate doses to assess to...Twenty-two field experiments (six maize (Zea mays L.) and five soybean [Glycine max (L.) Merr.] using low glyphosate doses to assess weed control and six maize and five soybean using high glyphosate doses to assess tolerance) were conducted from 2010 to 2012 at two locations in southern Ontario, Canada to compare the commercially available glyphosate formulations of Roundup Weather MAX?, Clearout?41 Plus, and Wise Up? (WeatherMAX, Clearout, and WiseUp, respectively). Inmaize and soybean, control of velvetleaf, pigweed species, common lambs quarters, and green foxtail 4 weeks after treatment (WAT) using 900 g·ae·ha-1 ranged from at least 85% to 99%, regardless of formulation. By 8 WAT with 900 g·ae·ha-1, control of these weeds generally declined, but still ranged from 82% to 97% across all formulations. At harvest, maize yields were similar to the weed-free control for 900 g·ae·ha-1 of glyphosate as WeatherMAX and Clearout;however, reduced weed control with WiseUp resulted in an 8.8% yield loss. For soybean, yields were similar to the weed-free control, regardless of formulation or dose. In the tolerance experiments, 2.1% and 2.8% injury was observed 4 WAT for maize treated with 3600 g·ae·ha-1 of glyphosate as WeatherMAX and WiseUp, respectively. However, maize yields were unaffected by glyphosate formulation or dose. In soybean, visible injury of 8.5%, 4.5%, and 3.7% was observed 1 WAT with 5400 g·ae·ha-1 of glyphosate as WeatherMAX, WiseUp, and Clearout, respectively;by 8 WAT, visible injury was similar to the untreated control, regardless of formulation or dose. The early injury from 5400 g·ae·ha-1 of glyphosate resulted in 8.5%, 4.6%, and 5.5% yield loss for the WeatherMAX, WiseUp, and Clearout formulations, respectively.展开更多
基金supported by National Key Research and Development Program of China(2022YFF1001600)BeijingNatural Science Foundation(5244040)+1 种基金STI2030-Major Projects(2030ZD0407101)China Postdoctoral Science Foundation(2022M723435)。
文摘Drought stress orchestrates a phosphorylation-dependent signaling cascade that reprograms transcriptional networks to enhance crop resilience.Through a large-scale transgenic screening,we identified ZmCRK5A,a Ca^(2+)-independent calcium-dependent protein kinase(CDPK)-related kinase,as a master regulator of drought tolerance in maize.Mechanistically,ZmCRK5A directly phosphorylates the MYB transcriptional repressor ZmSMH4(Single MYB Histone 4)at three conserved serine residues(Ser42/43/59)within its SANT domain,as demonstrated by in vitro kinase assays and site-directed mutagenesis.This post-translational modification abolishes Zm SMH4's DNA-binding capacity to ACC cis-elements,thereby de-repressing the potassium influx channel gene Zm KCH1(K^(+)Channel 1).Functional validation revealed that Zm KCH1 overexpression confers drought resilience through optimized stomatal dynamics and water retention,whereas clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)-generated zmkch1 mutants display hypersensitivity to water deficit.Crucially,field evaluations demonstrated preserved grain yield alongside enhanced drought tolerance in plants with activated Zm CRK5A-Zm SMH4-Zm KCH1 signaling.Our findings delineate a kinase-transcription factor-ion channel axis that dynamically fine-tunes drought responses while maintaining productivity,providing a strategic framework for engineering stress-adapted crops without yield penalties.
基金supported by the University Youth Innovation Science and Technology Support Program of Shandong Province,China(2021KJ073)the Postdoctoral Innovation Program of Shandong Province,China(202003039)+2 种基金the China Agriculture Research System(CARS-02-21)the State Key Laboratory of North China Crop Improvement and Regulation(NCCIR2023KF-8)the Key R&D Program of Shandong Province,China(2023TZXD08603)。
文摘Persistent overcast rain was an essential limiting factor for summer maize production,of which immediate impact was the dual pressure of waterlogging and shading.However,the mechanisms underlying independent and combined effects of waterlogging and shading on maize yield losses remain understudied,particularly across different growth stages.Denghai 605(DH605)was selected to be subjected shading,waterlogging,and their combined stress at the 3rd leaf stage(V3),the 6th leaf stage(V6),and tasseling stage(VT).Results showed that shading,waterlogging and their combination significantly restricted leaf area expansion,reduced leaf net photosynthetic rate(P_(n))and net assimilation rate(NAR),thereby decreasing the crop growth rate(CGR)and biomass accumulation.Additionally,compared to control,the process of lignin synthesis was inhibited under stressed treatment,resulting in diminished stem mechanical strength and impaired vascular system development,which substantially reduced assimilate remobilization efficiency to the ear and ultimate grain yield.Waterlogging and combined stresses exhibited maximum impact at the V3 stage,followed by V6 and VT stages,while shading effects were most pronounced at the VT stage,followed by V6 and V3 stages.Moreover,the compound stress exacerbated the damage brought about by a single stress.As climate change is projected to increase the frequency of multiple abiotic stress occurrences,these findings provide valuable insights for future summer maize breeding research under persistent rainfall conditions.
基金financially supported by the National Natural Science Foundation of China (32071978)the National Key Research and Development Program of China (2022YFD2300901 and 2022YFD2300905)。
文摘High temperature stress (HT) significantly reduces maize yield by impairing starch accumulation in kernels.However,the mechanism by which HT affects starch synthesis remains controversial-whether through reduced assimilate supply or direct inhibition on kernel metabolism.To clarify these mechanisms,a heat-sensitive maize hybrid,Xianyu 335 (XY),was exposed to 30℃/20℃ (maximum/minimum temperature,control) and 40℃/30℃ for seven consecutive days during the seed setting stage.Synchronous pollination (SP),apical pollination (AP),and shading treatments were applied to manipulate the inherent source–sink ratio in maize plants.Results showed that apical kernel weight decreased by 11.9%under 40℃ in the SP treatment.The ^(13)C content,starch accumulation,and cell-wall invertase (CWIN) activity also declined by 15.9,36.7,and 16.4%,respectively,under HT.In the shading treatment,40℃/30℃ caused even greater reductions in^(13)C content,starch accumulation,and CWIN activity due to diminished assimilate supply.Conversely,in the AP treatment,starch content and CWIN activity increased by 22.0 and 18.5%,respectively,under 40℃/30℃,resulting in kernel weight and ^(13)C content similar to those in SP and shading treatments regardless of temperature.Consistent with apical kernels under AP,HT did not negatively affect middle kernels in either SP or shading treatments,as kernel weight and starch content remained unchanged under HT.Although all kernels were exposed to the same HT or control environment,their responses varied a lot.The impaired starch synthesis in apical kernels under HT was rescued by increasing carbon supply via AP treatment.The contrasting performance among middle kernels,apical kernels under AP,and apical kernels under SP or shading indicates that reduced carbon supply is a critical factor underlying inhibited starch accumulation.Our findings provide a theoretical basis for further understanding kernel abortion under HT.
基金supported by the National Key Research and Development Program of China(2021YFF1000504 and 2023YFD1901300)the National Natural Science Foundation of China(32172658,32172659 and 32302662)the Natural Science Foundation of Guangdong Province,China(2021A1515010826).
文摘Maize/soybean intercropping systems are commonly used in developing countries,but few studies have been performed to elucidate the differences in nutrient efficiency and rhizosphere microbiome,especially when maize is intercropped with different soybean varieties.In this study,field experiments were conducted to compare the growth and yield of two soybean(Glycine max)varieties,BD2 and YC03-3,and one maize(Zea mays)variety,Huazhen,in mono-cropped and intercropped cultures.The plant biomass and N content of both crops in BD2/maize intercropping were significantly improved compared to their monoculture,but no such effects were observed in the plants of YC03-3/maize intercropping.The yield of BD2 intercropped with maize exhibited a 37.5%increment above that of BD2 in monoculture.Moreover,19.2-29.1%longer root length of maize and 19.0-39.4%larger root volume of BD2 were observed in BD2/maize intercropping than in monoculture,but no growth advantage was observed in YC03-3/maize intercropping.Maize showed root avoidance when intercropped with BD2,but space competition when intercropped with YC03-3.16S rRNA amplicon sequencing showed that compared with the monoculture system,rhizobacteria community composition in BD2/maize intercropping changed more significantly than that of the YC03-3/maize intercropping system.In BD2/maize intercropping,most of the rhizobacteria community biomarker bacteria of BD2 were positively correlated with plant biomass,as well as plant P and N content.Maize tended to recruit Rhizobiales and Proteobacteria,which showed positive correlation with plant biomass and N content,respectively,as well as soil available N.In conclusion,soybean varieties determined the advantages of maize/soybean intercropping through root-root interactions and modification of rhizobacteria communities.Our insight emphasizes a linkage between root traits and the rhizobacteria community,which shows the importance of optimizing intercropping systems by selection of appropriate crop varieties.
基金supported by grants from the National Natural Science Foundation of China(31771876)the Biological Breeding Program of State Key Laboratory of Sichuan Agricultural University,China(SKL-ZY202234)the Sichuan Province Science and Technology Program,China(2021YFYZ0011 and 2021YFYZ0017)。
文摘Carbohydrate partitioning from source to sink tissues is essential for plant growth and development.However,in maize(Zea mays L.),the molecular mechanisms by which callose synthase genes regulate this process remain largely unexplored.This study demonstrates that mutation of maize callose synthase12(Zm Cals12)results in increased carbohydrate accumulation in photosynthetic leaves but decreased carbohydrate content in sink tissues,leading to plant dwarfing and male sterility.Histochemical β-glucuronidase(GUS)activity assay and m RNA in situ hybridization(ISH)revealed that Zm Cals12 expression mainly occurs in the vascular transport system.Zm Cals12 loss-of-function decreased callose synthase activity and callose deposition in plasmodesmatas(PDs)and surrounding phloem cells(PCs)of the vascular bundle.The drop-and-see(DANS)assay indicated reduced PD permeability in photosynthetic cells and diminished transport competence of leaf veins in Zmcals12 mutants,resulting in decreased symplastic transport.Paraffin section analysis revealed that less-developed vascular cells(VCs)in Zmcals12 mutants likely disrupted sugar transport,contributing to the pleiotropic phenotype.Furthermore,impaired sugar transport inhibited internode development by suppressing auxin(IAA)biosynthesis and signaling in Zmcals12 mutant.These findings elucidate the mechanism by which Zm Cals12-mediated callose deposition and symplastic transport regulate maize growth and development.
基金supported by the Fundamental Research Funds for the Central Universities(N2001020)the National Natural Science Foundation of China(41201359).
文摘Sand dust belts span approximately one-fifth of the global land surface.In these regions,dust tends to settle on vegetation surfaces,altering the observed reflectance and affecting remote sensing detections.To enhance the accuracy of maize growth monitoring in dust-affected regions,this study aims to quantify the effect of sand dust retention on maize during the tasseling stage in the Kashgar Prefecture,Xinjiang Uygur Autonomous Region,China,by analyzing changes in canopy reflectance and vegetation indices.First,field sampling was conducted to measure the key canopy structure parameters and dust retention levels of maize,and laboratory spectral measurements were performed on leaf spectral properties under gradient dust retention.The measured data were then used to drive the LargE-Scale remote sensing data and image Simulation framework(LESS)model for simulating realistic maize canopy spectra across different dust levels,with validation against Sentinel-2 imagery.Second,on the basis of the simulated and satellite-derived spectra,the dust resistance of 36 common vegetation indices was systematically evaluated,and new robust dust-resistant indices were developed.The results showed that compared with dust-free maize,the canopy reflectance of dust-retained maize followed an increase–decrease–increase pattern,with critical turning points at 735 and 1325 nm.The maximum reflectance difference of–0.11755(change rate:29.002%)occurred within the 735–1325 nm range at 24 g/m^(2)dust retention,and the minimum reflectance difference of 0.04285(change rate:148.950%)was observed in the 350–735 nm range under the same dust retention level.Among the 36 vegetation indices,only the global environment monitoring index(GEMI)and the ratio of transformed chlorophyll absorption in reflectance index to optimized soil-adjusted vegetation index(TCARI/OSAVI)exhibited dust resistance,with GEMI being effective below 6 g/m^(2)and TCARI/OSAVI remaining stable across all levels(average ratio:0.970).The newly developed indices in this study,(RE3–RE2)/(NIR–RE2),(RE3–RE2)/(RE4–RE2),and(NIR–RE2)/(RE4–RE2),retained values within the predefined dust-resistant range over the full dust retention levels of 0–24 g/m^(2),thus showing a more stable dust resistance compared with the commonly used 36 vegetation indices.Specially,(RE3–RE2)/(RE4–RE2)performed the most robustly in Sentinel-2 imagery,that is,58.020%of pixels were within the dust-resistant range,and an average ratio of 0.937 was obtained for the original-spectra index.This study provides a scientific basis for crop monitoring and management in dust-affected regions.
基金supported by the earmarked fund for the China Agriculture Research System(CARS-04-PS21)National Key Research and Development Program of China(2024YFD2300401)a recipient of a joint Ph.D.scholarship supported by the China Scholarship Council(CSC)(202306910067)。
文摘The exogenous plant growth regulator,diethyl aminoethyl hexanoate(DA-6),in combination with suitable varieties and planting densities,is important to increase yield in the maize-soybean strip intercropping system.To identify the role of DA-6 in mitigating high-density stress and increasing yield,we conducted a two-year field experiment examining changes in branching architecture and other yield traits of soybeans in maize-soybean strip intercropping systems.In the planting system,two soybean cultivars(ND:Nandou 25 and QH:Qihuang 34)were grown under three planting densities(D1:102,000 plants ha^(-1),D2:130,000 plants ha^(-1),D3:158,000 plants ha^(-1))with DA-6 treatments(DA0:water control;DA60:60 mg L^(-1);DA100:100 mg L^(-1)).Applying DA-6 at 60 mg L^(-1)at the fourth trifoliolate leaf stage increased soybean yield,with QH yield rising by 22.4% and 29.5% at D3 density,and ND yield by 29.5% and 30.0% at D2 density in 2022 and 2023,respectively,compared with D1 under DA0.DA-6improved photosynthesis in both varieties under D2 density,with DA60 increasing ND canopy photosynthetic rate by 15.1%-16.4% and QG by 9.1%-20.6% over two years.In ND,DA-6 enhanced branching,raising the leaf area index by 37%,branch number from 3.6 to 4.7 per plant,and total pod number by 19.7%.In QH,yield grains were mainly due to a 17% increase in the number of stem pods and a 6.5% improvement in hundred-grain weight.In the maize-soybean strip intercropping system,QH achieved a high yield by forming a high-density(D2 to D3)main stem pod,and ND by combining moderate density(D1 to D2)with DA-6-induced branching.
基金China Agriculture Research System of MOF and MARA(CARS-04)National Key Research and Development Program of China(Grant No.2022YFD2300904)the Key Scientific and Technological Project of Henan Province Department of China(Grant No.252102111171).
文摘In view of the existing composite planting cannot do independent control of fertilizer rate for each row,and fertilizer is easy to moisture solidification caking and rely on a single way to measure the speed of inaccurate problems,a split-drive variable fertilizer application system was designed for soybean and maize strip cropping composites.It includes roller crushing bi-directional spiral fertilizer discharger,split-drive variable fertilizer application system and‘GNSS+encoder’dual speed measurement system.By modeling agglomerated fertilizer particles,discrete element simulation was carried out to analyze the crushing effect.The speed measurement error variation folds of both GNSS and encoder under different speed conditions were obtained through field speed measurement tests.Finally,4.5 km/h was identified as the switching point between the two speed measurements.Through bench testing,a mathematical relationship model was developed for the soybean and maize belts in terms of‘Fertilizer Application Rate-Operating Travel Speed-Metering Mechanism Rotor Speed’,and the results are presented in the table below.Fertilizer discharge consistency was verified for fertilizer dischargers.Field trials were conducted,and the results show:The soybean belt had a maximum error of 4.81%at a fertilizer application rate of 150 kg/hm2 and an operating speed of 5 km/h;the maximum error in the corn belt was 4.67%at a fertilizer application rate of 600 kg/hm2 and operating speed of 4 km/h.Both have a maximum error of less than 5%,which meets the requirements for variable fertilizer application.
基金Supported by Natural Science Foundation of Guangxi Province(0236005)Educational Commission of Guangxi Province[(2002)316]~~
文摘[Objective] The experiment was aimed to explore character variation between different families after DNA introduction and select variant plants with good stability. [Method] The method of pollen-tube-pathway was used to introduce total DNA of soybean into normal maize inbred line 7313 for selecting generation by generation. When field characters of maize, grain colors, grain traits and panicle axis colors were stable, the crude protein, gliadin, glutelin and oil content of grains which were selected from variant strains were detected and compared. [Result] The grain crude protein, gliadin, glutelin and oil content of line 26h-4-3 were significantly different from these of control treatment. The increments of D3 and D4 generation were 10.34% and 26.70%, 6.58% and 6.28%, 15.09% and 70.34%, 55.82% and 51.52% respectively. All indexes of line 26h-3-1 were also higher than these of control treatment and the increments of D3 and D4 generation were 5.67% and 21.63%,1.91% and 2.31%, 10.85% and 62.27%,22.49% and 9.67%. [Conclusion] The crude protein, gliadin, glutelin and oil content of variant line 26h-4-3 and 26h-3-1 were stable, so variant line 26h-4-3 and 26h-3-1 were excellent variant strains which satisfied the requirement of high protein breeding.
基金Supported by Special Fund for Agro-scientific Research in the Public Interest(nyhyzx07004-10)Major Science&Technology Program of Sichuan Province(01NG016-01)~~
文摘The effects of different maize sowing dates and densities on stem and leaf morphological characters and yield of soybean in wheat/maize/soybean relaycropping system were studied. The results showed that with early sowing of maize, the maize yield was promoted, and maize was harvested in advance, which reduced the intergrowth period with soybean and guaranteed soybean＇s proper plant height, larger stem diameter and optimal values of LAI and SLW, so that soybean yield was also increased. The effects of different maize densities on the stem and leaf of soybean mainly were significant before the maize harvest, but soybean yield under high maize density was significantly lower than that under middle and low maize density, and the highest maize yield was under middle density. Based on soybean and maize comprehensive values, the optimum combination of this experiment was sowed on March 21 and planting density was 5.25×10^4 plant/hm^2.
基金Supported by the China Agriculture Research System(CARS-09)the Technological Innovation and Industrialization Project for the Rural Area of Nantong City,Jiangsu Province(H12014012)~~
文摘The high-efficiency planting mode for five crops a year of fresh edible ＂faba bean/spring maize＋soybean-autumn maize/autumn soybean＂ was introduced, and its yield and economic benefits were compared with the planting mode of three crops a year of ＂faba bean-spring maize/red bean＂. The results showed that the planting method for fresh edible ＂faba bean/spring maize＋soybean-autumn maize/autumn soybean＂ was much easier to operate with the input-output ratio of about185.6%, and its yield and economic benefits were 2.09 and 1.83 times of that of the planting mode for three crops a year, significantly improving the agricultural yield and income of farmers. In addition, the cropping index of the planting mode for fresh edible fresh edible ＂faba bean/spring maize ＋soybean-autumn maize/autumn soybean＂ reached up to 350%, and planting faba bean once a year and soybean twice a year could make the biological fixation amount of nitrogen increase 350-450kg/m^2, which equaled to up to 700 kg/m^2 of urea, showing significant ecological and social benefits. Based on the comparison results, the high-yield culture techniques of the planting mode of fresh edible ＂faba bean/spring maize＋soybean-autumn maize/autumn soybean＂ were summarized.
文摘Intercropping, particularly the combination of maize and soybeans, has been widely recognized for its potential to improve nitrogen uptake and promote sustainable agriculture. This study examines the patterns of nitrogen uptake in maize and soybean intercropping systems under different growth stages and phosphorus fertilization levels and investigates the influence of nitrogen uptake on growth parameters such as plant height, leaf area, and biomass accumulation in the maize/soybean intercrop under different phosphorus fertilization regimes. The study also collected chlorophyll samples at different growth stages of maize in monoculture and intercropping with maize or soybean. The results showed that plant height was greater in V10 in both fertilized and unfertilized treatments for intercropped maize and soybean, and chlorophyll concentration was higher in VT intercropped maize. The results also showed a higher accumulation of biomass. Understanding the growth dynamics of these plants in monoculture and intercropping systems and the impact of fertilization practices is crucial for optimizing crop productivity and sustainability in agricultural systems.
基金Supported by the National Transformation Project for Agriculture Science and Technology Achievements(2011GB2C300011)the National Science and Technology Funds for Agriculture during the Twelfth Five-year Plan(2011BAD35B06-4)~~
文摘[Objective] The aim was to discuss the group dry matter accumulation and economic benefits under the patterns of intercropping maize （Zea mays L.） with soy-bean [Glycine max （L.） Merril ]. [Methods] Zhengdan-958 and Luhuang-1 were used as the testing breeds to study the effects of intercropping patterns on dry matter accumulation and transportation of maize and soybean in Huang-huai-hai. [Results] For maize, the dry matter accumulation amounts per hectare of intercropping was significant higher than that of the monoculture patterns, especial y after silking, when it reached extremely level; while for soybean, the dry matter accumulation amounts before flowering and after flowering of monocropping were al significantly higher than that of the intercropping patterns. For both maize and soybean, the transfer amounts of monocropping were al significantly or extremely significantly higher than that of intercropping; and the transfer ratio of maize intercropping was 0.59% higher than that of maize monocropping, while for soybean, it was 4.74% higher. Fitted dry matter accumulation with Logistic equation, it showed that the difference in maximum dry matter accumulation rate between maize monocropping and intercropping reached significant level, while for soybean, the maximum dry matter accumulation rate and its appearance time as wel as duration time between intercropping and monocropping were al reached significant level. The total land equivalent ratio of intercropping was 1.30. From yield and output value, the total yield of intercropping were 10.97 t/hm2, 0.64% and 326.85% higher than monocropping of maize and soy-bean, respectively. The total output value of intercropping was 25 796.23 yuan/hm2, respectively 12.67% and 104.68% higher than of maize and soybean monocropping. [Conclusion] The study lays a basis for improving grain yield and economic benefits.
基金supported by the National Natural Science Foundation of China (31401308, 31371555 and 31671445)
文摘Intercropping is one of the most vital practice to improve land utilization rate in China that has limited arable land resource. However, the traditional intercropping systems have many disadvantages including illogical field lay-out of crops, low economic value, and labor deficiency, which cannot balance the crop production and agricultural sustainability. In view of this, we developed a novel soybean strip intercropping model using maize as the partner, the regular maize-soybean strip intercropping mainly popularized in northern China and maize-soybean relay-strip intercropping principally extended in southwestern China. Compared to the traditional maize-soybean intercropping systems, the main innovation of field lay-out style in our present intercropping systems is that the distance of two adjacent maize rows are shrunk as a narrow strip, and a strip called wide strip between two adjacent narrow strips is expanded reserving for the growth of two or three rows of soybean plants. The distance between outer rows of maize and soybean strips are expanded enough for light use efficiency improvement and tractors working in the soybean strips. Importantly, optimal cultivar screening and increase of plant density achieved a high yield of both the two crops in the intercropping systems and increased land equivalent ratio as high as 2.2. Annually alternative rotation of the adjacent maize-and soybean-strips increased the grain yield of next seasonal maize, improved the absorption of nitrogen, phosphorus, and potasium of maize, while prevented the continuous cropping obstacles. Extra soybean production was obtained without affecting maize yield in our strip intercropping systems, which balanced the high crop production and agricultural sustainability.
基金supported by the National Natural Science Foundation of China (31701995 and 31572208)the National Key Research & Development Program of China (2016YFD0800101)+1 种基金the Newton Fund of UK-China (BB/N013484/1)supported by China Scholarship Council (2015-7169)
文摘Intercropping is an important agronomic practice. However, assessment of intercropping systems using field experiments is often limited by time and cost. In this study, the suitability of using the DeNitrification DeComposition(DNDC) model to simulate intercropping of maize(Zea mays L.) and soybean(Glycine max L.) and its aftereffect on the succeeding wheat(Triticum aestivum L.) crop was tested in the North China Plain. First, the model was calibrated and corroborated to simulate crop yield and nitrogen(N) uptake based on a field experiment with a typical double cropping system. With a wheat crop in winter, the experiment included five treatments in summer: maize monoculture, soybean monoculture, intercropping of maize and soybean with no N topdressing to maize(N0), intercropping of maize and soybean with 75 kg N ha–1topdressing to maize(N75), and intercropping of maize and soybean with 180 kg N ha–1topdressing to maize(N180). All treatments had 45 kg N ha–1as basal fertilizer. After calibration and corroboration, DNDC was used to simulate long-term(1955 to 2012) treatment effects on yield. Results showed that DNDC could stringently capture the yield and N uptake of the intercropping system under all N management scenarios, though it tended to underestimate wheat yield and N uptake under N0 and N75. Long-term simulation results showed that N75 led to the highest maize and soybean yields per unit planting area among all treatments, increasing maize yield by 59% and soybean yield by 24%, resulting in a land utilization rate 42% higher than monoculture. The results suggest a high potential to promote soybean production by intercropping soybean with maize in the North China Plain, which will help to meet the large national demand for soybean.
基金Under the auspices of the Key Innovation Program of Chinese Academy of Sciences(No.KZCX1-SW-19-4-01)the National Key Basic Research and Development Program of China(No.2004CB41850407)
文摘Ecotoxicity and bioavailability of cadmium （Cd） to the maize （Zea mays L.） and the soybean （Glycine max （L.） Merr.） were investigated by acute toxicity experiment in the laboratory with black soil. Ecotoxicity and bioavailability of Cd were quantified by calculating the median effective concentration （ECs0） and bioaccumulation factor （BAF）. The measurement endpoints used were seed germination and seedling growth （shoot and root）. The results showed that concentrations of Cd in the soil had adverse effect on the growth of roots and shoots. Seed germination was not the sensitive indicator for the ecotoxicity of Cd in the soil, while the growth of roots was the most sensitive measurement endpoint. Absorbability and transport of Cd in plants depended on the test crop species and Cd concentrations in the soil. The maize retains more Cd in its roots, while the soybean transports more Cd to the shoots from roots.
基金supported by the National Natural Science Foundation of China(31971853)。
文摘The practice of intercropping leguminous and gramineous crops is used for promoting sustainable agriculture,optimizing resource utilization,enhancing biodiversity,and reducing reliance on petroleum products.However,promoting conventional intercropping strategies in modern agriculture can prove challenging.The innovative technology of soybean maize strip intercropping(SMSI)has been proposed as a solution.This system has produced remarkable results in improving domestic soybean and maize production for both food security and sustainable agriculture.In this article,we provide an overview of SMSI and explain how it differs from traditional intercropping.We also discuss the core principles that foster higher yields and the prospects for its future development.
基金supported by the National Natural Science Foundation of China (31671625, 31271669)the National Key Research and Development Program of China (2016YFD0300202)
文摘Maize-soybean relay intercropping is an effective approach to improve the crop yield and nutrient use efficiency,which is widely practiced by farmers in southwest of China.To elucidate the characteristics of different planting patterns on crop nutrient uptake,soil chemical properties,and soil bacteria community in maize-soybean relay intercropping systems,we conducted a field experiment in 2015–2016 with single factor treatments,including monoculture maize(MM),monoculture soybean(MS),maize-soybean relay intercropping(IMS),and fallow(CK).The results showed that the N uptake of maize grain increased in IMS compared with MM.Compared with MS,the yield and uptake of N,P,and K of soybean grain were increased by 25.5,24.4,9.6,and 22.4%in IMS,respectively,while the N and K uptakes in soybean straw were decreased in IMS.The soil total nitrogen,available phosphorus,and soil organic matter contents were significantly higher in IMS than those of the corresponding monocultures and CK.Moreover,the soil protease,soil urease,and soil nitrate reductase activities in IMS were higher than those of the corresponding monocultures and CK.The phyla Proteobacteria,Acidobacteria,Chloroflexi,and Actinobacteria dominated in all treatments.Shannon’s index in IMS was higher than that of the corresponding monocultures and CK.The phylum Proteobacteria proportion was positively correlated with maize soil organic matter and soybean soil total nitrogen content,respectively.These results indicated that the belowground interactions increased the crop nutrient(N and P)uptake and soil bacterial community diversity,both of which contributed to improved soil nutrient management for legume-cereal relay intercropping systems.
基金supported by the National Key Research and Development Program of China(2022YFD190160304 and 2018YFD0301206)Natural Science Foundation of Sichuan Province(2022NSFSC0013)Sichuan Provincial Maize Innovation Team Construction Project(SCCXTD-2023-02).
文摘A four-year field experiment was conducted with two cultivars and four N rate to investigate the spatiotemporal characteristics of leaf senescence in maize after silking and its response to N fertilizer rates on them,as well as to reveal the differences in post-silking chlorophyll degradation between low-N-tolerant cultivars.The results showed that the order of leaf senescence after silking in maize was lower leaf>upper leaf>ear leaf,leaf tip>middle>base.Increasing N fertilizer down-regulated the expression of ZmCLH2 and ZmPPH in the leaves at 10-30 d after silking,reducing CLH and PPH activities,thereby delaying the leaf senescence.These effects were more prominent in low-N-sensitive cultivar Xianyu 508(XY508)than in low-N-tolerant cultivar Zhenghong 311(ZH311),especially in the lower leaves and leaf tip.Under low N condition,leaf yellowing and chlorophyll degradation occurred later and slower in ZH311 than in XY508.This resulted in a higher post-silking dry matter accumulation and grain yield in ZH311,which may be one of the important physiological bases of low nitrogen tolerant cultivars.Future research should focus on developing low-N-tolerant maize cultivars with slower leaf senescence near the ear after silking.
文摘Twenty-two field experiments (six maize (Zea mays L.) and five soybean [Glycine max (L.) Merr.] using low glyphosate doses to assess weed control and six maize and five soybean using high glyphosate doses to assess tolerance) were conducted from 2010 to 2012 at two locations in southern Ontario, Canada to compare the commercially available glyphosate formulations of Roundup Weather MAX?, Clearout?41 Plus, and Wise Up? (WeatherMAX, Clearout, and WiseUp, respectively). Inmaize and soybean, control of velvetleaf, pigweed species, common lambs quarters, and green foxtail 4 weeks after treatment (WAT) using 900 g·ae·ha-1 ranged from at least 85% to 99%, regardless of formulation. By 8 WAT with 900 g·ae·ha-1, control of these weeds generally declined, but still ranged from 82% to 97% across all formulations. At harvest, maize yields were similar to the weed-free control for 900 g·ae·ha-1 of glyphosate as WeatherMAX and Clearout;however, reduced weed control with WiseUp resulted in an 8.8% yield loss. For soybean, yields were similar to the weed-free control, regardless of formulation or dose. In the tolerance experiments, 2.1% and 2.8% injury was observed 4 WAT for maize treated with 3600 g·ae·ha-1 of glyphosate as WeatherMAX and WiseUp, respectively. However, maize yields were unaffected by glyphosate formulation or dose. In soybean, visible injury of 8.5%, 4.5%, and 3.7% was observed 1 WAT with 5400 g·ae·ha-1 of glyphosate as WeatherMAX, WiseUp, and Clearout, respectively;by 8 WAT, visible injury was similar to the untreated control, regardless of formulation or dose. The early injury from 5400 g·ae·ha-1 of glyphosate resulted in 8.5%, 4.6%, and 5.5% yield loss for the WeatherMAX, WiseUp, and Clearout formulations, respectively.
