Flavonoids produced by legume roots act as signaling molecules that induce the expression of nod genes in symbiotic rhizobia.However,the role of flavonoids in root exudates under intercropping systems in promoting soy...Flavonoids produced by legume roots act as signaling molecules that induce the expression of nod genes in symbiotic rhizobia.However,the role of flavonoids in root exudates under intercropping systems in promoting soybean nodulation remains unclear.Two consecutive years of field experiments were conducted using maize–soybean strip intercropping with interspecific row spacings of 30 cm(MS30),45 cm(MS45),and 60 cm(MS60),along with sole cropping of soybean(SS)and maize(MM).Root interactions were manipulated using either no root barrier(NB)or a polyethylene plastic barrier(PB)to assess the relationship between flavonoids in root exudates and soybean nodulation.We found that root–root interaction between soybean and maize increased nodule number and fresh weight in intercropped soybean,with enhancement gradually increasing as interspecific distance widened.The proportion of nodules with diameters exceeding 0.4 cm was higher in intercropped soybean under NB compared to PB.Additionally,the expression of nodule-related genes-GmENOD40,Gm NIN2b,and Gm EXPB2-was up-regulated.Furthermore,compared to monocropping,isoflavone secretion by soybean roots decreased,whereas flavonoid and flavonol secretion by both maize and soybean roots increased under intercropping.The abundance of differentially secreted flavonoid metabolites in the rhizosphere of both species declined when root contact was prevented by the barrier.In soybean roots,the expression of Gm CHS8 and Gm IFS1 was up-regulated,while Gm ICHG was down-regulated under root interaction.Most flavonoid and flavonol compounds showed positive correlations with nodule diameter.Nodule number,fresh weight,and the proportion of nodules larger than 0.2 cm increased in diverse soybean genotypes treated with maize root exudates,which contributed to enhanced nitrogen fixation capacity.Therefore,maize–soybean strip intercropping,combined with optimal row spacing,enhances the positive effects of underground root interactions and improves nodulation and nitrogen fixation in intercropped soybean.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
[Objectives]This study was conducted to investigate the impact of soybean intercropping on soil fertility in the planting areas of high-quality peach orchards in Shenxi Town,Zunyi City,Guizhou Province.[Methods]Soil s...[Objectives]This study was conducted to investigate the impact of soybean intercropping on soil fertility in the planting areas of high-quality peach orchards in Shenxi Town,Zunyi City,Guizhou Province.[Methods]Soil samples were collected during the seedling,growth,and maturity stages of soybeans from both non-intercropped soil(control check group,CK)and soybean-intercropped soil(Qiandou 11,experimental group,EK).Analysis was conducted on soil fertility properties,including alkali-hydrolyzable N,available P,and available K.[Results]The impact of soybean intercropping on soil physicochemical properties was primarily manifested as the increased levels of alkali-hydrolyzable N and available K and the decreased level of available P in the soil during the seedling,growing,and maturity stages.Overall,this approach optimized and enhanced soil fertility in the peach orchards,providing a viable pathway for soil improvement in peach orchards located in karst areas.[Conclusions]The findings of this study provide a scientific basis for the high-quality development of high-quality peach orchards.展开更多
[Objectives]To identify the optimal combination of herbicide concentrations appropriate for soil closed weeding in the soybean and corn intercropping system in Zhongwei City.[Methods]Two herbicides,96%(S)-metolachlor ...[Objectives]To identify the optimal combination of herbicide concentrations appropriate for soil closed weeding in the soybean and corn intercropping system in Zhongwei City.[Methods]Two herbicides,96%(S)-metolachlor and 75%thifensulfuron methyl,were selected for this experiment.A no-herbicide treatment served as the control,and five concentration gradients of the herbicides were established.Prior to sowing,the soil underwent a closed weeding treatment.The impacts of various herbicide concentration combinations on growth indicators,weed control effect,and the yields of soybean and corn across various treatments were analyzed.[Results]The tested combinations of herbicide concentrations did not result in significant phytotoxicity to soybean and corn seedlings.Furthermore,as the herbicide concentrations increased in each treatment,treatments D and E demonstrated the most effective weed control effect.Specifically,40 d post application,the plant control effect and fresh weight control effect reached 97.25% and 98.03% for treatment D,and 97.25% and 98.24% for treatment E,respectively.Additionally,the yields of both soybean and corn showed significant increases.[Conclusions]Considering the overall output-input ratio in this region,treatment D,comprising 96%(S)-metolachlor at 1650 mL/hm^(2) and 75% thifensulfuron-methyl at 48 g/hm^(2),can be identified as the herbicide concentration combination that provides the most effective weed control effect in the soybean and corn strip intercropping system.展开更多
The research mainly analyzed effects of waxy corn/soybean intercropping on yields of the two crops, as well as agronomic characters, and the economic benefits of the mode. The results showed that although yields of wa...The research mainly analyzed effects of waxy corn/soybean intercropping on yields of the two crops, as well as agronomic characters, and the economic benefits of the mode. The results showed that although yields of waxy corn and soybean went down by 21.19% and 31.04% per unit area, land equivalent ratio（1.48） kept higher than 1, suggesting the intercropping improves land use rate. Besides, due to the practice of intercropping, many characters of waxy corn grew, but of soybean declined. The economic benefits from high to low were waxy corn/soybean intercropping, monoculture of waxy corn, and monoculture of soybean.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
The intercropping system of tree with soybean in juvenile plantations, as a short-term practice, was applied at Lao Shan Experimental Station in Mao＇er Shan Forest of Northeast Forestry University, Harbin, China. The...The intercropping system of tree with soybean in juvenile plantations, as a short-term practice, was applied at Lao Shan Experimental Station in Mao＇er Shan Forest of Northeast Forestry University, Harbin, China. The larch （Larix gmelinii）lsoybean （Glycine max.） and ash （Fraxinus mandshurica） intercropping systems were studied in the field to assess the effects of the intercropping on soil physicochemical properties. The results showed that soil physical properties were improved after soybean intercropping with larch and ash in one growing season. The soil bulk density in larch/soybean and ash/soybean systems was 1.112 g·cm^-3 and 1.058 g·cm^ 3, respectively, which was lower than that in the pure larch or ash plantation without intercropping. The total soil porosity also increased after intercropping. The organic matter amount in larch/soybean system was 1.77 times higher than that in the pure larch plantation, and it was 1.09 times higher in ash/soybean system than that in the pure ash plantation. Contents of total nitrogen and hydrolyzable nitrogen in larch/soybean system were 4.2% and 53.0% higher than those in the pure larch stand. Total nitrogen and hydrolyzable nitrogen contents in ash/soybean system were 75.5% and 3.3% higher than those in the pure ash plantation. Total phosphorus content decreased after intercropping, while change of available phosphorus showed an increasing trend. Total potassium and available potassium contents in the larch/soybean system were 0.6% and 17.5% higher than those in the pure larch stand. Total potassium and available potassium contents in the ash/soybean system were 56.4% and 21.8% higher than those in the oure ash plantation.展开更多
Sugarcane/soybean intercropping with reduced nitrogen addition is an important sustainable agricultural pattern that can alter soil ecological functions,thereby affecting straw decomposition in the soil.However,the me...Sugarcane/soybean intercropping with reduced nitrogen addition is an important sustainable agricultural pattern that can alter soil ecological functions,thereby affecting straw decomposition in the soil.However,the mechanisms underlying changes in soil organic carbon(SOC)composition and microbial communities during straw decomposition under long-term intercropping with reduced nitrogen addition remain unclear.In this study,we conducted an in-situ microplot incubation experiment with^(13)C-labeled soybean straw residue addition in a two-factor(cropping pattern:sugarcane monoculture(MS)and sugarcane/soybean intercropping(SB);nitrogen addition levels:reduced nitrogen addition(N1)and conventional nitrogen addition(N2))long-term experimental field plot.The results showed that the SBN1 treatment significantly increased the residual particulate organic carbon(POC)and residual microbial biomass carbon(MBC)contents during straw decomposition,and the straw carbon in soil was mainly conserved as POC.Straw addition changed the structure and reduced the diversity of the soil microbial community,but microbial diversity gradually recovered with decomposition time.During straw decomposition,the intercropping pattern significantly increased the relative abundances of Firmicutes and Ascomycota.In addition,straw addition reduced microbial network complexity in the sugarcane/soybean intercropping pattern but increased it in the sugarcane monoculture pattern.Nevertheless,microbial network complexity remained higher in the SBN1 treatment than in the MSN1 treatment.In general,the SBN1 treatment significantly increased the diversity of microbial communities and the relative abundance of microorganisms associated with organic matter decomposition,and the changes in microbial communities were mainly driven by the residual labile SOC fractions.These findings suggest that more straw carbon can be sequestered in the soil under sugarcane/soybean intercropping with reduced nitrogen addition to maintain microbial diversity and contribute to the development of sustainable agriculture.展开更多
基金funded by the National Key Research and Development Program of China(2021YFF1000500)the National Natural Science Foundation of China(32372231)(3187101212)the earmarked fund for China Agriculture Research System(CARS-04-PS21)。
文摘Flavonoids produced by legume roots act as signaling molecules that induce the expression of nod genes in symbiotic rhizobia.However,the role of flavonoids in root exudates under intercropping systems in promoting soybean nodulation remains unclear.Two consecutive years of field experiments were conducted using maize–soybean strip intercropping with interspecific row spacings of 30 cm(MS30),45 cm(MS45),and 60 cm(MS60),along with sole cropping of soybean(SS)and maize(MM).Root interactions were manipulated using either no root barrier(NB)or a polyethylene plastic barrier(PB)to assess the relationship between flavonoids in root exudates and soybean nodulation.We found that root–root interaction between soybean and maize increased nodule number and fresh weight in intercropped soybean,with enhancement gradually increasing as interspecific distance widened.The proportion of nodules with diameters exceeding 0.4 cm was higher in intercropped soybean under NB compared to PB.Additionally,the expression of nodule-related genes-GmENOD40,Gm NIN2b,and Gm EXPB2-was up-regulated.Furthermore,compared to monocropping,isoflavone secretion by soybean roots decreased,whereas flavonoid and flavonol secretion by both maize and soybean roots increased under intercropping.The abundance of differentially secreted flavonoid metabolites in the rhizosphere of both species declined when root contact was prevented by the barrier.In soybean roots,the expression of Gm CHS8 and Gm IFS1 was up-regulated,while Gm ICHG was down-regulated under root interaction.Most flavonoid and flavonol compounds showed positive correlations with nodule diameter.Nodule number,fresh weight,and the proportion of nodules larger than 0.2 cm increased in diverse soybean genotypes treated with maize root exudates,which contributed to enhanced nitrogen fixation capacity.Therefore,maize–soybean strip intercropping,combined with optimal row spacing,enhances the positive effects of underground root interactions and improves nodulation and nitrogen fixation in intercropped soybean.
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 Undergraduate Innovation and Entrepreneurship Training Program of Guizhou Province(S2024106642161)Zunyi City and Zunyi Normal University Joint Technology Research Fund(ZSKH HZ Z(2023)159)+3 种基金Zunyi Science and Technology Support Program Project(ZSKHZC NS[2023]15)Science and Technology Commissioner Innovation and Entrepreneurship Service Training Demonstration Base of Guizhou Province(HHG2025001)Natural Science Research Project of Department of Education of Guizhou Province(QJJ[2023]043)Zunyi Science and Technology Innovation Team Project(ZKCTD008).
文摘[Objectives]This study was conducted to investigate the impact of soybean intercropping on soil fertility in the planting areas of high-quality peach orchards in Shenxi Town,Zunyi City,Guizhou Province.[Methods]Soil samples were collected during the seedling,growth,and maturity stages of soybeans from both non-intercropped soil(control check group,CK)and soybean-intercropped soil(Qiandou 11,experimental group,EK).Analysis was conducted on soil fertility properties,including alkali-hydrolyzable N,available P,and available K.[Results]The impact of soybean intercropping on soil physicochemical properties was primarily manifested as the increased levels of alkali-hydrolyzable N and available K and the decreased level of available P in the soil during the seedling,growing,and maturity stages.Overall,this approach optimized and enhanced soil fertility in the peach orchards,providing a viable pathway for soil improvement in peach orchards located in karst areas.[Conclusions]The findings of this study provide a scientific basis for the high-quality development of high-quality peach orchards.
基金Supported by 2024-2025 Science and Technology Plan Project of Zhongwei City in the Field of Agriculture,Rural Areas and Social Development"Precision Fertilization Trial Study for Soybean and Corn Strip Intercropping in 2025"(2024nync006)"Smart Innovation for the Future"Talent Cultivation Project of Zhongwei City(WDRCB[2023]6).
文摘[Objectives]To identify the optimal combination of herbicide concentrations appropriate for soil closed weeding in the soybean and corn intercropping system in Zhongwei City.[Methods]Two herbicides,96%(S)-metolachlor and 75%thifensulfuron methyl,were selected for this experiment.A no-herbicide treatment served as the control,and five concentration gradients of the herbicides were established.Prior to sowing,the soil underwent a closed weeding treatment.The impacts of various herbicide concentration combinations on growth indicators,weed control effect,and the yields of soybean and corn across various treatments were analyzed.[Results]The tested combinations of herbicide concentrations did not result in significant phytotoxicity to soybean and corn seedlings.Furthermore,as the herbicide concentrations increased in each treatment,treatments D and E demonstrated the most effective weed control effect.Specifically,40 d post application,the plant control effect and fresh weight control effect reached 97.25% and 98.03% for treatment D,and 97.25% and 98.24% for treatment E,respectively.Additionally,the yields of both soybean and corn showed significant increases.[Conclusions]Considering the overall output-input ratio in this region,treatment D,comprising 96%(S)-metolachlor at 1650 mL/hm^(2) and 75% thifensulfuron-methyl at 48 g/hm^(2),can be identified as the herbicide concentration combination that provides the most effective weed control effect in the soybean and corn strip intercropping system.
基金Supported by Double-establishment of Chengdu Cereals and Commercial Crop Industries in 2014~~
文摘The research mainly analyzed effects of waxy corn/soybean intercropping on yields of the two crops, as well as agronomic characters, and the economic benefits of the mode. The results showed that although yields of waxy corn and soybean went down by 21.19% and 31.04% per unit area, land equivalent ratio（1.48） kept higher than 1, suggesting the intercropping improves land use rate. Besides, due to the practice of intercropping, many characters of waxy corn grew, but of soybean declined. The economic benefits from high to low were waxy corn/soybean intercropping, monoculture of waxy corn, and monoculture of soybean.
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.
文摘The intercropping system of tree with soybean in juvenile plantations, as a short-term practice, was applied at Lao Shan Experimental Station in Mao＇er Shan Forest of Northeast Forestry University, Harbin, China. The larch （Larix gmelinii）lsoybean （Glycine max.） and ash （Fraxinus mandshurica） intercropping systems were studied in the field to assess the effects of the intercropping on soil physicochemical properties. The results showed that soil physical properties were improved after soybean intercropping with larch and ash in one growing season. The soil bulk density in larch/soybean and ash/soybean systems was 1.112 g·cm^-3 and 1.058 g·cm^ 3, respectively, which was lower than that in the pure larch or ash plantation without intercropping. The total soil porosity also increased after intercropping. The organic matter amount in larch/soybean system was 1.77 times higher than that in the pure larch plantation, and it was 1.09 times higher in ash/soybean system than that in the pure ash plantation. Contents of total nitrogen and hydrolyzable nitrogen in larch/soybean system were 4.2% and 53.0% higher than those in the pure larch stand. Total nitrogen and hydrolyzable nitrogen contents in ash/soybean system were 75.5% and 3.3% higher than those in the pure ash plantation. Total phosphorus content decreased after intercropping, while change of available phosphorus showed an increasing trend. Total potassium and available potassium contents in the larch/soybean system were 0.6% and 17.5% higher than those in the pure larch stand. Total potassium and available potassium contents in the ash/soybean system were 56.4% and 21.8% higher than those in the oure ash plantation.
基金supported by the China National Key R&D Program during the 14th Five-year Plan Period(2022YFD1901603)。
文摘Sugarcane/soybean intercropping with reduced nitrogen addition is an important sustainable agricultural pattern that can alter soil ecological functions,thereby affecting straw decomposition in the soil.However,the mechanisms underlying changes in soil organic carbon(SOC)composition and microbial communities during straw decomposition under long-term intercropping with reduced nitrogen addition remain unclear.In this study,we conducted an in-situ microplot incubation experiment with^(13)C-labeled soybean straw residue addition in a two-factor(cropping pattern:sugarcane monoculture(MS)and sugarcane/soybean intercropping(SB);nitrogen addition levels:reduced nitrogen addition(N1)and conventional nitrogen addition(N2))long-term experimental field plot.The results showed that the SBN1 treatment significantly increased the residual particulate organic carbon(POC)and residual microbial biomass carbon(MBC)contents during straw decomposition,and the straw carbon in soil was mainly conserved as POC.Straw addition changed the structure and reduced the diversity of the soil microbial community,but microbial diversity gradually recovered with decomposition time.During straw decomposition,the intercropping pattern significantly increased the relative abundances of Firmicutes and Ascomycota.In addition,straw addition reduced microbial network complexity in the sugarcane/soybean intercropping pattern but increased it in the sugarcane monoculture pattern.Nevertheless,microbial network complexity remained higher in the SBN1 treatment than in the MSN1 treatment.In general,the SBN1 treatment significantly increased the diversity of microbial communities and the relative abundance of microorganisms associated with organic matter decomposition,and the changes in microbial communities were mainly driven by the residual labile SOC fractions.These findings suggest that more straw carbon can be sequestered in the soil under sugarcane/soybean intercropping with reduced nitrogen addition to maintain microbial diversity and contribute to the development of sustainable agriculture.
