Relay cropping of Poaceae and Fabaceae promotes high yield and land-use efficiency by allowing a double harvest.However,it is difficult to increase yield synergistically because of the reduced photosynthetic abilities...Relay cropping of Poaceae and Fabaceae promotes high yield and land-use efficiency by allowing a double harvest.However,it is difficult to increase yield synergistically because of the reduced photosynthetic abilities of legume leaves under the shade of graminoids.Leaf photosynthetic capacity in relay cropping systems is associated with ecological niche differentiation and photosynthetic compensation after restoration of normal light.We conducted a field experiment in southwest China in 2020–2021 to evaluate the effects of three cropping patterns:maize–soybean relay cropping(IMS),monoculture maize(MM),and monoculture soybean(SS),and N application levels:no N application(NN:0 kg N ha^(−1)),reduced N(RN:180 kg N ha^(−1)),and conventional N(CN:240 kg N ha^(−1)).Compared to monocropping,relay cropping increased the stay-green traits of maize and soybean by 13%and 89%,respectively.Relay cropping prolonged the leaf stay-green duration in the maize and soybean lag phase by almost 4 and 8 days,respectively.Relay cropping maize(IM)increased the leaf area index(LAI)by 79.4%to 88.5%under NN and 55.5%to 148%under RN.Relay cropping soybean(IS)increased the LAI from 115%to 437%at days 40 to 50 after anthesis.IM increased yield by 65.6%.IS increased yield by 9.7%.HI and system yield were at their highest values under RN.In the relay cropping system,reduced N application extended green leaf duration,increased photosynthesis inside the canopy at multiple levels,ultimately increases soybean yield synergistically.展开更多
Sustainable intensification of cropping systems is a strategy to increase productivity and reduce disservices of conventional agroecosystems.Camelina[Camelina sativa(L.)Crantz]and field pennycress(Thlaspi arvense L.)a...Sustainable intensification of cropping systems is a strategy to increase productivity and reduce disservices of conventional agroecosystems.Camelina[Camelina sativa(L.)Crantz]and field pennycress(Thlaspi arvense L.)are winter annual oilseed crops well suited to fill the fallow period between corn(Zea mays L.)and soybean[Glycine max(L.)Merr.]in the U.S.northern Corn Belt,but their inclusion may be limited by resource use limitations.A 2-year study was conducted from 2015 to 2017 in the U.S.upper Midwest to evaluate the effect of double cropping on winter oilseed crops and soybean productivity and economic performance.Treatments included relay-and sequential-cropped soybean with winter camelina and field pennycress,and monocrop soybean as control.Biomass and grain yield of winter oilseed crops were not affected by cropping system.Averaged over years and cropping systems,winter camelina resulted in more biomass,nitrogen(N)uptake and grain yield by 240,186 and 139% respectively,compared to field pennycress.Soybean biomass,N uptake and yield were higher in relay relative to sequential cropping.Relay soybean resulted in similar total grain yield(soybean+winter oilseed crop)compared to monocropped soybean.Double cropping soybean could maintain net return compared to monocropped soybean.Results indicate that double cropping winter oilseed crops with soybean can be economically viable in the U.S.upper Midwest.Yet,research aimed at optimizing yield through N and water use while improving ecosystem services is needed.展开更多
基金the Special Fund for the Industrial Technology System Construction of Modem Agriculture(CARS-04-PS20)the National Natural Science Foundation of China(31872856,31671625)the National Key Research and Development Program of China(2021YFF1000500)。
文摘Relay cropping of Poaceae and Fabaceae promotes high yield and land-use efficiency by allowing a double harvest.However,it is difficult to increase yield synergistically because of the reduced photosynthetic abilities of legume leaves under the shade of graminoids.Leaf photosynthetic capacity in relay cropping systems is associated with ecological niche differentiation and photosynthetic compensation after restoration of normal light.We conducted a field experiment in southwest China in 2020–2021 to evaluate the effects of three cropping patterns:maize–soybean relay cropping(IMS),monoculture maize(MM),and monoculture soybean(SS),and N application levels:no N application(NN:0 kg N ha^(−1)),reduced N(RN:180 kg N ha^(−1)),and conventional N(CN:240 kg N ha^(−1)).Compared to monocropping,relay cropping increased the stay-green traits of maize and soybean by 13%and 89%,respectively.Relay cropping prolonged the leaf stay-green duration in the maize and soybean lag phase by almost 4 and 8 days,respectively.Relay cropping maize(IM)increased the leaf area index(LAI)by 79.4%to 88.5%under NN and 55.5%to 148%under RN.Relay cropping soybean(IS)increased the LAI from 115%to 437%at days 40 to 50 after anthesis.IM increased yield by 65.6%.IS increased yield by 9.7%.HI and system yield were at their highest values under RN.In the relay cropping system,reduced N application extended green leaf duration,increased photosynthesis inside the canopy at multiple levels,ultimately increases soybean yield synergistically.
基金the support of the Minnesota Soybean Research&Promotion Council(Grant No.819717)Shanxi Province Key Laboratory of Soil Environment and Nutrient Resources(Grant No.2019002)National Natural Science Foundation of China(Grant No.51809189).
文摘Sustainable intensification of cropping systems is a strategy to increase productivity and reduce disservices of conventional agroecosystems.Camelina[Camelina sativa(L.)Crantz]and field pennycress(Thlaspi arvense L.)are winter annual oilseed crops well suited to fill the fallow period between corn(Zea mays L.)and soybean[Glycine max(L.)Merr.]in the U.S.northern Corn Belt,but their inclusion may be limited by resource use limitations.A 2-year study was conducted from 2015 to 2017 in the U.S.upper Midwest to evaluate the effect of double cropping on winter oilseed crops and soybean productivity and economic performance.Treatments included relay-and sequential-cropped soybean with winter camelina and field pennycress,and monocrop soybean as control.Biomass and grain yield of winter oilseed crops were not affected by cropping system.Averaged over years and cropping systems,winter camelina resulted in more biomass,nitrogen(N)uptake and grain yield by 240,186 and 139% respectively,compared to field pennycress.Soybean biomass,N uptake and yield were higher in relay relative to sequential cropping.Relay soybean resulted in similar total grain yield(soybean+winter oilseed crop)compared to monocropped soybean.Double cropping soybean could maintain net return compared to monocropped soybean.Results indicate that double cropping winter oilseed crops with soybean can be economically viable in the U.S.upper Midwest.Yet,research aimed at optimizing yield through N and water use while improving ecosystem services is needed.
