The distributions of light and nitrogen within a plant's canopy reflect the growth adaptation of crops to the environment and are conducive to improving the carbon assimilation ability.So can the yield in crop pro...The distributions of light and nitrogen within a plant's canopy reflect the growth adaptation of crops to the environment and are conducive to improving the carbon assimilation ability.So can the yield in crop production be maximized by improving the light and nitrogen distributions without adding any additional inputs?In this study,the effects of different nitrogen application rates and planting densities on the canopy light and nitrogen distributions of two highyielding maize cultivars(XY335 and DH618)and the regulatory effects of canopy physiological characteristics on radiation use efficiency(RUE)and yield were studied based on high-yield field experiments in Qitai,Xinjiang Uygur Autonomous Region,China,during 2019 and 2020.The results showed that the distribution of photosynthetically active photon flux density(PPFD)in the maize canopy decreased from top to bottom,while the vertical distribution of specific leaf nitrogen(SLN)initially increased and then decreased from top to bottom in the canopy.When SLN began to decrease,the PPDF values of XY335 and DH618 were 0.5 and 0.3,respectively,corresponding to 40.6 and49.3%of the total leaf area index(LAI).Nitrogen extinction coefficient(K_(N))/light extinction coefficient(K_(L))ratio in the middle and lower canopy of XY335(0.32)was 0.08 higher than that of DH618(0.24).The yield and RUE of XY335(17.2 t ha^(-1)and 1.8g MJ^(-1))were 7.0%(1.1 t ha^(-1))and 13.7%(0.2 g MJ^(-1))higher than those of DH618(16.1 t ha^(-1)and 1.6 g MJ^(-1)).Therefore,better light conditions(where the proportion of LAI in the upper and middle canopy was small)improved the light distribution when SLN started to decline,thus helping to mobilize the nitrogen distribution and maintain a high K_(N)and K_(N)/K_(L)ratio.In addition,K_(N)/K_(L)was a key parameter for yield improvement when the maize nutrient requirements were met at 360 kg N ha^(-1).At this level,an appropriately optimized high planting density could promote nitrogen utilization and produce higher yields and greater efficiency.The results of this study will be important for achieving high maize yields and the high efficiency cultivation and breeding of maize in the future.展开更多
Highlights Hybrid-Maize Model’s performance under dense planting conditions were investigated across China.Hybrid-Maize Model performed well in the simulation of maize grain yield and aboveground biomass under dense ...Highlights Hybrid-Maize Model’s performance under dense planting conditions were investigated across China.Hybrid-Maize Model performed well in the simulation of maize grain yield and aboveground biomass under dense planting conditions.Future model modifications and corrections should focus on the leaf area index dynamics and harvest index.展开更多
Worldwide, scarce water resources and substantial food demands require efficient water use and high yield.This study investigated whether irrigation frequency can be used to adjust soil moisture to increase grain yiel...Worldwide, scarce water resources and substantial food demands require efficient water use and high yield.This study investigated whether irrigation frequency can be used to adjust soil moisture to increase grain yield and water use efficiency(WUE) of high-yield maize under conditions of mulching and drip irrigation.A field experiment was conducted using three irrigation intervals in 2016: 6, 9, and 12 days(labeled D6, D9, and D12) and five irrigation intervals in 2017: 3, 6, 9, 12, and 15 days(D3, D6, D9, D12, and D15).In Xinjiang, an optimal irrigation quota is 540 mm for high-yield maize.The D3, D6, D9, D12, and D15 irrigation intervals gave grain yields of 19.7, 19.1–21.0, 18.8–20.0, 18.2–19.2, and 17.2 Mg ha^-1 and a WUE of 2.48, 2.53–2.80, 2.47–2.63, 2.34–2.45, and 2.08 kg m-3, respectively.Treatment D6 led to the highest soil water storage, but evapotranspiration and soil-water evaporation were lower than other treatments.These results show that irrigation interval D6 can help maintain a favorable soil-moisture environment in the upper-60-cm soil layer, reduce soilwater evaporation and evapotranspiration, and produce the highest yield and WUE.In this arid region and in other regions with similar soil and climate conditions, a similar irrigation interval would thus be beneficial for adjusting soil moisture to increase maize yield and WUE under conditions of mulching and drip irrigation.展开更多
The reasonable assessment of maize varieties in different ecological regions can allow temperature resources to be fully exploited and reach the goal of high yield and efficiency and is thus an important direction of ...The reasonable assessment of maize varieties in different ecological regions can allow temperature resources to be fully exploited and reach the goal of high yield and efficiency and is thus an important direction of modern maize development in China.In this study,a logistic power nonlinear growth model was used to simulate the accumulated temperature required for kernel dehydration to moisture contents of 25%,20%,and 16%for various maize cultivar,which were divided into six types based on the accumulated temperature required for kernel dehydration to a moisture content of 25%.The relationship between the yield of maize cultivars and the accumulated temperature required for kernel dehydration to a moisture content of 25%was found to follow a unary function model.Changing the planted maize variety was found to increase economic returns by more than 7000 RMB/hm2 in Ningxia,Northwest China.Under the conditions of mechanical grain harvesting,economic benefits can be further increased by means of selecting high yields and fast-dehydrating varieties,selling when the grain dehydration is below 16%.A better way to achieve grain dehydration to a moisture content below 16%is to postpone the harvest date as much as possible rather than drying after the harvest at physiological maturity.The areas of various types of maize varieties can be dehydrated to moisture contents of 25%,20%,and 16%were marked.Based on the distribution of heat resources in different regions of Ningxia from the normal sowing date to October 31 before winter irrigation,the appropriate cultivars for various regions in the province were determined based on production benefits.Therefore,in different areas of Ningxia,selecting suitable maize varieties according to temperature resources can reach a high yield and mechanical kernel harvesting,and ultimately obtain higher economic benefits.展开更多
基金supported by the National Natural Science Foundation of China(32172118)the National Key Research and Development Program of China(2016YFD0300110 and 2016YFD0300101)+1 种基金the Basic Scientific Research Fund of Chinese Academy of Agricultural Sciences,China(S2022ZD05)the Agricultural Science and Technology Innovation Program,China(CAAS-ZDRW202004)。
文摘The distributions of light and nitrogen within a plant's canopy reflect the growth adaptation of crops to the environment and are conducive to improving the carbon assimilation ability.So can the yield in crop production be maximized by improving the light and nitrogen distributions without adding any additional inputs?In this study,the effects of different nitrogen application rates and planting densities on the canopy light and nitrogen distributions of two highyielding maize cultivars(XY335 and DH618)and the regulatory effects of canopy physiological characteristics on radiation use efficiency(RUE)and yield were studied based on high-yield field experiments in Qitai,Xinjiang Uygur Autonomous Region,China,during 2019 and 2020.The results showed that the distribution of photosynthetically active photon flux density(PPFD)in the maize canopy decreased from top to bottom,while the vertical distribution of specific leaf nitrogen(SLN)initially increased and then decreased from top to bottom in the canopy.When SLN began to decrease,the PPDF values of XY335 and DH618 were 0.5 and 0.3,respectively,corresponding to 40.6 and49.3%of the total leaf area index(LAI).Nitrogen extinction coefficient(K_(N))/light extinction coefficient(K_(L))ratio in the middle and lower canopy of XY335(0.32)was 0.08 higher than that of DH618(0.24).The yield and RUE of XY335(17.2 t ha^(-1)and 1.8g MJ^(-1))were 7.0%(1.1 t ha^(-1))and 13.7%(0.2 g MJ^(-1))higher than those of DH618(16.1 t ha^(-1)and 1.6 g MJ^(-1)).Therefore,better light conditions(where the proportion of LAI in the upper and middle canopy was small)improved the light distribution when SLN started to decline,thus helping to mobilize the nitrogen distribution and maintain a high K_(N)and K_(N)/K_(L)ratio.In addition,K_(N)/K_(L)was a key parameter for yield improvement when the maize nutrient requirements were met at 360 kg N ha^(-1).At this level,an appropriately optimized high planting density could promote nitrogen utilization and produce higher yields and greater efficiency.The results of this study will be important for achieving high maize yields and the high efficiency cultivation and breeding of maize in the future.
基金supported by the National Key Research and Development Program of China(2023YFD1900603)the National Natural Science Foundation of China(32172118)the China Agriculture Research System of MOF and MARA(CARS-02)。
文摘Highlights Hybrid-Maize Model’s performance under dense planting conditions were investigated across China.Hybrid-Maize Model performed well in the simulation of maize grain yield and aboveground biomass under dense planting conditions.Future model modifications and corrections should focus on the leaf area index dynamics and harvest index.
基金research support from the National Key Research and Development Program of China (2016YFD0300110, 2016YFD0300101)the National Basic Research Program of China (2015CB150401)+2 种基金the National Natural Science Foundation of China (31360302)the Science and Technology Program of the Sixth Division of Xinjiang Construction Corps in China (1703)the Agricultural Science and Technology Innovation Program for financial support.
文摘Worldwide, scarce water resources and substantial food demands require efficient water use and high yield.This study investigated whether irrigation frequency can be used to adjust soil moisture to increase grain yield and water use efficiency(WUE) of high-yield maize under conditions of mulching and drip irrigation.A field experiment was conducted using three irrigation intervals in 2016: 6, 9, and 12 days(labeled D6, D9, and D12) and five irrigation intervals in 2017: 3, 6, 9, 12, and 15 days(D3, D6, D9, D12, and D15).In Xinjiang, an optimal irrigation quota is 540 mm for high-yield maize.The D3, D6, D9, D12, and D15 irrigation intervals gave grain yields of 19.7, 19.1–21.0, 18.8–20.0, 18.2–19.2, and 17.2 Mg ha^-1 and a WUE of 2.48, 2.53–2.80, 2.47–2.63, 2.34–2.45, and 2.08 kg m-3, respectively.Treatment D6 led to the highest soil water storage, but evapotranspiration and soil-water evaporation were lower than other treatments.These results show that irrigation interval D6 can help maintain a favorable soil-moisture environment in the upper-60-cm soil layer, reduce soilwater evaporation and evapotranspiration, and produce the highest yield and WUE.In this arid region and in other regions with similar soil and climate conditions, a similar irrigation interval would thus be beneficial for adjusting soil moisture to increase maize yield and WUE under conditions of mulching and drip irrigation.
基金This research was supported by the National Key Research and Development Program of China(2016YFD0300110)the National Natural Science Foundation of China(31971849)+1 种基金the National Maize Industrial Technology System of China(CARS-02)the Science and Technology Innovation Project of the Chinese Academy of Agricultural Science and the Key Research and Development Program of Ningxia(2018BBF02018)for their financial support.
文摘The reasonable assessment of maize varieties in different ecological regions can allow temperature resources to be fully exploited and reach the goal of high yield and efficiency and is thus an important direction of modern maize development in China.In this study,a logistic power nonlinear growth model was used to simulate the accumulated temperature required for kernel dehydration to moisture contents of 25%,20%,and 16%for various maize cultivar,which were divided into six types based on the accumulated temperature required for kernel dehydration to a moisture content of 25%.The relationship between the yield of maize cultivars and the accumulated temperature required for kernel dehydration to a moisture content of 25%was found to follow a unary function model.Changing the planted maize variety was found to increase economic returns by more than 7000 RMB/hm2 in Ningxia,Northwest China.Under the conditions of mechanical grain harvesting,economic benefits can be further increased by means of selecting high yields and fast-dehydrating varieties,selling when the grain dehydration is below 16%.A better way to achieve grain dehydration to a moisture content below 16%is to postpone the harvest date as much as possible rather than drying after the harvest at physiological maturity.The areas of various types of maize varieties can be dehydrated to moisture contents of 25%,20%,and 16%were marked.Based on the distribution of heat resources in different regions of Ningxia from the normal sowing date to October 31 before winter irrigation,the appropriate cultivars for various regions in the province were determined based on production benefits.Therefore,in different areas of Ningxia,selecting suitable maize varieties according to temperature resources can reach a high yield and mechanical kernel harvesting,and ultimately obtain higher economic benefits.
