Water shortage has threatened sustainable development of agriculture globally as well as in the North China Plain（NCP）.Irrigation,as the most effective way to increase food production in dry land,may not be readily ...Water shortage has threatened sustainable development of agriculture globally as well as in the North China Plain（NCP）.Irrigation,as the most effective way to increase food production in dry land,may not be readily available in the situation of drought.One of the alternatives is to supply plants with enough nutrients so that they can be more sustainable to the water stress.The objective of this study was to explore effects of irrigation and sulphur（S）application on water consumption,dry matter accumulation（DMA）,and grain yield of winter wheat in NCP.Three irrigation regimes including no irrigation（rainfed,I0）during the whole growth period,once irrigation only at jointing stage（90 mm,I1）,and twice respective irrigation at jointing and anthesis stages（90 mm plus 90 mm,I2）,and two levels of S application including 0S0and 60 kg ha^–1（S60）were designed in the field experiment in NCP.Results showed that increasing irrigation times significantly increased mean grain yield of wheat by 12.5–23.7%and nitrogen partial factor productivity（NPFP）by 21.2–45.0%in two wheat seasons,but markedly decreased crop water use efficiency（YWUE）.Furthermore,S supply 60 kg ha^–1 significantly increased mean grain yield,YWUE,IWUE and NPFP by 5.6,6.1,23.2,and 5.6%（across two wheat seasons）,respectively.However,we also found that role of soil moisture prior to S application was one of important greater factors on improving the absorption and utilization of storage water and nutrients of soil.Thus,water supply is still the most important factor to restrict the growth of wheat in the present case of NCP,supplying 60 kg ha^–1 S with once irrigation 90 mm at the jointing stage is a relatively appropriate recommended combination to improve grain yield and WUE of wheat when saving water resources is be considered in irrigated wheat farmlands of NCP.展开更多
作物产量估测关系到人民生活质量和国家粮食安全问题,在田块尺度下及时准确估算产量,对于农事操作管理、收获、销售及种植计划制定均具有重要意义。选择地势起伏及空间差异较大的农田为研究区,利用低空无人机遥感平台搭载多光谱相机、...作物产量估测关系到人民生活质量和国家粮食安全问题,在田块尺度下及时准确估算产量,对于农事操作管理、收获、销售及种植计划制定均具有重要意义。选择地势起伏及空间差异较大的农田为研究区,利用低空无人机遥感平台搭载多光谱相机、热红外相机和RGB相机,同步获取小麦关键生育时期的无人机遥感影像,并提取光谱反射率、热红外温度和数字高程信息。首先统计不同地形特征下遥感参数和生长指标的空间变异情况,分析植被指数和温度参数与小麦产量的相关性,然后利用多元线性回归(multiple linear regression,MLR)、偏最小二乘回归(partial least squares regression,PLSR)、支持向量机回归(support vector machine regression,SVR)和随机森林回归(random forest regression,RFR)4种机器学习方法以单模态数据和多模态遥感信息融合2种方式进行建模,比较单模态数据和多模态数据融合的产量估测能力。结果表明,坡度是影响作物生长和产量的重要因子,3个生育期内,不同坡度等级下遥感参数差异明显,土壤含水量、植株含水量和地上部生物量与坡度的相关性均达显著水平,植被指数和温度参数与产量的相关性均达显著水平。依据与产量的相关性,筛选7个植被指数(NDVI、GNDVI、EVI2、OSAVI、SAVI、NDRE、WDRVI)和2个温度参数(NRCT、CTD)作为模型输入变量,对于单模态数据而言,对产量的估算效应为植被指数>温度参数,以灌浆期植被指数的RFR模型效果最好(R2=0.724,RMSE=614.72 kg hm^(-2),MAE=478.08 kg hm^(-2));对于双模态数据融合来说,在植被指数基础上融入冠层温度参数表现最好,开花期RFR模型效果进一步提高(R2=0.865,RMSE=440.73 kg hm^(-2),MAE=374.86 kg hm^(-2));在双模态数据基础上引入坡度信息进行三模态数据融合,其产量估算效果明显优于单模态和双模态数据融合,其中以开花期植被指数、温度参数和坡度信息融合的RFR估算效果最好(R2=0.893,RMSE=420.06 kg hm^(-2),MAE=352.69 kg hm^(-2)),模型验证效果较好(R2=0.892,RMSE=423.55 kg hm^(-2),MAE=334.43 kg hm^(-2))。可见,在本试验条件下通过引入地形因子,结合随机森林回归算法将多模态数据有效融合,可充分发挥不同遥感信息源之间互补协同作用,有效提高了产量估算模型的精度与稳定性,为作物生长监测及产量估算提供思路参考和方法支持。展开更多
The current interest in the health beneifts of whole wheat grain has prompted breeders to further increase the concentration of antioxidants in wheat. The objective of this study was to investigate the variation in an...The current interest in the health beneifts of whole wheat grain has prompted breeders to further increase the concentration of antioxidants in wheat. The objective of this study was to investigate the variation in antioxidant content among Chinese wheat grains and the relationship between antioxidants and grain color and morphological characteristics. A wide variation was observed in the total phenolic, carotenoid and lfavonoid contents, as well as the antioxidant activity （AOA）, of Chinese wheat varieties. Black wheat had the highest mean total phenolic, carotenoid and lfavonoid contents and the highest AOA, followed by red and white wheats. The grain color parameters were signiifcantly negatively correlated with total phenolic, carotenoid and lfavonoid contents and AOA among all of the wheat varieties examined, and grain weight was also signiifcantly negatively correlated with these traits. The same correlation between grain weight and antioxidant traits was also observed within individual groups of wheat, which indicates that grain weight may be used as an index for selecting wheat varieties with high AOA. Landraces had signiifcantly higher lfavonoid content than commercial wheat varieties. The results of this study may be useful for breeding nutrient-rich wheat varieties.展开更多
Increasing zinc(Zn)concentration in wheat grain is important to minimize human dietary Zn deficiency.This study aimed to investigate the effect of foliar Zn and soil nitrogen(N)applications on the accumulation and dis...Increasing zinc(Zn)concentration in wheat grain is important to minimize human dietary Zn deficiency.This study aimed to investigate the effect of foliar Zn and soil nitrogen(N)applications on the accumulation and distribution of N and Zn in grain pearling fractions,N remobilization,and the relationships between nutrient concentration in the vegetative tissues and grain or its fractions in two cropping years in the North China Plain.The results showed a progressive decrease in N and Zn concentrations from the outer to the inner parts of grain,with most of the accumulation in the core endosperm.Foliar Zn application significantly increased N concentration in the pericarp,and soil N application increased N concentration in each grain fraction.Both treatments significantly increased core endosperm Zn concentration.Foliar Zn had no effect on grain N and Zn distribution.Soil N application made N concentrated in the aleurone,promoted Zn translocation to the core endosperm and also increased N remobilization and its efficiency from the shoot to the grain,but no improved contribution to grain was found.N concentration in grain and its fractions were positively correlated with N in vegetative organs at anthesis and maturity,while positive correlations were obtained between N concentration in the pericarp and progressive central area of the endosperm and Zn concentration in the core endosperm.Thus,foliar Zn and soil N applications effectively increased yield and N and Zn concentrations in the wheat grain,particularly in the endosperm,and could be promising strategies to address Zn deficiency.展开更多
基金supported by the National Natural Science Foundation of China (31272246)the National Key Technologies R&D Program of China during the 12th Five-Year Plan period (2013BAD07B00, 2011BAD16B07 and 2015BAD26B01)the Special Fund for Agroscientific Research in the Public Interest, China (201203096, 201203079 and 201203031)
文摘Water shortage has threatened sustainable development of agriculture globally as well as in the North China Plain（NCP）.Irrigation,as the most effective way to increase food production in dry land,may not be readily available in the situation of drought.One of the alternatives is to supply plants with enough nutrients so that they can be more sustainable to the water stress.The objective of this study was to explore effects of irrigation and sulphur（S）application on water consumption,dry matter accumulation（DMA）,and grain yield of winter wheat in NCP.Three irrigation regimes including no irrigation（rainfed,I0）during the whole growth period,once irrigation only at jointing stage（90 mm,I1）,and twice respective irrigation at jointing and anthesis stages（90 mm plus 90 mm,I2）,and two levels of S application including 0S0and 60 kg ha^–1（S60）were designed in the field experiment in NCP.Results showed that increasing irrigation times significantly increased mean grain yield of wheat by 12.5–23.7%and nitrogen partial factor productivity（NPFP）by 21.2–45.0%in two wheat seasons,but markedly decreased crop water use efficiency（YWUE）.Furthermore,S supply 60 kg ha^–1 significantly increased mean grain yield,YWUE,IWUE and NPFP by 5.6,6.1,23.2,and 5.6%（across two wheat seasons）,respectively.However,we also found that role of soil moisture prior to S application was one of important greater factors on improving the absorption and utilization of storage water and nutrients of soil.Thus,water supply is still the most important factor to restrict the growth of wheat in the present case of NCP,supplying 60 kg ha^–1 S with once irrigation 90 mm at the jointing stage is a relatively appropriate recommended combination to improve grain yield and WUE of wheat when saving water resources is be considered in irrigated wheat farmlands of NCP.
文摘作物产量估测关系到人民生活质量和国家粮食安全问题,在田块尺度下及时准确估算产量,对于农事操作管理、收获、销售及种植计划制定均具有重要意义。选择地势起伏及空间差异较大的农田为研究区,利用低空无人机遥感平台搭载多光谱相机、热红外相机和RGB相机,同步获取小麦关键生育时期的无人机遥感影像,并提取光谱反射率、热红外温度和数字高程信息。首先统计不同地形特征下遥感参数和生长指标的空间变异情况,分析植被指数和温度参数与小麦产量的相关性,然后利用多元线性回归(multiple linear regression,MLR)、偏最小二乘回归(partial least squares regression,PLSR)、支持向量机回归(support vector machine regression,SVR)和随机森林回归(random forest regression,RFR)4种机器学习方法以单模态数据和多模态遥感信息融合2种方式进行建模,比较单模态数据和多模态数据融合的产量估测能力。结果表明,坡度是影响作物生长和产量的重要因子,3个生育期内,不同坡度等级下遥感参数差异明显,土壤含水量、植株含水量和地上部生物量与坡度的相关性均达显著水平,植被指数和温度参数与产量的相关性均达显著水平。依据与产量的相关性,筛选7个植被指数(NDVI、GNDVI、EVI2、OSAVI、SAVI、NDRE、WDRVI)和2个温度参数(NRCT、CTD)作为模型输入变量,对于单模态数据而言,对产量的估算效应为植被指数>温度参数,以灌浆期植被指数的RFR模型效果最好(R2=0.724,RMSE=614.72 kg hm^(-2),MAE=478.08 kg hm^(-2));对于双模态数据融合来说,在植被指数基础上融入冠层温度参数表现最好,开花期RFR模型效果进一步提高(R2=0.865,RMSE=440.73 kg hm^(-2),MAE=374.86 kg hm^(-2));在双模态数据基础上引入坡度信息进行三模态数据融合,其产量估算效果明显优于单模态和双模态数据融合,其中以开花期植被指数、温度参数和坡度信息融合的RFR估算效果最好(R2=0.893,RMSE=420.06 kg hm^(-2),MAE=352.69 kg hm^(-2)),模型验证效果较好(R2=0.892,RMSE=423.55 kg hm^(-2),MAE=334.43 kg hm^(-2))。可见,在本试验条件下通过引入地形因子,结合随机森林回归算法将多模态数据有效融合,可充分发挥不同遥感信息源之间互补协同作用,有效提高了产量估算模型的精度与稳定性,为作物生长监测及产量估算提供思路参考和方法支持。
基金funded by the Special Funds for AgroScientifc Research in the Public Interest,China (201203031)the Key Technologies R&D Program of China during the 12th Five-Year Plan period (2011BAD16B07-2)the National Agriculture Technology Research System of China (CARS-03)
文摘The current interest in the health beneifts of whole wheat grain has prompted breeders to further increase the concentration of antioxidants in wheat. The objective of this study was to investigate the variation in antioxidant content among Chinese wheat grains and the relationship between antioxidants and grain color and morphological characteristics. A wide variation was observed in the total phenolic, carotenoid and lfavonoid contents, as well as the antioxidant activity （AOA）, of Chinese wheat varieties. Black wheat had the highest mean total phenolic, carotenoid and lfavonoid contents and the highest AOA, followed by red and white wheats. The grain color parameters were signiifcantly negatively correlated with total phenolic, carotenoid and lfavonoid contents and AOA among all of the wheat varieties examined, and grain weight was also signiifcantly negatively correlated with these traits. The same correlation between grain weight and antioxidant traits was also observed within individual groups of wheat, which indicates that grain weight may be used as an index for selecting wheat varieties with high AOA. Landraces had signiifcantly higher lfavonoid content than commercial wheat varieties. The results of this study may be useful for breeding nutrient-rich wheat varieties.
基金the National Key Research and Development Program of China(2018YFD0300707 and 2016YFD0300400)the Modern Wheat Industrial Technology System of Henan Province,China(S2010-01-G07).
文摘Increasing zinc(Zn)concentration in wheat grain is important to minimize human dietary Zn deficiency.This study aimed to investigate the effect of foliar Zn and soil nitrogen(N)applications on the accumulation and distribution of N and Zn in grain pearling fractions,N remobilization,and the relationships between nutrient concentration in the vegetative tissues and grain or its fractions in two cropping years in the North China Plain.The results showed a progressive decrease in N and Zn concentrations from the outer to the inner parts of grain,with most of the accumulation in the core endosperm.Foliar Zn application significantly increased N concentration in the pericarp,and soil N application increased N concentration in each grain fraction.Both treatments significantly increased core endosperm Zn concentration.Foliar Zn had no effect on grain N and Zn distribution.Soil N application made N concentrated in the aleurone,promoted Zn translocation to the core endosperm and also increased N remobilization and its efficiency from the shoot to the grain,but no improved contribution to grain was found.N concentration in grain and its fractions were positively correlated with N in vegetative organs at anthesis and maturity,while positive correlations were obtained between N concentration in the pericarp and progressive central area of the endosperm and Zn concentration in the core endosperm.Thus,foliar Zn and soil N applications effectively increased yield and N and Zn concentrations in the wheat grain,particularly in the endosperm,and could be promising strategies to address Zn deficiency.
