该研究基于近红外光谱分析技术(near infrared spectroscopy,NIRS),结合偏最小二乘法(partial least squares,PLS),建立刺糖中多糖含量的快速检测定量模型。以100批次刺糖为研究对象,采用苯酚-硫酸法测定多糖含量作为参比值,并采集780~2...该研究基于近红外光谱分析技术(near infrared spectroscopy,NIRS),结合偏最小二乘法(partial least squares,PLS),建立刺糖中多糖含量的快速检测定量模型。以100批次刺糖为研究对象,采用苯酚-硫酸法测定多糖含量作为参比值,并采集780~2500 nm的近红外光谱。通过比较多种光谱预处理方法,卷积平滑法(savitzky-Golay smoothing,SG)、标准正态变量(standard normal variate,SNV)、多元散射校正(multiplicative scatter correction,MSC)、一阶导数(first derivative,FD)、二阶导数(second derivative,SD)及其组合;以决定系数(coefficient of determination,R^(2))、校正均方根偏差(root mean square error of calibration,RMSEC)、预测均方根偏差(root mean square error of prediction,RMSEP)为评价参数,确定FD+SNV为最佳预处理方式,建模特征波段为1100~1300 nm、1350~1500 nm、1600~1800 nm、2000~2300 nm,主因子数为5。所建模型性能优异(校正集:R_(c)^(2)=0.9741,RMSEC=0.0966;预测集:R_(p)^(2)=0.9859,RMSEP=0.0663),线性关系良好。进一步验证结果证实模型预测准确、稳定性良好,可用于刺糖中多糖的快速测定,为其质量评价和规模化开发利用提供技术支持。展开更多
[Objective] The influence of mixed silage of A.sparsifolia and M.sativa at initial flowering stage on degradation was studied to provide theoretical basis for production practice.[Method] Using A.sparsifolia and M.sat...[Objective] The influence of mixed silage of A.sparsifolia and M.sativa at initial flowering stage on degradation was studied to provide theoretical basis for production practice.[Method] Using A.sparsifolia and M.sativa at initial flowering stage as materials,the changes of in vitro degradation rate,gas production,pH value,ammoniacal nitrogen（NH3-N）and volatile fatty acid（VFA）content in degradation solution were analyzed by means of artificial rumen technique,and the effect of mixed silage of A.sparsifolia and M.sativa at initial flowering stage on degradation was studied in order to find out suitable mixed silage ratio of A.sparsifolia and M.sativa.[Result] Compared with single M.sativa,NH3-N content in degradation solution was very significantly decreased in the mixed silage of A.sparsifolia and M.sativa,and there was a reduction in gas production,while the content of acetic acid,propionic acid and butyric acid increased significantly;for the treatment of 70% A.sparsifolia and 30% M.sativa,NH3-N content（22.93 mmol/L）and gas production（40.50 ml）was lowest,while degradation rate（32.27%）,acetic acid（5.48 mmol/L）,propionic acid（2.08 mmol/L）,butyric acid（2.52 mmol/L）and their total content（10.08 mmol/L）were highest,so its degradation effect was the best.[Conclusion] The mixed silage of A.sparsifolia and M.sativa at initial flowering stage could improve the utilization efficiency of protein and carbohydrate in M.sativa and the treatment of 70% A.sparsifolia and 30% M.sativa had the best degradation effect.展开更多
Water relations of Alhagi sparsifolia Shap. at the transition zone between oases and sandy desert were studied in the southern fringe of Taklamakan Desert. Results showed that A. sparsifolia maintained the positive tu...Water relations of Alhagi sparsifolia Shap. at the transition zone between oases and sandy desert were studied in the southern fringe of Taklamakan Desert. Results showed that A. sparsifolia maintained the positive turgor during the summer. The steady high predawn water potential (psi(P)) indicated A. sparsifolia had sufficient hydration and water supply in growing season. In July, water deficit caused by drought stress had no effect on the transpiration of A. sparsifolia. Therefore, drought stress is not a main factor affecting the survival of plants. The physiological adaptation to drought of A. sparsifolia was shown mainly at the leaf level by significant difference (DeltaII) and relative water content (RWC) between the osmotic pressure at full turgor and at turgor loss, by occurring of osmotic adjustment, by high percentage of dry mass-related water content ( WCsat), by RWC at turgor loss point ( RWCp) in stable level and low RWC of the saturated symplast (RWCsym). However, the morphological features of transpiring surface reduction and deep root system seem to be the main way for the plant to adapt to the extreme drought environment. Result also suggests that one time of irregular irrigation in summer will not be helpful to recover water status of A. sparsifolia in location where the water table is very low.展开更多
文摘该研究基于近红外光谱分析技术(near infrared spectroscopy,NIRS),结合偏最小二乘法(partial least squares,PLS),建立刺糖中多糖含量的快速检测定量模型。以100批次刺糖为研究对象,采用苯酚-硫酸法测定多糖含量作为参比值,并采集780~2500 nm的近红外光谱。通过比较多种光谱预处理方法,卷积平滑法(savitzky-Golay smoothing,SG)、标准正态变量(standard normal variate,SNV)、多元散射校正(multiplicative scatter correction,MSC)、一阶导数(first derivative,FD)、二阶导数(second derivative,SD)及其组合;以决定系数(coefficient of determination,R^(2))、校正均方根偏差(root mean square error of calibration,RMSEC)、预测均方根偏差(root mean square error of prediction,RMSEP)为评价参数,确定FD+SNV为最佳预处理方式,建模特征波段为1100~1300 nm、1350~1500 nm、1600~1800 nm、2000~2300 nm,主因子数为5。所建模型性能优异(校正集:R_(c)^(2)=0.9741,RMSEC=0.0966;预测集:R_(p)^(2)=0.9859,RMSEP=0.0663),线性关系良好。进一步验证结果证实模型预测准确、稳定性良好,可用于刺糖中多糖的快速测定,为其质量评价和规模化开发利用提供技术支持。
基金Supported by National Natural Science Foundation of China(30960256)Scientific Research Special Fund for Public WelfareIndustry(nyhyzx07-022)Project of Key Laboratory of Tarim Animal Husbandry Science and Technology,Xinjiang Production and Construction Group(HS20802)~~
文摘[Objective] The influence of mixed silage of A.sparsifolia and M.sativa at initial flowering stage on degradation was studied to provide theoretical basis for production practice.[Method] Using A.sparsifolia and M.sativa at initial flowering stage as materials,the changes of in vitro degradation rate,gas production,pH value,ammoniacal nitrogen（NH3-N）and volatile fatty acid（VFA）content in degradation solution were analyzed by means of artificial rumen technique,and the effect of mixed silage of A.sparsifolia and M.sativa at initial flowering stage on degradation was studied in order to find out suitable mixed silage ratio of A.sparsifolia and M.sativa.[Result] Compared with single M.sativa,NH3-N content in degradation solution was very significantly decreased in the mixed silage of A.sparsifolia and M.sativa,and there was a reduction in gas production,while the content of acetic acid,propionic acid and butyric acid increased significantly;for the treatment of 70% A.sparsifolia and 30% M.sativa,NH3-N content（22.93 mmol/L）and gas production（40.50 ml）was lowest,while degradation rate（32.27%）,acetic acid（5.48 mmol/L）,propionic acid（2.08 mmol/L）,butyric acid（2.52 mmol/L）and their total content（10.08 mmol/L）were highest,so its degradation effect was the best.[Conclusion] The mixed silage of A.sparsifolia and M.sativa at initial flowering stage could improve the utilization efficiency of protein and carbohydrate in M.sativa and the treatment of 70% A.sparsifolia and 30% M.sativa had the best degradation effect.
文摘Water relations of Alhagi sparsifolia Shap. at the transition zone between oases and sandy desert were studied in the southern fringe of Taklamakan Desert. Results showed that A. sparsifolia maintained the positive turgor during the summer. The steady high predawn water potential (psi(P)) indicated A. sparsifolia had sufficient hydration and water supply in growing season. In July, water deficit caused by drought stress had no effect on the transpiration of A. sparsifolia. Therefore, drought stress is not a main factor affecting the survival of plants. The physiological adaptation to drought of A. sparsifolia was shown mainly at the leaf level by significant difference (DeltaII) and relative water content (RWC) between the osmotic pressure at full turgor and at turgor loss, by occurring of osmotic adjustment, by high percentage of dry mass-related water content ( WCsat), by RWC at turgor loss point ( RWCp) in stable level and low RWC of the saturated symplast (RWCsym). However, the morphological features of transpiring surface reduction and deep root system seem to be the main way for the plant to adapt to the extreme drought environment. Result also suggests that one time of irregular irrigation in summer will not be helpful to recover water status of A. sparsifolia in location where the water table is very low.
