Quantitative Analysis of Benzyl Modification in Waxy Maize Starch by Fourier Transform (FT) Raman Spectroscopy

Waxy maize starch was chemically modified to varying benzylation levels and the degree of benzylation substitution was measured using a nuclear magnetic resonance (NMR) method. Fourier Transform (FT) Raman spectra of the chemically modified starches were acquired and aromatic C=C stretch Raman bands characteristic of the benzylation modification were used to derive a calibration curve for the Raman intensity of these marker bands versus the degree of benzylation substitution. The best‐fit linear regression to the plotted data gave a linear correlation coefficient of 0.997. The FT‐Raman technique provides a fast, nondestructive method for the measurement of the degree of benzylation substitution of modified waxy maize starches and should be applicable for use with benzylated starches from other botanical sources.     

紫薇与大花紫薇种间杂种子代倍性分析

以尾叶紫薇为对照，用流式细胞仪测定屋久岛紫薇、福建紫薇、大花紫薇、紫薇品种Dynamite和12株紫薇（Lagerstroemia indica）×大花紫薇（Lagerstroemia speciosa）种间杂种子代植株均为二倍体；利用8条SSR标记判定Dynamite、大花紫薇、福建紫薇和26株紫薇×大花紫薇种间杂种子代植株的倍性均为二倍体，证实了流式细胞仪和SSR标记反映植物倍性的可行性。     

不同成熟度烟株根际土壤无机氮含量与叶片SPAD值及氮含量的相关性分析

采用田间调查与室内检测相结合的方法,对云南省玉溪市澄江县烤烟生产上封顶后10～12天的不同成熟度烟株进行分析研究.结果表明,烟株根际土壤无机氮含量直接影响烟株成熟度及叶片全氮含量,而土壤水解氮(有效氮)含量高低对其基本无影响;正常落黄烟株的根际土壤无机氮含量为52.4～58.8mg/kg,5叶位、10叶位、15叶位及2...