基于低场核磁共振技术的玉米单子粒含水率测定方法研究

利用低场核磁共振技术分别采集硫酸铜溶液与郑单958子粒水分核磁共振信号,根据其T2弛豫图谱信质比相关关系,建立用于玉米单子粒含水率测定的核磁共振标线NMRM。与烘干法测得子粒含水率比较发现,当标线测量水分范围为13%~37%时,测量偏差为±1.5%,且含水率大于18%时,绝对偏差均处于±1%以内。利用标线对不同子粒含水率进行测定,与烘干法比较发现,平均偏差均小于1%;最大偏差在1.5%以内,说明本研究所建立标线基本可满足玉米单子粒含水率测量要求,可为玉米子粒水分遗传机理研究和机收品种选育提供新的技术手段。

Single Kernel Moisture Content Evaluation Based on Low Field Nuclear Magnetic Resonance in Maize

The measurement of single kernel moisture content was realized by using NMR method to build the testing model of the moisture content measurement of single kernel. In the model, copper sulfate solution was used to simulate the change of maize kernels, based on the similarity T2 relaxation time of NMR model(NMRM) could be obtained by curve fitting with similar maximum T2 relaxation time and detection measurement range through real maize kernel moisture. True value of the kernel moisture was measured by standardized oven-drying methods. The results indicated that effective measurement intervals of NMRM was 13%-37%,when absolute deviation was within ±1.5%. While moisture content of kernel was greater than 18%, all absolute deviation was within ±1%. By compared with standardized oven-drying methods, the results indicated that average absolute deviation was under 1% and maximum absolute deviation was basically within 1.5%, which was acceptable in breeding programs for single kernel selection. This research proved the NMR will give the powerful support to the breeding programs of maize mechanized harvesting.