玉米杂交当代籽粒含水率遗传效应研究

为研究不同父本自交系对杂交当代籽粒含水率的影响,以籽粒脱水速率较慢的5个杂交种和5个自交系为母本,以脱水性能较好的5个早熟自交系为父本,10个母本分别人工授粉进行自交及与父本杂交,并对授粉后52天(DAP,d)的杂交当代籽粒及所有亲本材料的自交籽粒含水率进行了测试分析。结果表明:在早熟自交系授粉后,母本杂交授粉当代的籽粒含水率均值下降3.04个百分点,单粒干重比自交增加5.63%;母本自交系籽粒含水率均值下降2.85个百分点,单粒干重增加7.18%;当代杂交籽粒的含水率与父本呈正相关,表明玉米籽粒脱水性能具有父本效应,早熟父本可降低杂交当代籽粒的含水率。本研究可为玉米种质脱水性能的改良和选育快速脱水适宜机收的玉米品种提供参考。

Current generation genetic effect of the kernel moisture content in maize

To study the paternal effect of maize kernel moisture, five hybrids and five inbred lines with low dehydration rate were used as female parents, and five early-maturing inbred lines with good dehydration performance were used as male parents. Pollinations were made between male and female parents, meanwhile, control groups were obtained by self-pollinating of parental lines. Kernels derived from both crossing- and selfing-pollination was sampled at 52 days after pollination(DAP, d), and then used for single-kernel moisture quantification. The result showed that the moisture of kernels derived from hybrids×early-maturing male parents decreased by 3. 04 percentage point, and was accompanied by 5. 63% increase in single-kernel weight compared with the selfing kernels of female hybrids; Similarly, the moisture of kernels derived from inbred lines×early-maturing male parents was reduced by 2. 85 percentage point, and was accompanied by 7. 18% increase in single-kernel weight compared with the selfing kernels of female inbred lines. In conclusion, strong positive correlation of moisture exists between crossed kernels and selfing kernels of male parents, and early-maturing male parents could reduce moisture of kernels when pollinating to female parents with low dehydration rate. This research provides a reference to develop methods and germplasms suitable for kernel mechanized harvesting of maize.