种质库保存的烟草种子活力和出苗率及其关系

Connection on Tobacco Seed Vitality and Budding in Germplasm Resources Bank

为探索低发芽率烟草种子的出苗特性,以指导烟草种质资源的长期贮藏和繁种更新,本研究同时在人工气候箱内对贮藏3-30年、发芽率≤50%的63份和贮藏4-24年、发芽率55%-95%的8份烟草种子进行出苗率检测,分段对发芽势和发芽率不同的种子进行出苗情况分析。结果表明,种子出苗率随发芽势和发芽率段的递增而提高;各发芽势和发芽率段7d、14d的平均种子出苗率分别低于其平均发芽势和发芽率,延长到70d的平均出苗率也低于平均发芽率。随着发芽势和发芽率段的递增,出苗种子份数占该段总份数的百分率提高;当种子发芽势段从0.1%上升为20.1%-30.0%时,每份种子均能在14d内出苗;而当种子发芽率段上升至≥30.1%时,每份种子均能在7d内出苗。相关性分析结果显示：贮藏年限与发芽势、发芽率和7d出苗率间呈显著负相关;发芽势与发芽率呈正相关,发芽势、发芽率与7、14、28、70d的出苗率等各项指标之间也呈极显著正相关;贮藏20年以上的种子,其贮藏年限与7d和14d的出苗率密切相关。可见,烟草种子发芽率在30%-50%时进行繁种更新,从而防止种质资源的失传。

In order to propose the renew index of budding for tobacco germplasm resources, the emergence rates of 63 tobacco seeds whose budding rates were under 50% and stored for 3 - 30 years and 8 tobacco seeds whose budding rates were 55% -95% and stored for 4 -24 years were detected in the man-made climate controller, and the seed budding characteristics were studied according to the different germination energy subsection. The results showed that the emergence rate rose with the increasing of seed germination energy and germination percentage. The average emergence rates in the 7th day and 14th day were lower tharl their germination energy and germination percentages, even if delaying budding in the 70th day. With the increasing of seed germination energy and germination percentage, the emergence rate also rose according to its total subsection. When the seed germination energy of subsections was from 20. 1% to 30.0% , the emergence rate could reach 100% in 14th day. When the seed germination energy of subsections was higher than 30. 1%, the emergence rate could reach 100% in 7th day. The correlation analysis result showed that, the storing years had negative correlation with the seed germination energy, germination percentage and emergence rate in 7th day, while there was positive correlation between the seed germination energy and germination percentage, the seed germination energy and germination percentage had significantly positive correlation with the emergence rates in 7th, 14th, 28th and 70th day. As for the seeds stored for more than 20 years, the storing years had close correlation with the emergence rates in 7th and 14th day. Above all, it is better to carry out propagation and regeneration when the tobacco budding rates are from 30% to 50%, it is necessary for breeders to take into account of its seed reproduction, so as to prevent the loss of germplasm resources.