School of Landscape Architecture, Beijing Forestry University, Beijing Key Laboratory of Ornamental Plants Germplasm Innovation & Molecular Breeding, National Engineering Research Center for Floriculture, Beijing Laboratory of Urban and Rural Ecological Environment, Beijing, 100083, China.
Cryobiology. 2024 Jun;115:104867. doi: 10.1016/j.cryobiol.2024.104867. Epub 2024 Feb 20.
Pollen, as the male gametophyte, carries half of plant genetic information and is an important source of germplasm. The cryopreservation of pollen can not only preserve germplasm, but also solve the problem of time and space barrier in crossbreeding. So it is of great significance to explore the mechanism of pollen viability maintenance after cryopreservation. In this paper, 10 cultivars of Paeonia lactiflora with different fresh pollen viability that did not change after cryopreservation were taken as objects and the effects of pollen inclusions such as soluble sugar, starch, soluble protein, free amino acids, and proline were explored. The results showed that: (1) The contents of pollen inclusions in the fresh pollen of 10 cultivars were different. After cryopreservation, the contents of starch and free amino acids significantly decreased in 10 cultivars, and the soluble sugar, soluble protein, and proline varied with cultivars. (2) Correlation analysis showed that fresh pollen viability was significantly positively correlated with the soluble sugar (R-values of 0.630) and starch content (R-values of 0.694) in fresh pollen. But after cryopreservation pollen viability was only significantly positively correlated with the starch content (R-values of 0.725). These results suggest that the effects of pollen inclusions on pollen vitality are different before and after cryopreservation. The fresh pollen with higher soluble sugar and starch is more vital. But after cryopreservation, the pollen with high starch content has higher viability. The maintenance of stable pollen viability after cryopreservation appears to be related to starch content or starch metabolism, which requires further to study for a final determination.
花粉作为雄性配子体，携带植物一半的遗传信息，是种质资源的重要来源。花粉的超低温保存不仅可以保存种质资源，还可以解决杂交过程中的时空障碍问题。因此，探索花粉超低温保存后活力维持的机制具有重要意义。本文以 10 个花粉新鲜活力在超低温保存后未发生变化的牡丹品种为研究对象，探讨了可溶性糖、淀粉、可溶性蛋白、游离氨基酸和脯氨酸等花粉内含物对花粉活力的影响。结果表明：（1）10 个品种花粉内含物的含量不同。超低温保存后，10 个品种的花粉中淀粉和游离氨基酸含量显著降低，而可溶性糖、可溶性蛋白和脯氨酸的含量随品种而变化。（2）相关分析表明，新鲜花粉活力与新鲜花粉中可溶性糖（R 值为 0.630）和淀粉含量（R 值为 0.694）呈显著正相关。但超低温保存后花粉活力仅与淀粉含量呈显著正相关（R 值为 0.725）。这些结果表明，花粉内含物对花粉活力的影响在超低温保存前后不同。新鲜花粉中可溶性糖和淀粉含量较高的花粉活力较高。但超低温保存后，淀粉含量较高的花粉活力较高。超低温保存后花粉活力的稳定维持似乎与淀粉含量或淀粉代谢有关，需要进一步研究以确定最终结果。
