Plant extinctions are happening tens to hundreds of times faster than the background extinction rate, and thus there is an urgent need for effective plant conservation. There are two classic approaches to halt the loss of plant diversity: in situ conservation of wild or restored populations; and ex situ conservation, which involves managing living collections of plants (for example, at botanical gardens), tissues and seeds. Ex situ conservation provides insurance that species will not be lost from our planet as well as mechanism to preserve a species’ genetic diversity outside of its natural habitat.

The ability to bank pollen of exceptional plant species would enable a less-expensive, long-term germplasm storage option compared to living collections, as well as more purposeful management of living plant collections². Although used for many agriculturally important species, little is known about pollen banking for wild species⁵. Similar to seed conservation, pollen longevity can be extended by desiccating and subsequent cooling. However, species-specific a priori knowledge is necessary to determine whether pollen is tolerant of desiccation and freezing, which thus enables long-term storage at conventional conditions of seed or gene banks. In angiosperms, at the time of pollen dispersal, pollen of a particular species is either binucleate (that is, two-celled (bicellular)) or trinucleate (that is, three-celled (tricellular)) (Fig. 1). The current dogma surrounding this developmental stage is that binucleate pollen tends to have greater desiccation tolerance and longevity than trinucleate pollen⁵. Although empirical testing of these traits on a species-by-species basis is recommended⁵, investigations into pollen desiccation tolerance and longevity in diverse wild species are almost absent.

植物灭绝的发生速度比背景灭绝速度快数十至数百倍，因此迫切需要有效的植物保护。有两种经典方法可以阻止植物多样性的丧失：对野生或恢复种群进行就地保护；异地保护，涉及管理植物（例如植物园）、组织和种子的活体收藏。异地保护提供了物种不会从地球上消失的保障，以及在自然栖息地之外保护物种遗传多样性的机制。

与活植物收藏相比，储存特殊植物物种的花粉的能力将提供一种更便宜的长期种质储存选择，以及对活植物收藏进行更有目的的管理 ² 。尽管用于许多农业上重要的物种，但对野生物种的花粉库知之甚少 ⁵ 。与种子保存类似，花粉寿命可以通过干燥和随后的冷却来延长。然而，需要特定物种的先验知识来确定花粉是否耐受干燥和冷冻，从而能够在种子或基因库的常规条件下长期保存。在被子植物中，在花粉传播时，特定物种的花粉要么是双核的（即双细胞的（bicellular）），要么是三核的（即三细胞的（tricellular））（图1）。当前围绕该发育阶段的教条是双核花粉往往比三核花粉具有更大的干燥耐受性和寿命 ⁵ 。尽管建议对每个物种的这些性状进行实证测试 ⁵ ，但几乎没有对不同野生物种的花粉干燥耐受性和寿命进行研究。