Pollen adhesion and hydration are the earliest events of the pollen–stigma interactions, which allow compatible pollen to fertilize egg cells, but the underlying mechanisms are still poorly understood. Rice pollen are wind dispersed, and its pollen coat contains less abundant lipids than that of insect‐pollinated plants. Here, we characterized the role of OsGL1‐4, a rice member of the Glossy family, in pollen adhesion and hydration. OsGL1‐4 is preferentially expressed in pollen and tapetal cells and is required for the synthesis of very long chain alkanes. osgl1‐4 mutant generated apparently normal pollen but displayed excessively fast dehydration at anthesis and defective adhesion and hydration under normal condition, but the defective adhesion and hydration were rescued by high humidity. Gas chromatography–mass spectrometry analysis suggested that the humidity‐sensitive male sterility of osgl1‐4 was probably due to a significant reduction in C25 and C27 alkanes. These results indicate that very long chain alkanes are components of rice pollen coat and control male fertility via affecting pollen adhesion and hydration in response to environmental humidity. Moreover, we proposed that a critical point of water content in mature pollen is required for the initiation of pollen adhesion.
花粉粘附和水合作用是花粉-柱頭相互作用的最早事件，允許親和的花粉使卵細胞受精，但其機制仍不清楚。水稻花粉是風散性的，其花粉層中的脂類含量低于昆蟲授粉植物。本文，我們描述了OsGL1‐4，一個水稻Glossy家族的成員，在花粉粘附和水合作用中起作用。OsGL1-4主要在花粉和絨氈層細胞中表達，是合成長鏈烷烴所必需的。突變體osgl1‐4在正常條件下產(chǎn)生了明顯正常的花粉，但在開花期表現(xiàn)出脫水過快，花粉粘附和水合作用缺陷，但在高濕度條件下，粘附和水合作用缺陷被挽救。氣相色譜-質譜分析表明，osgl1‐4的濕敏雄性不育可能是由于C25和C27烷烴的顯著減少。這些結果表明，極長鏈烷烴是水稻花粉外被的組成部分，通過影響花粉的粘附和水合作用來控制水稻雄性育性。此外，我們還提出了成熟花粉含水量的臨界點是花粉粘附的起始點。