The outer wall of epidermal cells with spininess becomes slightly thick at mature pollen stage.

表皮细胞外壁在花粉成熟时期略有增厚，且具小刺状突起。

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The outer wall of epidermal cells with spininess becomes slightly thick at mature pollen stage.

表皮细胞外壁在花粉成熟时期略有增厚，且具小刺状突起。

youdao