Cultivated rice (Oryza sativa L.) was domesticated from the Asian wild species O. rufipogon. Compared with cultivated rice, wild rice has spikelets/seeds with long barbed awns. In order to evaluate the role of awns in wild rice, four seed groups with different awn lengths (full, half, quarter and no awns) were prepared, and the following seed dispersal movements were investigated under simulated natural conditions as observed in the tropical Asian habitat: (1) seed detachment from the parent plant; (2) falling angle of mature seed; (3) ability to slip into small spaces; (4) horizontal movement on the ground and (5) horizontal movement in water. As a result, awns were found to enhance the detachment of matured seeds from the panicles in the initial seed dispersal step. They regulated vertical orientation in the air, and the vertical form may enable seeds to squeeze to the ground. The awned seeds also showed advantages in horizontal movements on the ground and in the water. In most of the experiments, seeds with full awns showed the best performance for seed dispersal, suggesting that wild rice keeps long awns to survive under natural conditions. Since seed awning is dominantly controlled by wild functional alleles at several loci, wild rice may be able to prevent a drastic reduction of awn length.

中文翻译：

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野生稻 (Oryza rufipogon) 芒在种子传播中的作用

栽培稻（水稻L.) 从亚洲野生物种驯化而来O. rufipogon. 与栽培稻相比，野生稻具有长刺芒的小穗/种子。为了评估芒在野生稻中的作用，准备了四个不同芒长度（全芒、半芒、四分之一芒和无芒）的种子组，并在模拟亚洲热带地区观察到的自然条件下研究了以下种子传播运动生境：（1）种子脱离亲本植物；(2)成熟种子落角；(3) 能够溜进狭小的空间；(4) 地面水平运动和 (5) 水中水平运动。结果，发现芒在最初的种子散布步骤中增强了成熟种子从圆锥花序上的分离。它们调节空气中的垂直方向，垂直形式可以使种子挤压到地面。有芒的种子在地面和水中的水平运动中也显示出优势。在大多数实验中，长芒种子的种子传播性能最好，这表明野生稻在自然条件下保持长芒生存。由于种子雨篷主要由几个基因座的野生功能等位基因控制，因此野生稻可能能够防止雨篷长度的急剧减少。