The role of wild rice (Oryza rufipogon) awns in seed dispersal
The role of wild rice (Oryza rufipogon) awns in seed dispersal
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DOI：
10.1017/s096025852000046x
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发表时间：
2020-12-01
影响因子：
2.1
通讯作者：
Ishii, Takashige
中科院分区：
文献类型：
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作者：
Amarasinghe, Yaddehige P. J.;Otsuka, Mitsuharu;Ishii, Takashige
栽培稻（Oryza sativa L.）是从亚洲野生种O.野甘草属与栽培稻相比，野生稻的小穗/种子具有长的具倒钩的芒。为了评价芒在野生稻中的作用，（全芒、半芒、四分之一芒和无芒），在模拟亚洲热带生境的自然条件下，研究了种子的传播运动：（1）种子与亲本的分离，（2）成熟种子的下落角，（3）种子滑入小空间的能力，（4）种子的萌发，（5）种子的萌发，（6）种子的萌发，（7）种子的萌发，（8）种子的萌发，（9）种子的萌发，（10）种子的萌发，（1（4）地面水平运动;（5）水中水平运动。结果表明，芒在种子传播的初始阶段能促进成熟种子从穗上脱落。它们在空中调节垂直方向，垂直的形式可以使种子挤压到地面。有芒种子在地上和水中的水平运动也显示出优势。在大多数实验中，芒满的种子表现出最好的种子传播性能，这表明野生稻保持长芒在自然条件下生存。由于种子芒在几个位点上主要受野生功能等位基因控制，野生稻可能能够防止芒长度的急剧减少。
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.