Hostname: page-component-586b7cd67f-vdxz6 Total loading time: 0 Render date: 2024-11-22T12:20:04.753Z Has data issue: false hasContentIssue false

The role of wild rice (Oryza rufipogon) awns in seed dispersal

Published online by Cambridge University Press:  21 January 2021

Yaddehige P.J. Amarasinghe
Affiliation:
Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe657-8501, Japan
Mitsuharu Otsuka
Affiliation:
Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe657-8501, Japan
Sathya Lim
Affiliation:
Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe657-8501, Japan
Ryo Ishikawa
Affiliation:
Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe657-8501, Japan
Takashige Ishii*
Affiliation:
Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai, Nada-ku, Kobe657-8501, Japan
*
Author for correspondence: Takashige Ishii, E-mail: [email protected]

Abstract

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.

Type
Research Paper
Copyright
Copyright © The Author(s), 2021. Published by Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

These authors contributed equally to this work.

References

Amarasinghe, YPJ, Kuwata, R, Nishimura, A, Phan, PDT, Ishikawa, R and Ishii, T (2020) Evaluation of domestication loci associated with awnlessness in cultivated rice, Oryza sativa. Rice 13, 26.CrossRefGoogle ScholarPubMed
Bessho-Uehara, K, Wang, DR, Furuta, T, Minami, A, Nagai, K, Gamuyao, R, Asano, K, Angles-Shim, RB, Shimizu, Y, Ayano, M, Komeda, N, Doi, K, Miura, K, Toda, Y, Kinoshita, T, Okuda, S, Higashiyama, T, Nomoto, M, Tada, Y, Shinohara, H, Matsubayashi, Y, Greenberg, A, Wu, J, Yasui, H, Yoshimura, A, Mori, H, McCouch, SR and Ashikari, M (2016) Loss of function at RAE2, a previously unidentified EPFL, is required for awnlessness in cultivated Asian rice. Proceedings of the National Academy of Sciences of the United States of America 113, 89698974.CrossRefGoogle ScholarPubMed
Chambers, JC and MacMahon, JA (1994) A day in the life of a seed: movements and fates of seeds and their implications for natural and managed systems. Annual Review of Ecology and Systematics 25, 263292.CrossRefGoogle Scholar
Elbaum, R, Zaltzman, L, Burgert, I and Fratzl, P (2007) The role of wheat awns in the seed dispersal unit. Science 316, 884886.CrossRefGoogle ScholarPubMed
Garnier, LKM and Dajoz, I (2001) Evolutionary significance of awn length variation in a clonal grass of fire-prone savannas. Ecology 82, 17201733.CrossRefGoogle Scholar
Hua, L, Wang, DR, Tan, L, Fu, Y, Liu, F, Xiao, L, Zhu, Z, Fu, Q, Sun, X, Gu, P, Cai, H, McCouch, SR and Sun, C (2015) LABA1, a domestication gene associated with long, barbed awns in wild rice. Plant Cell 27, 18751888.CrossRefGoogle ScholarPubMed
Ikemoto, M, Otsuka, M, Thanh, PT, Phan, PDT, Ishikawa, R and Ishii, T (2017) Gene interaction at seed-awning loci in the genetic background of wild rice. Genes & Genetic Systems 92, 2126.CrossRefGoogle ScholarPubMed
Ishii, T, Numaguchi, K, Miura, K, Yoshida, K, Thanh, PT, Htun, TM, Yamasaki, M, Komeda, N, Matsumoto, T, Terauchi, R, Ishikawa, R and Ashikari, M (2013) OsLG1 regulates a closed panicle trait in domesticated rice. Nature Genetics 45, 462465.CrossRefGoogle ScholarPubMed
Kulic, IM, Mani, M, Mohrbach, H, Thaokar, R and Mahadevan, L (2009) Botanical ratchets. Proceedings of the Royal Society B 276, 22432247.CrossRefGoogle ScholarPubMed
Li, C, Zhou, A and Sang, T (2006) Rice domestication by reducing shattering. Science 311, 19361939.CrossRefGoogle ScholarPubMed
Li, X, Yin, X, Yang, S, Yang, Y, Qian, M, Zhou, Y, Zhang, C, Du, Y and Yang, Y (2015) Variations in seed characteristics among and within Stipa purpurea populations on the Qinghai–Tibet Plateau. Botany 93, 651662.CrossRefGoogle Scholar
Luo, J, Liu, H, Zhou, T, Gu, B, Huang, X, Shangguan, Y, Zhu, J, Li, Y, Zhao, Y, Wang, Y, Zhao, Q, Wang, A, Wang, Z, Sang, T, Wang, Z and Han, B (2013) An-1 encodes a basic helix-loop-helix protein that regulates awn development, grain size and grain number in rice. Plant Cell 25, 33603376.CrossRefGoogle ScholarPubMed
Ntakirutimana, F, Xiao, B, Xie, W, Zhang, J, Zhang, Z, Wang, N and Yan, J (2019) Potential effects of awn length variation on seed yield and components, seed dispersal and germination performance in Siberian wildrye (Elymus sibiricus L.). Plants 8, 561.CrossRefGoogle Scholar
Oka, HI (1988) Origin of cultivated rice. Amsterdam, Elsevier.Google Scholar
Wolgemuth, CW (2009) Plant biomechanics: using shape to steal motion. Current Biology 19, 409410.CrossRefGoogle ScholarPubMed

Amarasinghe et al. supplementary material

Movie S1

Download Amarasinghe et al. supplementary material(Video)
Video 436.2 KB

Amarasinghe et al. supplementary material

Movie S2

Download Amarasinghe et al. supplementary material(Video)
Video 357.5 KB
Supplementary material: PDF

Amarasinghe et al. supplementary material

Amarasinghe et al. supplementary material 1

Download Amarasinghe et al. supplementary material(PDF)
PDF 630.3 KB