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Unusually High Frequency of Cross-Pollination Between Rice Landraces Shiuli and Kharah with Coincident Flower-Opening Times


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1 Centre for Interdisciplinary Studies, 186A Kalikapur Canal Road, Kolkata 700 099, India
 

Cross-pollination in cultivated rice (Oryza sativa L.) is rarely reported to exceed 2%. This low cross-pollination frequency (CPF) is conducive to success-fully maintaining the purity of rice landraces for many generations. We were therefore surprised to notice a dramatic loss of genetic purity in some of the pure line landraces in many farmers’ fields. Having ruled out the possibility of mixing of seeds from dif-ferent varieties, we surmised this rapid loss of genetic purity to be due to a somewhat higher degree of cross-pollination, and conducted a carefully designed expe-riment with suitably chosen pairs of landraces. We report here an unusually high (>81%) CPF seen in a pair of landraces whose flower opening times (FOTs) were coincident. Our control experiment on a pair of landraces with non-overlapping FOTs failed to detect any cross-pollination. This preliminary report sug-gests that the crucial importance of FOT diversity in landraces in determining CPF has not been recognized in designs of previous reports of crossing experiments, resulting in a severe underestimation of CPF in cultivated rice under natural conditions.

Keywords

Cross-Pollination Frequency, Flower Opening and Closing Times, Genetic Purity, Pollen Viability, Rice Landraces.
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  • Endo, T., Sato, H., Yamaguchi, M., Kataoka, T., Nakagomi, K., Ito, T. and Mori, K., Estimate of outcrossing rates in a rice plant (Oryza sativa L.) under field conditions using a purple grain rice cultivar, Okunomurasiki. Breed. Sci., 2009, 59, 195–202.
  • da Silva, E. F., da Silva, L. M. and Montalván, R., Crossing rate and distance in upland rice. Bragantia, 2005, 64(2), 197–201.
  • Reaño, R. and Pham, J. L., Does cross-pollination occur during seed regeneration at the International Rice Genebank? Intern. Rice Res. Notes, 1998, 23, 5–6.
  • Jodon, N. E., Occurrence and importance of natural crossing in rice. Rice J., 1959, 62(8), 8–10.
  • Robert, E. H., Craufurd, R. Q. and Cochet, F. L., Estimation of percentage of natural cross-pollination: experiment on rice. Nature, 1961, 190, 1084–1085.
  • Sahadevan, P. C. and Namboodiri, K. M. N., Natural crossing in rice. Proc. Indian Acad. Sci., Sect. B, 1963, 58, 176–185.
  • Beachell, H. M., Adair, C. R., Jodon, N. E., Davis, L. L. and Jones, J. W., Extent of natural crossing in rice. J. Am. Soc. Agron, 1938, 30, 743–653.
  • Coste, R., El Arroz: Colección Agricultura Tropical, Editorial Blume, Barcelona, Spain, 1969, 2nd edn, pp. 35–72.
  • Somaratne, L. H. M. Y. K., Abayawickrama, A. S. M. T., Wickramasinghe, I. P. and Samarasinghe, W. L. G., Estimating outcrossing rate of Bg 379-2 using morphological markers and confirmation by molecular markers. Rice Sci., 2012, 19(2), 166–168.
  • Messeguer, J., Fogher, C., Guiderdoni, E., Marfà, V., Català, M. M., Baldi, G. and Melé, E., Field assessments of gene flow from transgenic to cultivated rice Oryza sativa L. using a herbicide resistance gene as tracer marker. Theor. Appl. Genet., 2001, 103, 1151–1159.
  • Messeguer, J., Marfà, V., Català, M. M., Guiderdoni, E. and Melé, E. A., Field study of pollen-mediated gene flow from Mediterranean GM rice to conventional rice and the red rice weed. Mol. Breed., 2004, 13, 103–112.
  • Rong, J. et al., Dramatic reduction of crop-to-crop gene flow within a short distance from transgenic rice fields. New Phytol., 2007, 173, 346–353.
  • Bae, H.-K. et al., Evaluation of gene flow from GM to non-GM rice. Plant Breed. Biotech., 2013, 1(2), 162–170.
  • Langevin, S. A., Clay, K. and Grace, J. B., The incidence and effect of hybridization between cultivated rice and its related weed red rice (Oryza sativa L.). Evolution, 1990, 44, 1000–1008.
  • Song, Z. P., Lu, B.-R., Zhu, Y. G. and Chen, J. K., Gene flow from cultivated rice to the wild species Oryza rufipogon under experimental field conditions. New Phytol., 2003, 157, 657–665.
  • Wang, F. et al., A large-scale field study of transgene flow from cultivated rice (Oryza sativa) to common wild rice (O. rufipogon) and barnyard grass (Echinochloa crus-galli). Plant Biotechnol. J., 2006, 4, 667–676.
  • Moldenhauer, K. A. K. and Gibbons, J. H., Rice morphology and development. In Rice: Origin, History, Technology and Production (eds Smith, C. W. and Dilday, R. H.), Wiley, Hoboken, NJ, USA, 2003, pp. 103–127.
  • OGTR, The Biology and Ecology of Rice (Oryza sativa L.) in Australia, Office of the Gene Technology Regulator, Woden, Australia, 2005.
  • Deb, D., Flowering asynchrony can maintain genetic purity in rice landraces. Curr. Sci., 2006, 91, 155–157.
  • GoI, Biology of Oryza sativa L. (Rice), Department of Biotechnology, Ministry of Science and Technology, and Ministry of Environment and Forests, Government of India, 2011; http://biosafety.icar.gov.in/biology-of-oryza-sativa-l-rice
  • Kobayasi, K., Masui, H., Atsuta, Y., Matsui, T., Yoshimoto, M. and Hasegawa, T., Flower opening time in rice –cultivar difference and effect of weather factors. In Proceedings of MARCO Symposium 2009: challenges for Agro-Environmental Research in monsoon Asia, (CD-ROM), National Institute for Agro-Environmental Sciences, Tsukuba, Japan, 2009.
  • Kobayasi, K., Matsui, T., Yoshimoto, M. and Hasegawa, T., Effects of temperature, solar radiation, and vapor-pressure deficit on flower opening time in rice. Plant Prod. Sci., 2010, 13(1), 21–28.
  • Bioversity International, International Rice Res. Institute and the Africa Rice Center. Descriptors for Wild and Cultivated Rice (Oryza spp.) Bioversity International, Rome, Italy, 2007.

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  • Unusually High Frequency of Cross-Pollination Between Rice Landraces Shiuli and Kharah with Coincident Flower-Opening Times

Abstract Views: 375  |  PDF Views: 131

Authors

Debal Deb
Centre for Interdisciplinary Studies, 186A Kalikapur Canal Road, Kolkata 700 099, India
D. Bhattacharya
Centre for Interdisciplinary Studies, 186A Kalikapur Canal Road, Kolkata 700 099, India

Abstract


Cross-pollination in cultivated rice (Oryza sativa L.) is rarely reported to exceed 2%. This low cross-pollination frequency (CPF) is conducive to success-fully maintaining the purity of rice landraces for many generations. We were therefore surprised to notice a dramatic loss of genetic purity in some of the pure line landraces in many farmers’ fields. Having ruled out the possibility of mixing of seeds from dif-ferent varieties, we surmised this rapid loss of genetic purity to be due to a somewhat higher degree of cross-pollination, and conducted a carefully designed expe-riment with suitably chosen pairs of landraces. We report here an unusually high (>81%) CPF seen in a pair of landraces whose flower opening times (FOTs) were coincident. Our control experiment on a pair of landraces with non-overlapping FOTs failed to detect any cross-pollination. This preliminary report sug-gests that the crucial importance of FOT diversity in landraces in determining CPF has not been recognized in designs of previous reports of crossing experiments, resulting in a severe underestimation of CPF in cultivated rice under natural conditions.

Keywords


Cross-Pollination Frequency, Flower Opening and Closing Times, Genetic Purity, Pollen Viability, Rice Landraces.

References





DOI: https://doi.org/10.18520/cs%2Fv121%2Fi1%2F121-126