Hostname: page-component-cd9895bd7-gxg78 Total loading time: 0 Render date: 2024-12-27T10:11:31.115Z Has data issue: false hasContentIssue false

Mechanisms of competition for light between rice (Oryza sativa) and redstem (Ammannia spp.)

Published online by Cambridge University Press:  12 June 2017

Theodore C. Foin
Affiliation:
Department of Environmental Studies, University of California, Davis, CA 95616
James E. Hill
Affiliation:
Department of Agronomy, University of California, Davis, CA 95616

Abstract

Redstem is an important weed in California water-seeded rice fields because of its aquatic habit, wide distribution, interference with harvest, and resistance to the herbicide bensulfuron. Our objective was to understand the mechanisms of competition for light between rice and redstem, with the goal of improving redstem control. A replicated greenhouse experiment was done in 1993 and 1994. Rice was water-seeded at a rate of 400 seeds m−2, and redstem was seeded simultaneously at approximate densities of 0, 50, and 100 seeds m−2 in continuously flooded 0.77 m2 basins. Plants were harvested once at final harvest in 1993 and twice in 1994, with an additional nondestructive sampling 34 days after seeding (DAS). Despite slower early growth, redstem height exceeded rice height about 45 DAS. At the midseason harvest in 1994 (56 DAS), no effects of redstem competition on any rice response variables were detected. However, at final harvest (110 and 118 DAS, 1993 and 1994, respectively) redstem competition at both treatment densities reduced rice tiller density, panicle density, shoot drymass, and grain drymass. Redstem competition reduced rice growth only after penetrating the canopy. Shade cast by redstem through rice maturity decreased shoot and grain production and increased tiller mortality. Lodging caused by redstem further affected rice growth. Season-long competition from redstem at mean densities of 67 and 110 plants m−2 reduced rough rice yields 31 and 39%, respectively, making redstem the most competitive broadleaved rice weed yet studied. Improved understanding of rice-redstem interactions indicates that using alternative herbicides to bensulfuron is unlikely to increase yield losses to redstem, and that control may be improved by increasing rice plant densities or slightly delaying early season chemical control. Because these strategies are mechanistic, they may also be useful for controlling other rice weeds with growth patterns similar to redstem.

Type
Weed Biology and Ecology
Copyright
Copyright © 1997 by the Weed Science Society of America 

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.)

References

Literature Cited

Ballaré, C. L. 1994. Light gaps: sensing the light opportunities in highly dynamic canopy environments. in Caldwell, M. M. and Pearcy, R. W., eds. Exploitation of Environmental Heterogeneity by Plants: Ecophysiological Processes Above- and Belowground. San Diego, CA: Academic Press, pp. 73110.Google Scholar
Barnes, P. W., Maggard, S., Holman, S. R., and Vergara, B. S. 1993. Intraspecific variation in sensitivity to UV-B radiation in rice. Crop Sci. 33: 10411046.CrossRefGoogle Scholar
Barrett, S. C. H. and Seaman, D. E. 1980. The weed flora of Californian rice fields. Aquat Bot 9: 351376.Google Scholar
Bayer, D. E. and Hill, J. E. 1992. Weeds. in Flint, M. L., ed. Integrated Pest Management for Rice. University of Calif. Statewide Integrated Pest Management Project, Publication 3280. Oakland, CA: University of California, pp. 3255.Google Scholar
Breen, J. L. 1995. The design, parameterization and validation of CAN-WER, a model to simulate biomass development, shading, tillering, and yield of direct-seeded rice in competition with broadleaf weeds. Ph.D. thesis. University of California, Davis, CA. 233 p.Google Scholar
Caton, B. P., Foin, T. C., and Hill, J. E. 1996. Phenotypic plasticity of redstem (Ammannia spp.) in competition with rice. Weed Res. In press.CrossRefGoogle Scholar
Doyle, C. J. 1991. Mathematical models in weed management. Crop Prot. 10: 432444.Google Scholar
Firbank, L. G. and Watkinson, A. R. 1986. Modeling the population dynamics of an arable weed and its effects upon crop yield. J. Appl. Ecol. 23: 147–59.Google Scholar
Graham, S. A. 1979. The origin of Ammannia X coccinnea Rottboell. Taxon 28: 169178.Google Scholar
Harper, J. L. 1964. The individual in the population. J. Ecol. 59: 149158.Google Scholar
Hill, J. E., Bayer, D. E., Bocchi, S., and Clampett, W. S. 1991. Directseeded rice in the temperate climates of Australia, Italy, and the United States. in Direct-Seeded Flooded Rice in the Tropics. Manila, Philippines: International Rice Research Institute, pp. 91102.Google Scholar
Hill, J. E., DeDatta, S. K., and Real, J. G. 1989. Echinochloa competition in rice: a comparison of studies from direct-seeded and transplanted flooded rice. in Auld, B. A., Umaly, R. C., and Tjitrosomo, S. S., eds. Proceedings of the Symposium on Weed Management. Bogor, Indonesia: Southeast Asian Regional Centre for Tropical Biology, pp. 115129.Google Scholar
Hill, J. E., Smith, R. J. Jr., and Bayer, D. E. 1994. Rice weed control: current technology and emerging issues in the United States. in Proceedings of the Temperate Rice Conference. New South Wales, Australia: Yanco, pp. 377391.Google Scholar
Kropff, M. J. 1993a. Ecophysiological models for crop-weed competition. in Kropff, M. J. and van Laar, H. H., eds. Modeling Crop-Weed Interactions. Wallingford, U.K.: CAB International, pp. 2532.Google Scholar
Kropff, M. J. 1993b. General introduction. in Kropff, M. J. and van Laar, H. H., eds. Modeling Crop-Weed Interactions. Wallingford, U.K.: CAB International, pp. 17.Google Scholar
LeStrange, M. 1981. Competition between rice (Oryza sativa) and Barnyardgrass (Echinochloa spp.): the influence of rice stature, barnyardgrass density, and nitrogen fertility. M.S. thesis. University of California, Davis, CA. 124 p.Google Scholar
Little, T. M., and Hills, F. J. 1978. Agricultural Experimentation. New York: J. Wiley, pp. 132133.Google Scholar
Miller, B. C., Hill, J. E., and Roberts, S. R. 1991. Plant population effects on growth and yield in water-seeded rice. Agron. J. 83: 291297.Google Scholar
Neter, J., Wasserman, W., and Kutner, M. H. 1990. Applied Linear Statistical Models. 3rd ed. Boston, MA: R. D. Irwin, pp. 349411 614-621, 642–647.Google Scholar
Norris, R. F. 1992. Have ecological and biological studies improved weed control strategies? in Proceedings of the First International Weed Control Congress. Melbourne, Australia: Weed Sci. Soc. of Victoria, pp. 733.Google Scholar
Pappas-Fader, T. J., Turner, R. G., Cook, J. F., Butler, T., Lana, P. J., and Carriere, M. C. 1993. Resistance monitoring program for aquatic weeds to sulfonylurea herbicides in California rice fields. in Proceedings of the Twenty-Fifth Rice Technical Working Group. College Station, TX: Texas A&M University System, p. 65.Google Scholar
Sánchez, R. A., Casal, J. J., Ballaré, C. L., and Scopel, A. L. 1993. Plant responses to canopy density mediated by photomorphogenic processes. in International Crop Science I. Madison, WI: Crop Science Society of America, pp. 779786.Google Scholar
Smith, R. J. Jr. 1988. Weed thresholds in Southern U.S. rice, Oryza sativa . Weed Technol. 2: 232241.Google Scholar