Onwughalu J.T., Abo M.E., Okoro J.K., Onasanya A., Sere Y.
Department of Crop and Environmental Protection, University of Agriculture, Makurdi, Nigeria; National Cereals Research Institute Badeggi, University of Agriculture, P.M.B. 8, Bida, Nigeria; Plant Pathology Unit, Africa Rice Center (AfricaRice), 01 BP 203
Onwughalu, J.T., Department of Crop and Environmental Protection, University of Agriculture, Makurdi, Nigeria; Abo, M.E., National Cereals Research Institute Badeggi, University of Agriculture, P.M.B. 8, Bida, Nigeria; Okoro, J.K., Department of Crop and Environmental Protection, University of Agriculture, Makurdi, Nigeria; Onasanya, A., Plant Pathology Unit, Africa Rice Center (AfricaRice), 01 BP 2031, Cotonou, Benin Republic, Nigeria; Sere, Y., Plant Pathology Unit, Africa Rice Center (AfricaRice), 01 BP 2031, Cotonou, Benin Republic, Nigeria
The study on the resistance of Gigante, Moroberekan and Bouake 189 rice varieties was investigated against the Rice yellow mottle virus (RYMV) infection relative to time of infection under screenhouse controlled condition. Rice varieties, Moroberekan, Gigante and Bouake 189, were inoculated with RYMV isolate at seedling, tillering, booting and flowering growth stages. Gigante, Moroberekan and Bouake 189 gave mean yield losses of 12.68, 78.06 and 94.4%, respectively at booting and seedling infection stages. The No. of grains plant-1 is mostly affected at booting infection stage in Bouake 189 and at seedling infection stage in Moroberekan. No significant difference in No. of empty spikelets plant-1 due to infection at different growth stages among the three varieties. Plant height was significantly affected by virus infection at seedling stage of the three varieties and other growth stages of Bouake 189. The highest yield loss of 94.4% obtained in Bouake 189 at seedling and booting infection stages establishes the fact that yield losses to RYMV are strongly influenced by host cultivars as well as time of virus infection. The study revealed that the period from seedling and booting represents the most vulnerable phase to RYMV infection in rice growth stages. This information would strongly assist breeding programmes in the development of durable resistant rice cultivars to RYMV disease. © 2010 Asian Network for Scientific Information.