Abstract
Rhizoctonia oryzae-sativae and R. oryzae are the causal agents of aggregate sheath spot and sheath spot of rice, respectively, in Australia. Both diseases are well distributed within the Australian rice growing area. The effects of six fungicides (metalaxyl-methyl, azoxystrobin, kresoxim-methyl, pyraclostrobin, propiconazole and toclofos-methyl) on mycelial growth of R. oryzae-sativae and R. oryzae were tested in vitro. Pyraclosotrobin and propiconazole were strong inhibitors of both pathogens and all isolates tested were sensitive to these two fungicides. Both fungicides significantly reduced disease development in field tests but failed to increase rice yield. As well, aggregate sheath spot caused yield losses as high as 20.3% and sheath spot reduced yields by up to 10%. This is the first report quantifying potential yield losses caused by aggregate sheath spot and sheath spot of rice under Australian conditions.
Similar content being viewed by others
References
Carling DE, Helm DJ, Leiner RH (1990) In vitro sensitivity of Rhizoctonia solani and other multinucleate and binucleate Rhizoctonia to selected fungicides. Plant Disease74, 860–863.
Gunnell PS (1986) Characterization of the teleomorphs of Rhizoctonia oryzae-sativae, Rhizoctonia oryzae, and Rhizoctonia zeae. and the effect of cultural practices on aggregate sheath spot of rice, caused by R. oryzae-sativa. PhD Thesis, University of California, Davis, USA.
Gunnell PS (1992) Aggregate sheath spot. In ‘Compendium of rice diseases’. (Eds RK Webster, PS Gunnell) pp. 23–24. (APS Press: St Paul, MN, USA)
Gunnell PS, Webster RK (1984) Aggregate sheath spot of rice in California. Plant Disease68, 529–531.
Inagaki K, Tamura M, Makino M (1987) Overwintering in plant residues of rice sclerotial disease fungi, Rhizoctonia and Sclerotium species. Proceedings of the Kansai Plant Protection Society29, 27–29.
Lanoiselet VM, Ash GJ, Cother EJ, Priest MJ, Watson A (2001) First report of Waitea circinata causing sheath spot and Rhizoctonia oryzae-sativae causing aggregate sheath spot of rice in Australia. Australasian Plantt Pathology30, 369–370. doi: 10.1071/AP01053
Martin SB, Campbell CL, Lucas LT (1984a) Comparative sensitivity of Rhizoctonia solani and Rhizoctonia-like fungi to selected fungicides in vitro. Phytopathology74, 778–781.
Martin SB, Campbell CL, Lucas LT (1984b) Response of Rhizoctonia blights of tall fescue to selected fungicides in the glasshouse. Phytopathology74, 782–785.
Miller TC, Webster RK (2001) Soil sampling techniques for determining the effect of cultural practices on Rhizoctonia oryzae-sativae inoculum in rice field soils. Plant Disease85, 967–972.
Mordue JEM (1974) ‘Rhizoctonia oryzae-sativae. CMI Description of Pathogenic Fungi and Bacteria No. 409’. (Commonwealth Mycological Institute: Kew, UK)
Ou SH (1985) ‘Rice diseases.’ 2nd edn. (Commonwealth Mycological Institute: Kew, UK)
Rush MC (1992) Sheath spot. In ‘Compendium office diseases’. (Eds RK Webster, PS Gunnell) pp. 23–24. (APS Press: StPaul, MN,USA)
Van der Hoeven EP, Bollen GJ (1980) Effect of benomyl on soil fungi associated with rye. 1. Effect on the incidence of sharp eyespot caused by Rhizoctonia cerealis. Netherlands Journal of Plant Pathology86, 163–180.
Yoshimura S (1954) On the scale for estimating degree of severity of sheath blight by Hypochus sasakii Shirai in rice plants. Annals of the Phytopathological Society of Japan9, 58–60.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Lanoiselet, V.L., Cother, E.J., AshA, G.J. et al. Yield loss in rice caused by Rhizoctonia oryzae and R. oryzae-sativae in Australia. Australasian Plant Pathology 34, 175–179 (2005). https://doi.org/10.1071/AP05013
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1071/AP05013