Journal of Nematology (2005) 37, 386-387

A. Ortiz, B.S. Sipes, J. Cho, J.Y. Uchida and S. Miyasaka (2005)
Sustainable control of soilborne pathogens in dryland taro
Journal of Nematology 37 (3), 386-387
44th Annual Meeting, Society of Nematologists, Fort Lauderdale, Florida, 9-13 July, 2005
Abstract: Taro (Colocasia esculenta) germplasm collections Thaipalm and Cho 2000 totaling 54 accessions, were screened for resistance, tolerance and susceptibility to Meloidogyne javanica a major pathogen of taro grown in dryland cropping systems. Susceptibility was observed in the germplasm, with nematode reproduction factors (Rf) in the range of 1.3 - 84.58. Resistance to M. javanica may be present within C. esculenta. Cultivars which hold promise as poor hosts to M. javanica include Thailand #259, Nepal # CL83027, Thailand #6, Thailand #164, Thailand #2, GXH #173, HXP #140, SXP #171 and IXPNG #18. Susceptibility of 10 green manure crops to M. javanica were evaluated. Green manure species were selected based on known inhibitory compounds toward soil-borne pathogens. Host susceptibility and biomass production of green manure crops were assayed. Marigolds, and sorghum X Sudan grass hybrids were poor hosts to M. javanica, with Rf values ranging from 0 to 0.61. The sorghum X Sudan grass hybrids produced the greatest amounts of biomass, averaging 5.2 g dry weight/plant. The interactive effects between M. javanica and a Pythium sp. on seven Tagetes, four Brassica, seven sorghum X sudan grass, and four other green manure crops were evaluated. The Brassica spp. and four of the marigold cultivars were killed by the combined infections. Sunn hemp and all of the sorghum X Sudan grass cultivars were unaffected by either pathogen. The sorghum X Sudan grass cultivars continued to yield the highest biomass. Sorghum X Sudan grass was a poor host to M. javanica, produced copious biomass, and is an excellent green manure candidate for use in dryland taro cropping systems. In conjunction with resistant varieties, green manures are an important component of a sustainable program to control soil-borne pathogens. This research provides necessary information to develop a sustainable method to control soil-borne pathogens in dryland taro cropping systems.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Database assignments for author(s): Brent S. Sipes, Janice Y. Uchida

Research topic(s) for pests/diseases/weeds:
resistance/tolerance/defence of host

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Meloidogyne javanica	Taro (Colocasia)	U.S.A. (Hawaii)