A blog maintained by Tevita Kete, PGR Officer
Secretariat of the Pacific Community (SPC), Suva, Fiji Islands
This weblog documents the activities of Pacific Agricultural Genetic Resources Network (PAPGREN), along with other information on plant genetic resources (PGR) in the Pacific.
The myriad varieties found within cultivated plants are fundamental to the present and future productivity of agriculture. PAPGREN, which is coordinated by the Land Resources Division of the Secretariat of the Pacific Community (SPC), helps Pacific countries and territories to conserve their crop genetic diversity sustainably, with technical assistance from the Bioversity International (BI) and support from NZAID and ACIAR.
SPC also hosts the Centre of Pacific Crops and Trees (CEPaCT). The CEPaCT maintains regional in vitro collections of crops important to the Pacific and carries out research on tissue culture technology. The CEPaCT Adviser is Dr Mary Taylor (MaryT@spc.int), the CEPaCT Curator is Ms Valerie Tuia (ValerieT@spc.int).
PAPGREN coordination and support
Mr William Wigmore
Mr Adelino S. Lorens
Dr Lois Englberger
Mr Apisai Ucuboi
Dr Maurice Wong
Mr Tianeti Beenna Ioane
Mr Frederick Muller
Mr Herman Francisco
Ms Rosa Kambuou
Ms Laisene Samuelu
Mr Jimi Saelea
Mr Tony Jansen
Mr Finao Pole
Mr Frazer Bule Lehi
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Wednesday, March 02, 2005
Posted 6:41 PM by Luigi
Warm water prevents nematodes in yams
The following article appeared in a newspaper, so the details of the science may have been reported incorrectly, as 100 C seems quite hot actually! Any comments?
New Vision (Kampala), February 23, 2005
RESEARCHERS at Namulonge Agricultural Animal Research Institute (NAARI) have advised farmers to dip their yam seeds in warm water before planting to avert nematodes from attacking their crop.
Hot water treatment is a new preventive measure where yam seeds are placed in warm treated water of approximately 100 C before planting.
Nematodes are one of the delicate and dangerous diseases which attack yams. The disease recently invaded the districts of Kayunga, Luweero, Nakasongola and Mukono and destroyed different plants.
"This preventive measure is still new and we have started sensitising farmers about it. Nematodes are very dangerous yam pests. They destroy the plant and it dries up completely," says James Rwebikile, the Clean Yam Project focal person in charge of Kayunga district. He said the disease mainly spreads during the dry season.
Yam is a traditional food in Uganda, which is mostly eaten when there is food shortage because of its resistance to drought.
Hot water treatment for banana and yam planting material
Yes, hot water treatment really works for banana and yam planting material. Some years ago, while working in Ghana, we applied hot water to yam planting material with good results. But 100 oC is definitely too hot!
Yam planting material is immersed in warm water of approx. 53-55 oC for 20 minutes. A locally fabricated steel tank of about one cubic meter is used for the treatment, using propane gas as heating source. This kills the nematodes in the tissue without negatively affecting the germination of the planting material. The treated planting material should be planted in new farmland, or land where other crops have been grown for one or two years to ensure that the nematode population in the soil is low.
Subject: Re: PGR News from the Pacific: Warm water prevents nematodes in yamsPost a Comment
Hot water treatment for yam nematodes has been about for some time (from mid-'70s at least), but is rather difficult for farmers to use successfully. There's a fairly narrow margin, in terms of both temperature and time of treatment, between killing the nematodes and killing the seed sett. In yams, "seed" means quite a large piece of tuber, and obviously adding these to water drops the temperature of the water. Treatments I have seen reported use around 48oC, which is much harder to monitor than 100oC (you can see if it's boiling!). More recently, some promising results have been obtained by dipping in household disinfectant solutions (Dettol or bleach), and these are much easier to handle. Dave Hutton, at the University of the West Indies, Jamaica, has been the main researcher in this area. See:
Hutton, D.G. 1999 Use of household disinfectants to suppress Pratylenchus coffeae and dry rot of yellow yam (Dioscorea cayenensis). Tropical Agriculture 75(2): 49-52
Agrobiodiversity Weblog: For discussions of conservation and sustainable use of the genetic resources of crops, livestock and their wild relatives.