Heat can make a difference: production of disease-free banana seed
RTB researchers have shown that heat treatment can be a cost-effective tool for controlling disease transmission in banana and plantain.
In partnership with the Colombian Plantain Growers Federation (FEDEPLATANO) scientists at CIAT standardized a prototype of a thermotherapy chamber for propagating clean planting material that has proven to be effective and adaptable. Plantain corms are placed in a chamber to sprout under controlled conditions of temperature (50º-70ºC) and high humidity, with frequent fertigation, producing healthy seedlings faster than traditional methods.
The technology was further validated by Bioversity plant pathologist Miguel Dita, who built a prototype chamber at the Center for Tropical Agricultural Research and Higher Education, in Costa Rica, and has since been adopted by organizations in several countries. FEDEPLATANO and CIAT built a large thermal chamber in La Tebaida Quindío, Colombia that produces disease-free plantain planting material for approximately 7,000 farmers. CIAT also collaborated with the Brazilian Agricultural Research Corporation for the construction of another large, fully automated chamber for plantain farmers in Northeast Brazil.
“Larger thermal chambers are an efficient option for the mass production of clean seed for farmer associations,” explained CIAT researcher Elizabeth Alvarez. “However, the technology has also been successfully adapted for smaller scale operations.”
Alvarez cited the example of simplified thermal chambers built by farmers in El Salvador. With technical assistance from CIAT and FEDEPLATANO, and support from the NGOs Oxfam, Caritas and Catholic Relief Services, farmer associations in the department of Morazán built tunnel-formed chambers using translucent plastic sheets and other inexpensive materials that now produce clean banana seed for about 1,650 smallholders, 350 of who are women.
CIAT has promoted the technology with manuals in Spanish and English via the Latin America and Caribbean (LAC) banana network and has collaborated with CIRAD to promote it as a way to control the banana and plantain disease Moko bacterial wilt in LAC. The technology has also been tested in Peru, and there are plans to evaluate it in Ecuador, Nicaragua, Panama, Cameroon and DR Congo.
Meanwhile IITA researchers have validated an even simpler thermotherapy option for cleaning banana and plantain suckers of nematodes. IITA researcher Stefan Hauser explained that farmers merely need to dip suckers into boiling water for 30 seconds prior to planting to kill nematodes, adding that research has demonstrated that this practice improves yields. IITA has promoted the boiling water method to African banana and plantain farmers through a manual and flyers in multiple languages, and demonstrations for more than 1,000 farmers in Cameroon, Nigeria and Zanzibar.
Alvarez noted that CIAT has also promoted thermotherapy to combat the spread of cassava frogskin disease, with thermal chambers a various sizes for producing clean cassava planting material built in several departments of Colombia, Brazil, Costa Rica and Paraguay. She added that the technology could likely be adapted for other crops as well.