World Cocoa Foundation Research Update: September 2007
Robert D. Lumsden, Plant Pathologist and WCF Scientific Advisor
RESEARCH GROUPS: Cacao agroforestry systems in Brazil. The USDA/ARS Sustainable Perennial Crops Laboratory (SPCL) in Beltsville, Maryland is collaborating with the State University of Santa Cruz, Bahia, Brazil on many areas of sustainable cacao production. This collaboration has resulted in the successful funding from the Dutch Buffer Stock (450,000 euros) to carry out research on "Improving the Efficiency of Cacao Agroforestry Systems in Bahia, Brazil." (Dutch Buffer Stock is a fund created by the Dutch Ministry of Agriculture, Nature and Food Quality to promote the sustainable development of the cocoa sector.) This funding will help to assess the impact of cocoa production within the cabruca production system (agroforestry) of the Brazilian Atlantic Rain Forest to improve ecosystem sustainability. Dr. Virupax Baligar of SPCL has been invited by the State University of Santa Cruz to serve on the Oversight Committee for this project.
Update from the Cacao Germplasm Collections at CATIE, Costa Rica and CRU, Trinidad, funded by WCF, with progress on the Germplasm Fingerprinting Project. The two International Cacao Germplasm Collections are extremely important to the cacao research community as resources for valuable cacao germplasm needed to improve yield through improved pest and disease resistance and agronomic characteristics as well as improved quality and flavor. They are the basis for the Bioversity initiative to establish CacaoNet. These collections have been undergoing careful review for proper identification and elimination of redundancy and mislabeled accessions. Dapeng Zhang, dapeng.zhang@ars.usda.gov, ARS, USDA, Beltsville, Maryland leads up the fingerprinting project and provided the following update on the status of the characterization of these two cacao collections.
CRU, Trinidad Collection [ICG,T]
All of the “original trees” in CRU (mostly from Marper Farm), except a few rootstocks and some CRU breeding progenies, have been genotyped. Identity checking (duplicate identification and assignment testing) has been performed. Diversity analysis is still ongoing. Using the established “reference” DNA profile to check mislabeling in the ICG,T (the field genebank in La Reunion Estate) was started in 2006.
CATIE Collection, Costa Rica
All accessions (one tree per accession) have been genotyped. Forty synonymous groups, including 152 accessions, have been identified. Diversity assessment has been performed. The result has been sent back to the CATIE collaborators. Manuscript has been submitted for journal publication. Verification was started for morphological and agronomical variation within each synonymous group identified by DNA fingerprints. This work has started and has been supported by CATIE, USDA and the Vavilov-Frankel Fellowship supported by Bioversity International.
CATIE Report from Wilbert Phillips, wphillip@catie.ac.cr , C.A.T.I.E., Turrialba, Costa Rica.“Selection and generation of moniliasis-resistant cacao genotypes and maintencnce and conservation of theInternational Cacao Collection.:” Reporting period from January to June 2007.
Establishment of New Field Trials and Clonal Gardens The most outstanding activity initiated this year was the establishment of a mother clonal garden in Turrialba which will supply the propagating material for 30 hectares of clonal gardens and 6 hectares of breeding trials in Central America. This is part of a joint effort between CATIE, NORAD and different institutions and farmer organizations to improve cacao production in six countries in the region. Six clones will be released for farmers’ use, which were selected from field trials due to their good performance in terms of moniliasis [frosty pod rot] resistance, yield and quality. The clones are the first tangible products of the breeding program which highlights the importance of the collaboration between CATIE and the World Cocoa Foundation during the last decade.
Maintenance and Routine Evaluation of the Field Trials The following agronomic practices were performed in the new and old experimental areas: establishment or maintenance of shade species; pruning of the cacao trees, weed and ant control; cleaning of the drainage system; fertilizer application; substitution of dead cacao plants with new seedlings; maintenance of the fence protecting the experimental area, etc. Evaluations of trunk diameter, first flowering and first fruiting were made in all trials. Monthly evaluations of yield and disease incidence were recorded on a tree-by-tree basis.
Artificial Determination of the Reaction to Major Diseases Artificial inoculation methods developed at CATIE were employed to evaluate the reaction to the fungi Moniliophthora roreri and Phytophthora palmivora of clones from the international germplasm collection and trees from different field trials. Thus, 1,207 and 1,783 pods were inoculated with spores of M. roreri and P. palmivora in 12 and 22 different events, respectively.
Activities Related to Germplasm Conservation, Introduction and Use The main agronomic practices carried out in the old and new sections of the International Collection. An intensive introduction of strategic germplasm from different institutions into the International Collection has been carried out during the last years as part of CATIE’s effort to enrich the genetic diversity of the international collection. During the first semester of 2007, 53 clones of T. cacao were introduced from Honduran Agricultural Research Foundation (FHIA) and Reading University. Different clones were transferred to private companies for commercial use. Some resistant clones to frosty pod rot were sent to the Intermediate Quarantine Station at Reading, UK. Vegetative material for different studies was supplied to the US Department of Agriculture Some of our best selections were sent to FHIA, Honduras to establish a clonal garden there under the framework of the new Central American Cacao Project.
CRU Report from David Butler, d.butler@tstt.net.tt; cru@cabelnett.net, Cocoa Research Unit (C.R.U.), University of the West Indies. “Evaluation of cocoa germplasm for resistance to witches’ broom disease.” Reporting period from January to June, 2007.
A total of 24 cacao clones were tested and analysed for resistance to witches’ broom. Of these, 12 showed potential resistance to witches’ broom disease and were selected for future confirmation screening. A further 16 promising clones were evaluated to confirm and quantify their resistance; and five of those were selected with confirmed resistance.
Confirmation of resistance During this reporting period, 16 clones were analysed for broom-base diameter and incubation period to show symptoms. For five clones, symptoms took longer than 20 days after inoculation to develop and did not differ significantly from the resistant control, IMC 6.
In the case of broom-base diameter, the differences among the tested clones were highly significant, and both the resistant and susceptible control showed the smallest and largest broom sizes respectively. However only two clones, CRU56 and NA824, were significantly different from the susceptible control, UF11, and these were selected as having resistance to witches’ broom disease.
When the five clones selected based on incubation period were compared with broom-base diameter data, three of the clones, LV17[POU], MOQ3/8 and NA111 were not significantly different from IMC6 and were therefore also selected as showing resistance. The five selected clones are CRU56, NA824, LV17[POU], NA111 and MOQ3/8. During the next six months, screening will focus on confirmation screening. Pods from 53 selected promising clones have been collected and beans sown in preparation for testing.
RESEARCH ON THE WEB: Nestle campaigns for benefits of dark chocolate By Karen Willmer 9/4/2007- A new Nestle-backed campaign in Australia is promoting the health benefits of dark chocolate to doctors, dieticians and nutritionists. The Switch To Dark campaign highlights recent research that indicates dark chocolate has high levels of antioxidants, and aims to encourage people to switch from milk to dark chocolate. The dark chocolate phenomenon has already been picked up by the food industry, with many manufacturers launching or focussing ondeveloping lines. Nestle has already announced it will launch a new range of dark chocolate products.Mars, Barry Callebaut and Lindt have also released their own ranges to take advantage of this new consumer fad. Full article.
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