A review of research on the effects of drought and temperature stress and increased CO2 on Theobroma cacao L., and the role of genetic diversity to address climate change

The global status of research on the effects of drought, temperature and elevated carbon dioxide (CO2) levels on the cacao plant, and the role of genetic diversity in producing more resilient cacao, are presented in this report. With the aim to enhance what we know about the resilience of cacao to climate change, and generate a comprehensive understanding of the questions that remain, this report highlights significant advances in published and ongoing research on drought and temperature tolerance in cacao.

Most of the information about ongoing or unpublished work was obtained from personal communications and surveys involving research institutes around the globe. Organizations were selected to participate in the survey based on their presence in the relevant literature, referrals from other organizations, or personal communications from individuals attesting to their involvement in research related to drought and temperature tolerance, or increased CO2 response, in cacao. A vast network of public and private sector partners including research institutes, producer organizations, and industry representatives around the world participated and were involved to collect additional information on unpublished and on-going research work in this area.

Over 100 scientists from 50 institutes across 29 countries participated. Additional information was gathered from personal communications, surveys carried out in collaboration with WCF and its USAID-supported Feed the Future Partnership for the Climate-Smart Cocoa Program, the Global Network for Cacao Genetic Resources (CacaoNet), the International Network for Cacao Genetic Improvement (INGENIC), the Regional Breeders Working Groups, and the research team on cacao and climate change at the University of Reading, UK. Fundamentally, the literature compiled in this report serves as a basis to understand the questions that still remain regarding cacao’s responses to abiotic stresses, highlight the resources that are available to answer them, and identify synergies and complementarities.

The report also helps to identify key research questions and partners for the development of a proposal for an international/multi-institutional research programme, to be implemented over the next three to five years, as part of the Collaborative Framework for Cacao Evaluation (CFCE). Although future climatic predictions are worrisome, the genetic materials held within national and international collections offer much potential in the development of improved planting material. The objective of the report is to gather as much information as possible, so that we can aim to maximize the resilience of cacao through the discovery and use of improved planting material, in combination with improved management practices.

The authors express gratitude to all of those who provided details of thier research on cacao genetic resources and abiotic stress and acknowledge financial support of WCF and its Feed the Future Partnership for Climate Smart Cocoa, through a grant to Bioversity International from USDA-FAS, the ECA/CAOBISCO/FCC Joint Working Group on Cocoa Quality and Productivity; and the CGIAR Research Program on Forests, Trees and Agroforestry (FTA).

Author(s): Medina, V.; Laliberte B.

Year: 2017

Copyright 2017 @ CGIAR Research Program - Forests, Trees and Agroforestry