Coconut (Cocos nucifera L.) is considered the most important crop along the coastal belt of West Africa. It provides food and income for many women and landless poor and requires minimal capital outlay. Côte d’Ivoire ranks in the top among the 92 coconut-producing countries (FAO, 2012). It is the top Africa exporter of coconut oil, which accounts for 2.5% of the world vegetable oil production. In Côte d’Ivoire, coconut is cultivated on approximately 50,000 hectares (1 to 5 ha/farmer), and produces around 45,000 tons of copra/year. It is the main income source for the coastal region (Allou et al, 2012).
Lethal Yellowing (LY)-type phytoplasma diseases pose the major threat for the global coconut industry. Over the past ten years, Côte d’Ivoire Lethal Yellowing disease (CILY) has destroyed over 350 ha and caused losses of 12,000 tons of copra/year in Ivorian coastal areas (ProMED, 2013). The causality was unknown until Canadian and Ivorian scientists linked a CILY outbreak, currently involving over 7000 ha in the Grand-Lahou region, with the Ghana Cape St. Paul Wilt (CSPW) phytoplasma strain that has destroyed about one million Ghanaian coconuts in the last 30 years (Konan et al, 2013). The findings strengthened suspicions that the disease had spread from neighbouring Ghana. Phytoplasmas are unculturable insect-transmitted plan pathogens that have devastated diverse crops worldwide and have only been partially studied through DNA-based methods (Duduk & Bertaccini, 2011; Strauss, 2009).
CILY has impacted farmers’ own family nutrition, as women are not able to feed livestock or obtain nutritious milk and water produced within coconuts. Farmers may be forced to market reduced amounts and drop prices for seed nuts and coconut-derived products. Women may have insufficient income to provide food, schooling and clothing for children. Moreover, soil erosion due to loss of trees has prevented crop diversification that might yield alternative cash and food sources.
LY-type phytoplasma palm diseases have been extensively studied not just in Ghana (Yankey et at, 2009, 2011) but also in Tanzania, where disease annihilated 56% of the southern palms in the last 30 years (Mpunami et al, 2000), and in Nigeria where Awak disease killed over 98% of the West African Tall Palms in 2006 (Odewale et at, 2010). However, no information is available in Côte d’Ivoire, the host of the multi-site International coconut Genebank for Africa and the Indian Ocean. The Asian and Pacific Coconut Community has strongly recommended strengthening studies on the LY-type phytoplasma in countries hosting International Coconut Genebanks (COCOMMUNITY Newsletter, 2011). Canadian and Ivorian partners have integrated field and laboratory studies and capacity building aimed at alleviated CILY phytoplasma problems and improving livelihoods of impoverished coconut communities.
This proposal responds to the current CILY situation, focusing on perspectives and needs of farmers (particularly women). Plans include characterizing the CILY agent, identifying vector(s) and secondary plan host(s) to improve disease management, conducting epidemiology studies and developing new diagnostics for rapid field detection in support of quarantine surveillance and germplasm certification. No effective control has yet been identified other than replanting with resistant/tolerant varieties to secure a sustainable industry (CFC, 2005). Project outcomes will include supplying cultivars resistant to local CILY phytoplasma strains, and assisting breeding programs. LY-type phytoplasmas may be transmitted through seed, so investigations will be undertaken to help authorities make decisions on germplasm movement (Cordove et al, 2003; Nipah et at, 2007). Project outcomes will include the identification of bacterial endosymbionts that reduce vector competence, as well as endophytic fungi and bacteria in CILY-affected coconuts that may enhance plant resilience and promotes long-term biological control strategies (Bulgari et al, 2012; Gonelle et al, 2011; Musetti et al, 2011). Capacity building activities will be coordinated among authorities, policy makers, stakeholders and farmers, especially women, so that useful developments can be disseminated effectively, improving livelihoods of coconut smallholder farmers in coastal Côte d’Ivoire.