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In situ gap analysis of genetic diversity of wild Coffea species from Mauritius. Ehsan Dulloo IPGRI. Coffea macrocarpa , a wild coffee relative. Overview. Background on target taxa and region Steps in Gap analysis Ecogeographic survey Genetic diversity analysis
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In situ gap analysis of genetic diversity of wild Coffea species from Mauritius Ehsan Dulloo IPGRI Coffea macrocarpa, a wild coffee relative Workshop 2: Threat and conservation assessment
Overview • Background on target taxa and region • Steps in Gap analysis • Ecogeographic survey • Genetic diversity analysis • Conservation Priorities • Lessons learnt
Background on Coffee • Important beverage world wide • Family : Rubiaceae • Sub Family: Ixoroideae • Tribe: Coffeeae • Sections: Paracoffea, Argocoffea, Mascarocoffea and Eucoffea • >100 species world wide; endemic to Africa • All species are diploid (2n=22) and outcrossing except C. arabica (allotetraploid) and is self sterile
Mascarene islands Natural Distribution of coffee species in Africa and Madagascar
Mascarenes islands • 3 Volcanic islands SW of Indian ocean- Mauritius, Reunion, Rodrigues • Uninhabited • Rich diversity of endemic plants – 955 native flowering plant taxa (73% endemic) • Mauritius- 685 natives; 311 endemics • With human colonisation-rapid deforestation
Threats • Deforestation • Land clearing for agriculture • Habitat alteration • Invasive alien species (introduced animals & plants)
Conservation history • Pioneering ecological studies in 1930’s – Native vegetation: Palm savannah, Lowland dry forest, Upland wet montane rainforest • 1950’s- Creation of protected areas- Nature Reserves • 1970s- conservation reports on Mauritius; focus on CR endemic avifauna • 1980’s – IUCN/WWF Plant programme- rescue critically endangered plants through ex situ conservation, Red data book
In situ conservation • Species Ecosystem • Establishment of Conservation Management areas within PAs • Elimination of invasives, active restoration, permanent quadrats • 1990s – Creation of first National Park on Mauritius
Coffea mauritiana Coffea macrocarpa Coffea myrtifolia Target taxa
Target Coffea taxa Coffea mauritiana Lam. • Mauritius & La Reunion endemic • Conservation status: • Mauritius: CR (B 1,2a); • La Reunion VU (C 2a) • Threats: • alien species • People picking wild fruits • Seed predation by pigs, birds • Ecology: Mid to high altitude wet montane rainforest
Target taxa • Coffea macrocarpa A. Rich • Endemic to Mauritius • Conservation status: VU (C 2a) • Threats: Aliens species, deer grazing, people picking wild fruits • Ecology: Widespread distribution in the upland climax montane rain forest to lowland moist forest and open dwarf Sideroxylon forest
Target taxa Coffea myrtifolia (A. Rich ex DC) leroy • Endemic to Mauritius • Conservation status: EN (B 1,2ciii; D) • CR – AOO <10km2 and a total population of 150 indiv. • known from at least 5 pop and one has >50 individuals • Threats: alien species, browsing by deer, habitat alteration, low genetic variability, seed predation • Ecology: Evergreen dry forest
Objective of the study Gap analysis of wild Coffea of Mauritius to ensure that genetic diversity is effectively and efficiently conserved in protected areas
Gap Analysis • Gap analysis is a method for identifying gaps in network of conservation areas. • Analysis should allow identification of hotspots which might offer efficient conservation opportunities • Allows setting of priorities • Helping in reserve selection and design
Steps in Gap analysis • Identify and classify biodiversity • Focus in on wild coffea species and the extent and distribution of its genetic diversity • Locate areas managed primarily for biodiversity • Area of occurrence within native vegetation areas and protected areas or under management • Identify biodiversity that is unrepresented in those managed areas • Compare distribution of Coffea spp. with protected areas • Set priorities for conservation actions • Recommendation for protected areas or other conservation actions
Ecogeographic survey • Purpose was to map distribution of wild Coffea spp. in the Mascarene • Herbarium survey- 248 specimen were examined • C. mauritiana: 6 localities in MRU & 25 in REU • C. macrocarpa: 18 localities • C. myrtifolia: 8 localities • Field work- based on • Herbarium survey • Information from specialists, local field workers • 26 localities were surveyed in MRU & REU • Distribution maps containing historical & actual sites
Table 1: Main herbarium collection of Mascarene Coffea taxa. (Codes from Holmgren et al. 1990)
Distribution maps of wild coffee were produced C. mauritiana
Genetic diversity studies • Purpose was • to determine the genetic relationships between coffee species and • to study the distribution of genetic diversity in wild populations and compare with existing conservation areas • Allows to define which areas have highest genetic diversity i.e. genetic hotspots areas (within population diversity) • 16 populations were studied using RAPD markers
RAPD • 20 different primers were screened • 12 produced clear and discrete bands • Of these, two primers (OPA-04 and OPI-20), were selected for the RAPD assay of all the Coffea accessions (5 indiv. per population). • 85 polymorphic bands were used for the analysis • Similarity index matrix was generated using simple matching coefficient with NTSYS-pc software to construct dendrograms using the UPGMA
Genetic analysis • 25 of 85 polymorphic bands were unique to one of the four clusters • Within population genetic diversity (Hj) is more important at looking for GD hotspots • High diversity in MDR, PCH, FLO, MDC and MLO • Low diversity in C. myrtifolia (small population sizes)
Cluster analysis • Taxonomic confirmation about three species + One cluster for MDC population • C. mauritiana: Clear distinction between accessions Mru & Reu
Gaps in protected areas • Important populations of C. macrocarpa are not located in PA – MDC, MDR, BBL • Many populations within PA are also in Conservation Management Areas • C. mauritiana: No PA in Reunion; No CMA at Plaine Champagne (Mru) • Population of C. myrtifolia are outside PA
Criteria Conservation threat highest Are not in PA and/or managed areas Populations which have high GD Socio-economic and political factors Priority Montagne des Creoles (MDC) C. myrtifolia population: Magenta C. mauritiana in Reu PCH pop in Mru Priorities for in situ conservation
Lessons learnt • Value of ecogeographic surveys • Conservation threats assessment • Value of genetic analysis and determination of genetic diversity hotspots • Helps in validating taxonomic relatedness among species • Effectiveness of protected areas • Setting up of priorities for conservation