Microsatellite (SSR) Analysis on Genetic Diversity of (Coffea canephora) Germplasm in Kagera Region, Tanzania

Coffea canephora (Robusta) is one of the two important coffee species grown in Tanzania for commercial purpose. Robusta coffee contributes 40 - 50% of the total coffee production in Tanzania. However, the production of Robusta coffee in Tanzania has been hampered by coffee wilt disease. Despites the importance of Robusta coffee in Tanzania, its genome has not thoroughly researched. A study was conducted to investigate the molecular diversity of cultivated and wild coffee found in Kagera region in Tanzania. One hundred twenty four genotypes (124) of cultivated and wild coffee were analyzed by simple sequence repeat (SSR) marker techniques using 12 microsatellite markers. Genetic diversity, similarity or dissimilarity, genetic distances between individuals and genetic differentiation between populations was analyzed. Findings indicate high genetic variations among cultivated and wild coffee genotypes ranging between 20 and 83%. Polymorphism was 80% among SSR markers with 8 loci. Two distinctive genetic groups were identified. The first genetic group comprised four distinctive genetic groups one to four. The second genetic group consisted of four genetic groups, five to eight. Wild coffee genotypes had similarities to some of cultivated C. canephora in groups one to four implying that some cultivated C. canephora originates from wild coffee. Groups’ five to eight comprise genotypes from cultivated C. canephora . Detailed study is needed to compare the identified eight (8) genetic groups of C. canephora in Kagera region in Tanzania with the already know groups worldwide.