Genetic Characterization of Alupe Napier Grass Accessions Based on Simple Sequence Repeat Markers
Geofrey Kawube *
National Crops Resources Research Institute, National Agriculture Research Organisation, P.O.Box 7084, Kampala, Uganda and Faculty of Agriculture and Environment, Gulu University, P.O.Box, 166, Gulu, Uganda
Jolly Kabirizi
National Livestock Resources Research Institute, National Agriculture Research Organisation, P.O.Box 96, Tororo, Uganda
Clementine Namazzi
National Livestock Resources Research Institute, National Agriculture Research Organisation, P.O.Box 96, Tororo, Uganda.
*Author to whom correspondence should be addressed.
Abstract
Genetic variability of 23 Napier grass clones, 22 of which were collected from Kenya Agricultural Research Institute – at Alupe in Kenya was determined using 17 simple sequence repeat (SSR) markers. All markers were polymorphic with the most discriminative being PSMP2267. Average gene diversity among the Napier grass clones was 0.54 with an average heterozygosity of 0.63. Total number of alleles across all loci was 90 with mean number of alleles per locus of 5.29 and a mean polymorphic information content of 0.50. Results also indicate a high genetic distance among the Napier grass clones with the most distant clone being 16814 while the closest was between kakamega1 and kakamega2 and kakamega2 and kakamega3. Principal Co-ordinates Analysis did not group the clones in a definitive structure, with most clones scattered. However, the SSR markers grouped the clones into two clusters derived from a dendogram generated by Neighbour joining analysis with clone 16814 being alone in a cluster. Clone Kakamega1, Kakamega2 and Kakamega3 as very closely related. These findings are key in guiding selection of clones for inclusion in breeding programs and conservation of Napier grass.
Keywords: Genetic diversity, genetic relationships, Pennisetum pupureum, population structure- simple sequence repeats transferability