Browsing by Author "Sserumaga, J.P."

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    Genetic characterisation of Ugandan strains of Colletotrichum sublineolum using ISSR makers
    (African Journals Online (AJOL), 2013) Sserumaga, J.P.; Biruma, M.; Akwero, A.; Okori, P.; Edema R.
    Colletotrichum sublineolum, the causal agent of sorghum anthracnose, presents high variability, genetic instability and host specialisation, hence rapidly breaking down resistance. In Uganda, no population studies of Colletotrichum sublineolum have been reported hence there is limited information on the nature of epidemics and pathogen. The present study aims at investigating the genetic diversity within 124 Colletotrichum sublineolum isolates from Uganda. The intersimple sequence repeats (ISSR) produced 37 polymorphic loci and neighbor-joining analysis revealed two major groups. There were no major groups among all isolates in studies. Analysis of molecular variation (AMOVA) based on 7 agro-ecologies of Uganda revealed the presence of a population structure, (FFST = 0.08 P = 0.05) leading to acceptance of null hypothesis stating a presence of population differentiation between the agro-ecologies in Uganda. Gene flow between agro-ecologies was 5.75 calculated from ÔFST. The results of the AMOVA analysis revealed the allelic variation (92.5%) was shared between populations. Average gene diversity over all loci ranged from 0.192 to 0.335 showing high diversity within population rather than between populations. The numbers of polymorphic loci were similar for the population studied.
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    Genetic Diversity among Tropical Provitamin A Maize Inbred Lines and Implications for a Biofortification Program
    (Cereal research communications, 2019) Sserumaga, J.P.; Makumbi, D.; Warburton, M.L.; Opiyo, S.O.; Asea, G.; Muwonge, A.; Kasozi, C.L.
    Insights into the diversity and relationships among elite breeding materials are an important component in maize improvement programs. We genotyped 63 inbred lines bred for high levels of provitamin A using 137 single nucleotide polymorphism markers. A total of 272 alleles were detected with gene diversity of 0.36. Average genetic distance was 0.36 with 56% of the pairs of lines having between 0.30 and 0.40. Eighty-six percent of the pairs of lines showed relative kinship values <0.50, which indicated that the majority of these provitamin A inbred lines were unique. Relationship pattern and population structure analysis revealed presence of seven major groups with good agreement with Neighbour Joining clustering and somewhat correlated with pedigree and breeding origin. Utilization of this set of provitamin A lines in a new biofortification program will be aided by information from both molecular-based grouping and pedigree analysis. The results should guide breeders in selecting parents for hybrid formation and testing as a short-term objective, and parents with diverse alleles for new breeding starts as a long-term objective in a provitamin A breeding program.