Assessment of genetic diversity of maize landraces in Tanzania using Random Amplified Polymorhic DNA markers

Abstract

The knowledge and comprehension of the genetic variation of maize (Zea mays L.) landraces is pivotal for the implementation of measures to address conservation and improvement. The purpose of this study was to assess the genetic diversity and relationship among selected maize genotypes in Republic of Tanzania by screening twenty Random Amplified Polymorphic DNA molecular markers.DNA was extracted from 160 maize genotypes and PCR was conducted using twelve informative primers. Amplification revealed 104 polymorphic bands with an average of 8.67 polymorphic fragments per primer. The number of amplified fragments ranged from 7 (OPP-02) to 10 (OPK-08), with the amplicon sizes ranging from 75 to 2000 base pairs. The polymorphic information content (PIC) ranged from 0.7487 to 0.954 with an average of 0.8647 and gene diversity value ranged from 0.7531 to 0.9577 with an average of 0.8698.The dendrogram drawn based on Neighbour- Joining method revealed the diversity and genetic relatedness among the landraces in the various clusters but did not reflect the geographical locations of the studied maize genotypes. This might be attributed to the high gene flow in the various study locations.The analysis of the RAPD molecular markers revealed a high genetic diversity among the maize landraces and proved to be a practical method for assessing polymorphism in maize cultivars. These findings will be useful to establish and improve the current germplasm collection of landraces and help maximize the utility of maize genetic resources.