Assessment of Genetic Variability Among Selective Guava (Psidium Guajava L.) Varieties by RAPD Analysis

Abstract

This study was conducted to assess the genetic diversity using random amplified polymorphic DNA (RAPD) variation of twelve varieties of guava (Psidium guajava L.) growing in southern part of Bangladesh. Morphological characterization of guava varieties showed a wide range of variation. Highest variability was observed in Poly and Jelly varieties. DNA was extracted from twelve guava varieties by using modified CTAB method and was quantified by mini-gel method for RAPD analysis. RAPD analysis was carried out and only unambiguous, reproducible and scorable polymorphic fragments were taken into consideration for analysis. Polymerase chain reaction (PCR) with 5 arbitrary 10-mer and 5 arbitrary 12-mer oligonucleotide primers produced a total of 50 bands of which 75.23 percent were polymorphic. The highest percentage of polymorphic loci (100%) was observed for primer A and the lowest (50%) was for A03 primer. The UPGMA dendrogram revealed the segregation pattern and the difference of evolutionary changes from origin for each variety. Guava varieties were separated into two main groups, one of them was made up Chinese, Jelly, Kazi, Apple, L-49 and Local-2. The other one was made up Local-1, Local-3, Poly, Kashi, Thai and Bombay. The range of genetic distance was observed 0.2054 (Apple and Kazi) to 0.7837(Bombay and Local-3). The highest genetic distance 0.784 including Apple and Kazi derived from different origin and could be utilized in breeding programme for improving trait of interest. This scientific information could be used for further improvement of guava genotypes through breeding program.