ANALYSIS OF PHENOTYPIC DIVERSITY OF SELECTED HEVEA ACCESSIONS FROM IRRDB 1981 GERMPLASM COLLECTION CONSERVED IN SRI LANKA

Abstract

Present study was undertaken to estimate morphological diversity of some accessions from IRRDB 1981 Hevea germplasm collection conserved in Sri Lanka to determine the importance of morphological descriptors in categorizing different accessions in to discrete groups. 13 accessions and clone RRISL 203 were characterized using 14 standardized morphological descriptors. Principal Component Analysis (PCA) showed that the all descriptors were informative and contributes significantly to the variation. First 6 Principal Component scores (PCs) accounted for 88% of the total variation. The cluster analysis based on significant PCs grouped all accessions and RRISL 203 in to 4 main clusters at the distance of 1. Four accessions had more than 1 RMS distance, representing a higher phenotypic variation. RRISL 203 has showed lowest distance (0.12). This study permits the characterization of Hevea accessions in to phenotypically diverse groups using morphological descriptors; hence this will be advantageous for production of diverse genotypes during breeding programs to broaden the Hevea gene pool.

Keywords: Hevea germplasm, morphological descriptors, phenotypic variation