Abstract:
Breeding new varieties adaptable for changing climate is an essential need in sustainable
rice production. Around 2000 Sri Lankan rice accessions at Plant Genetic Resources Centre
(PGRC), Sri Lanka have not been fully characterized for the yield potential and sensitivity to
mild photoperiodic differences for days to flowering (DF). DF is a candidate key determinant
in yield components in rice and understanding the physiological and molecular nature for DF
is important to manipulate crop yield through breeding programmes. The objective of this study
was to assess the genetic diversity of 15 Hondarawala accessions from PGRC using selected 37
morphological characters and DF. DF varied from 58-189 days while accession number 3988
did not flower until 200th day of seed germination. Principal Component Analysis (PCA) revealed
that four principle components (PA) explained 86.5% of total observed variation. Variation of
DF positively associated with most of morphological characters of vegetative growth while a few
characters were negatively associated. In the dendogram, 10 clusters formed at rescale distance
of 5. Widely variable DF accessions distributed among clusters.
