Statistical Analysis of Foreign Rice Phenotypes under Different Seasons of the Philippines

Korean rice is a foreign genetic resources in the Philippines that has to be characterized for its proper germplasm utility. Ten Korean phenotypes were analyzed using correlation, clustering and principal component analyses (PCA) based on the 13 traits viz., culm length (CL), days to 50% flowering (D50F), days to maturity (DM), filled grains per panicle (FGP), flag leaf length (FLL), flag leaf width (FLW), grain length (GL), grain width (GW), grain yield (GY), plant height (PH), productive tillers (PT), spikelet fertility SF) and thousand grain weight (TGW) under different seasons of the Philippines. It was found out that Korean phenotypes had earlier D50F and DM, shorter PH and CL, more PT, FGP and SF, and higher GY under dry than wet season. Each season had three groups based on the clustering analysis with a pattern of group 1 having phenotypes with heavy TGW, early D50F and DM, short PH and FLL; and more FGP, SF and GY; group 2 having long CL, wide FLW, light TGW; and late D50F and DM; and group 3 having short CL, narrow FLW and low PT. Correlation in FGP, PT and SF to GY was consistently high positive (r≥0.68) in two seasons. Also, PCA consistently showed that GY, PH and PT were the highest contributor of variation with an average of 21.42% in two seasons. Korean GY therefore was highly variable but attaining higher GY can be possible by utilizing grain-filling (FGP and SF) and productive tillering (PT) traits as selection indices in the breeding program.