Cultivar differences of aboveground rice (Oryza sativa L.) plant morphology and their correlation with yield
The objectives of this paper were to examine cultivar differences of aboveground rice plant morphology and structure at the early tillering stage, and analyze its potential correlations with yield. The 4 rice cultivars, Liangyou108 (hybrid long-grain rice, V1), 86You8 (hybrid round-grain rice, V2), Nanjing43 (round-grain rice, V3), and Yangtao6 (long-grain rice, V4), were grown in field. Their rice plant morphology and structure (RPMS) parameters and yield were measured. The 1st, 2nd, and 3rd leaf blade length, width, and bowstring length on the main stem, and the 1st leaf sheath length, tangent angle, and bowstring angle (between blade and main stem) among 4 cultivars at the 3rd or 4th maximum blade length period on the main stem all had significant differences (P<0.01). The 1st leaf sheath length at the 4th maximum blade length period on the main stem had high positive correlation with yield, with significant (r=0.96) in 2007 at p<0.05, and the 1st maximum blade width on the main stem at the 3rd maximum blade length period on the main stem was negatively correlated with yield, with significant (r= −0.99) in 2008at p<0.05. These results provided an initial scientific basis for using morphological and structural parameters for forecasting early yield potential and selecting characters of plant morphological types for high yielding.