Nondestructive Estimation of Shoot Nitrogen in Different Rice Genotypes

摘要: Plant N uptake and grain yield are important components of use efficiency. Grain is easily measured, but plant analysis time consuming requires hazardous chemicals or expensive equipment. A nondestructive method involving the least equipment skill, to determine uptake, needed in agronomic breeding experiments. shoot (aboveground biomass) transplanted rice (Oryza sativa L.) was developed based on SPAD-502 chlorophyll meter readings, leaf area, tiller number. In two dry-season one wet-season field experiment, various genotypes at flowering were highly correlated (P < 0.05) with CLAT, product SPAD reading from a selected (C), area that (LA), number tillers (T) (r 2 = 0.46, 0.90, 0.85 Exp. 1, 2, 3, respectively); LAT, LA T 0.56, 0.88, 0.76). Shoot may be estimated using LAT for larger differences compared readings. Lower correlations 1 due lower range contents. The highest correlation between CLAT observed third uppermost leaf. Regressions varied across growth stages seasons. Thus, can used evaluate among fertilizer treatments different given stage within season. Further work assess reliability this under seasons cultural practices.