Root weight affects radiation-use efficiency in rice
2002
Farrell, T.C. | Williams, R.L. | Angus, J.F.
Recent studies showed that root biomass in different rice varieties can range from 2 to 5 t ha¯¹ at flowering, with less root growth generally associated with earlier flowering varieties. This chapter reports how radiation-use efficiency (RUE) is affected by whether roots are included or exluded from the calculation of biomass. In 1998, four rice cultivars of different duration were grown in replicated field experiment at the Yanco Agricultural Institute to investigate the effect of root weight and length of growing season on RUE. Plots were sampled every 2 wk from sowing to maturity to determine leaf area index, aboveground biomass, and root biomass. RUE was calculated for each plot based on two methods of expressing biomass and three time intervals. RUE for total biomass (RUET) was estimated from the relationship between total biomass (shoot plus root weight) and intercepted radiation. RUE for aboveground biomass (RUEAG) was estimated from the relationship between aboveground biomass and intercepted radiation. The three time intervals were sowing to flowering, flowering to maturity, and sowing to maturity. The longest duration variety, Amaroo, partitioned twice as much biomass to the roots as the shorter duration varieties and had the highest RUET. There were greater differences among the varieties for RUET than for RUE AG and RUET was highly correlated with increases in root weight.
Mostrar más [+] Menos [-]Palabras clave de AGROVOC
Información bibliográfica
Este registro bibliográfico ha sido proporcionado por International Rice Research Institute