All-India Coordinated Rice Improvement Project, Rajendra Nagar, Hyderabad-500 030.
Several rice varieties (104) with a broad spectrum of duration for flowering ranging from 70–125 days were considered for working out the relationships between biomass, harvest index (HI) and economic yield. Crop duration did not show any relationship with HI. Increased duration was found to be associated with higher biomass but higher biomass was not related to higher HI. A positive relationship was found between biomass and grain yield and between HI and economic yield. The importance at higher HI in association with higher biomass was emphasized. The plants were classified into low and high HI ones. Nitrogen and spacing did not influence HI considerably. The importance of HI and biomass as criteria for identifying donors and the significance of HI as a selection criterion is discussed.
