Effect of Planting Season on Yields of Eight Short-Grain Varieties of Rice Under Irrigation

Abstract

The productivity of eight short grain varieties of rice planted every 3 months over a one-year period was determined under irrigation at Gurabo, at 80 m of elevation and mean annual temperature of 26.7° C and 1,524 mm of annual rainfall. Caloro and Colusa varieties from California had the lowest average yields for the year and were outyielded by the Spanish varieties Girona, Bahía, and Amposta, which produced 6,160 kg/ha of unhulled rice. All varieties had similar yields in September and December plantings. Amposta, Dosel, and Giron a were the highest yielders in March plantings, and Amposta, Balilla, Bahía, Girona, and Nano Sollana in June planting. September plantings produced the lowest average yields (4,581 kg/ha) of unhulled rice and June planting the highest (7,045 kg/ha). Average yield for all varieties and all seasons was 5,678 kg/ha of unhulled rice. Time required to produce a crop varied from 81 days for June planting to 117 days for December planting. Results show that three high yielding plantings of these varieties can be grown yearly in similar areas in Puerto Rico when irrigation is available.