Interference Durations of Bearded Sprangletop (Leptochloa fascicularis) in Rice (Oryza sativa)

Abstract
Effects of bearded sprangletop interference durations on Lemont and Newbonnet rice cultivars were studied. Interference durations of 63, 70, and 130 d after rice emergence reduced Lemont grain yields 11, 21, and 50%, respectively, and lowered Newbonnet grain yields 11, 13, and 37%, respectively. Interference durations of 21 to 56 d after emergence did not reduce grain yields of either cultivar. Bearded sprangletop grown in Lemont rice produced more biomass than that in Newbonnet. Season-long interference reduced plant height and straw dry weight of Lemont more than that of Newbonnet.