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ARS Home » Plains Area » Bushland, Texas » Conservation and Production Research Laboratory » Livestock Nutrient Management Research » Research » Publications at this Location » Publication #256956

Title: The impact of planting date on management of the rice water weevil in Louisiana rice

Author
item STOUT, MICHAEL - Louisiana State University
item HUMMEL, NATALIE - Louisiana State University
item FRY, MARTY - Louisiana State University
item Rice, William

Submitted to: The Open Entomology Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/20/2010
Publication Date: 3/10/2011
Citation: Stout, M.J., Hummel, N.A., Fry, M.J., Rice, W.C. 2011. The impact of planting date on management of the rice water weevil in Louisiana rice. The Open Entomology Journal. 5:1-9.

Interpretive Summary: The rice water weevil, Lissorhoptrus oryzophilus, is the most destructive insect pest of rice in the United States. Early planting of rice to avoid damaging infestations of the rice water weevil has long been suggested as a management tactic. A five-year study was conducted to characterize the influence of rice planting date on rice water weevil management in light of recent trends toward earlier planting of rice in Louisiana. Results from these experiments show that early planting of rice facilitated rice water weevil management in three ways. Weevil infestations were lighter in rice planted in mid- to late March than in later-planted rice in three of five years of the study. In addition, yield losses attributable to weevil feeding were lower in early planted rice than in late planted rice in the two split-plot experiments. Finally, single applications of Karate (a pyrethroid applied to rice after flooding to kill weevil adults) were less effective in late-planted rice than in early planted rice. This study demonstrates that early planting can serve as an important component of a management program for rice water weevils in Louisiana.

Technical Abstract: The rice water weevil, Lissorhoptrus oryzophilus, is the most destructive insect pest of rice in the United States. Early planting of rice to avoid damaging infestations of the rice water weevil has long been suggested as a management tactic. A five-year study was conducted to characterize the influence of rice planting date on rice water weevil management in light of recent trends toward earlier planting of rice in Louisiana. Experimental designs differed among years: experiments in 2001 and 2008 were split-plot studies, whereas experiments in 2003, 2004, and 2007 were separate randomized block experiments. Results from these experiments show that early planting of rice facilitated rice water weevil management in three ways. Weevil infestations were lighter in rice planted in mid- to late March than in later-planted rice in three of five years of the study. In addition, yield losses attributable to weevil feeding were lower in early planted rice than in late planted rice in the two split-plot experiments. Finally, single applications of Karate (a pyrethroid applied to rice after flooding to kill weevil adults) were less effective in late-planted rice than in early planted rice. This study demonstrates that early planting can serve as an important component of a management program for rice water weevils in Louisiana.