Yield loss caused by Meloidogyne graminicola on lowland rainfed rice in Bangladesh

The impact of Meloidogyne graminicola on growth and yield of lowland rainfed rice was assessed with and without carbofuran in a rice-wheat rotation area of northwestern Bangladesh. The experiment was conducted on farmer fields and at a research station, with experimental plots arranged in a randomized complete block design. Prior to transplanting, rice seedling height and dry weight were greater (P less than or equal to 0.05) and soil levels of M. graminicola were lower (P less than or equal to 0.05) in the treated seedbed plots compared to the nontreated control plots. Nematicide application to the field at transplanting had a greater effect (P less than or equal to 0.05) on mid-season plant growth than did nematicide application to the seedbed at sowing, and rice yield increased by 1.0 t/ha where carbofuran was applied to the seedbed and field-both at the research station (P less than or equal to 0.05) and on farmer fields (P less than or equal to 0.10)-compared to a nontreated control. This is the first report of a negative impact of M. graminicola on growth and yield of lowland rainfed rice in production fields in Bangladesh.