Effect of red rice interference in fourth densities of commercial rice

Field trials were carried out in The Regional Research Grain Station “Sur del Jíbaro”, Sancti Spíritus, in order to study the infestation effect of 0, 12, 25, 50, 100 and 200 red rice plants per square meter (m2) on growth and yields of commercial variety J-104, seeded at 50, 100, 200 and 300 plants/m². Yield of J-104 rice variety decreased with the increase in red rice density. Crop yield decrease in the dry season ranged from 10.7 to 94.8% with infestations of 12 and 200 red rice plants /m², respectively; while in the wet season changed from 11.4 to 91.5 % with similar level in infestations. In both seasons 12 red rice plants were enough to cause a significant reduction in commercial rice yields in relation to the control treatment (without red rice infestation). The lost in crop yield was due to the decreased in panicles/ m² and filled grains per panicle, caused by the interference with red rice.