Avaliação de perdas causadas por Oebalus spp. (hemiptera: pentatomidae) em arroz de terras altas

Abstract

To determine the effect of Oebalus poecilus and O. ypsilongriseus on grain yield and quality of five upland rice cultivars, isolated panicles were subjected to four levels of infestation (number of adult insects): zero (control treatment), two O. poecilus, two O. ypsilongriseus and one O. poecilus plus one O. ypsilongriseus. Neither the treatments nor the interaction of the treatments with cultivars had significant effects on percentages of weight loss and empty spikelets. Insect activity, evaluated by the presence of feeding sheaths in the spikelets, demonstrated that O. ypsilongriseus was more active than O. poecilus. Plant vigor was also affected differently according to insect species; however, no differences were observed in grain amylose content. Insect infestation reduced total grain milling yield and increased the number of damaged spikelets but did not alter the percentage of whole kernels.