Ocorrência de podridões em variedades de cana-de-açúcar cultivadas na Paraíba – PB.

Abstract

Sugar cane represents one of the main crops of Brazilian economy, being the most produced agricultural product in the state of Paraíba. However, limiting factors, such as the occurrence of pests and diseases that may affect the crop cause damage to producers. Among the numerous pests that attack the sugar cane cultivation in the northeast region, particularly in the state of Paraíba, are the common borer (Diatraea spp.) and to the spittlebug sugar cane (Mahanarva posticata). For the sugarcane borer leaves openings (holes and galleries) that allow entry of fungus Colletotrichum falcatum and Fusarium moniliforme causing decay that reverses the sucrose, decreasing the purity of the broth. Thus the objective of this study was to conduct a survey of the occurrence of decay in five varieties (RB 86 3129, RB 86 7515, RB 92 579, RB 931003, RB 00 2754) of sugar cane planted in Paraíba. Was the indirect isolation of fungi of the tissues by removing small fragments of the margins of superficial lesions, followed by superficial disinfestation, plating on agar-agar culture Batata-Dextrose plus antibiotic. The plates were maintained at a temperature of approximately 27°C, during seven days, followed by identification with the aid of an optical microscope. Through the technique of indirect isolation and microscopic evaluation, it was found that the causative agent of the disease belongs to the genus Fusarium, and this was detected in all the varieties analyzed, not demonstrating resistance to this pathogen.