Abstract

GARCES FIALLOS, Felipe Rafael; WORDELL FILHO, João Américo  and  STADNIK, Marciel João. Effect of the Ulva fasciata extract on Pseudocercospora griseola in bean crops. Cienc. Tecnol. Agropecuaria [online]. 2020, vol.21, n.3, e1138.  Epub Aug 31, 2020. ISSN 0122-8706.  https://doi.org/10.21930/rcta.vol22_num1_art:1138.

Angular leaf spot is one of the most common diseases in beans crops in southern Brazil. This research aims to evaluate the effect of the extract from macroalga Ulva fasciata on angular leaf spot severity, foliar pigment content, and yield of common bean genotypes IPR Uirapuru, CF 22, and Mouro graúdo for 2005 and 2006. Plants were sprayed at phenological stages V3, V5, R6, and R7 with the alga extract or fungicide azoxystrobin. Untreated plants served as controls. Disease severity (%) was estimated from the V3 stage, totaling six examinations a year. Severity values were integrated as the area under the disease progress curve (AUDPC). Foliar pigments (chlorophyll a, b, total, and carotenoids) were determined in 2006. Grain yield was evaluated in both years, but the thousand-grain weight in 2005 only. The control exerted by the U. fasciata extract on angular leaf spot depends on the biological interaction between the bean genotype and the environment. The efficiency of U. fasciata extract in controlling angular leaf spot depended on the interaction between bean genotypes and the environment. Besides, the extract did not affect leaf pigment content or grain yield.

Keywords : alga extract; alternative control; angular leaf spot; foliar pigments; Phaseolus vulgaris.

        · abstract in Spanish     · text in English | Spanish     · English ( pdf ) | Spanish ( pdf )