ACROTHECIUM LEAF SPOT OF BASELLA RUBRA L.

Abstract

A leaf spot of Basella rubra L., caused by an Acrothecium species, not previously recognized in Puerto Rico nor probably elsewhere as a parasite of the above mentioned plant, is described in this paper. The parasite was found to produce leaf lesions within 5 to 7 days after inoculation with conidia obtained from pure cultures of the organism. Vine lesions were somewhat delayed in their appearance. Humid atmospheric condition accompanied by relatively high temperature, favored the incidence of the disease, as shown by pathogenicity tests conducted under glass house and field conditions. The foliage of heavily infected plants blighted in humid environment and became useless for consumption. Weekly sprayings with Bordeaux, 3-3-50 and 4-4-50, were found successful in controlling the disease, the latter formula giving better results under persistent humid conditions of the environment.