Efecto del acolchado con polietileno sobre micoflora asociada a un cultivo de frijol

Abstract

THE EFFECT OF PLYETHYLENE MULCH ON FUNGI IN ESTABLISHED BEAN CULTIVAR BAYO ALTEÑO WAS EVALUATED IN ZAPOPAN, JALISCO, DURING THE SPRING-SUMMER CYCLE OF 1987. THE SIX SURVEYED PLOTS INCLUDED ROWS TREATED WITH BLACK AND TRASNPARENT POLYETHYLENE OF 200 THICK AND NO-MULCH CONTROL ROWS. THE FUNGI POPULATION OF SOIL AND ROOT WAS ANALYZED PLACING THE SAMPLES ON POTATO DEXTROSE AGAR PLATES CONTAINING ROSE BENGAL AND LACTOC ACID. AT 0-15 CM DEPTH, BOTH TREATMENTS SHOWED NO QUANTITATIVE EFFECT ON THE AVERAGE OF TOTAL COLONIES, AS MUCH AS THAT ACHIVED ON THE ROOTS OF TREATED PLANTS. COVERING SOIL WITH POLYETHYLENE SHEETS RESULTED IN 100% CONTROL OF RHIZOCTONIA SOLANI AND 71-100% OF SCLEROTIUM ROLFSII. AT THE SAME DEPTH, WHERE PATHOGENS WERE LOCATED THERE WERE INCREASES IN THE NUMBER OF COLONIES  OF GLIOCLADIUM SP. IN 100% WITH BOTH PLASTIC FILMS AND TRICHODERMA SP. IN 22% AND 39% WITH BLACK AND TRANSPARENT POLYETHYLENE, RESPECTIVELY; THESE FUNGI HAVE BEEN REPORTED AS ANTAGONISTIC TO SOILBORNE PATHOGENS. THE RESULTS SHOW THAT WHEN A MULCH IS PRESENT DURING THE GROWING SEASON, SOILBORNE BEAN PESTS CONTROL CAN BE EXPECTED.