Efectividad Biológica de TCMTB para el Control de la Costra Negra Rhizoctonia solani Kühn de la Papa Solanum Tuberosum L., en la Región de León, Guanajuato, México

Abstract

During the 1988 summer-fall growing cycle in the Mexican region of Leon, Guanajuato the fungicide 2-(Thiocyanomethylthio) benzothiazole (TCMTB) was evaluated applying it at the rate of 6, 8 and 10 liters per hectare for the control of soil borne Black Scurf R. solani. A randomized block design with four reps was used. An evaluation was made of the following: emerged stems, phytotoxical damage, percentage of damaged shoots and stems by R. solani, yield and tuber quality; finally, percentage of R. solani damaged tuber and percentage of tubers with over 5% of damage inflicted by R. solani. It was found that no phytotoxic effect of fungicide to the potato crop was observed; that any of the fungicides comprising treatments protected the plant shoots; that no statistic differences were found among treatments pertaining tuber yield; finally the rates 8.0 and 10.0 l/ha of TCMTB and 5.0 kg/ha of pencycuron produced 27, 20 y 25 percentage of tubers with over 5% of damage inflicted by R. solani, propitiated the highest potato quality when reducing R. solani damage to tubers.