Chemical control of anthrachnose of Sansevieria trisfasciata var. Hahnii on a detached-leaf system.

摘要

The objective of this work was to assess fungicides to combat Sansevieria trifasciata var. Hahnii anthracnose. Twelve fungicides (alone or in mixture) were evaluated on the infection and severity of C. sansevieriae on a detached- leaf system. Fungicides used were azoxystrobin, boscalid + pyraclostrobin, carbendazim + mancozeb, difenoconazole, epoxiconazole + carbendazim, folpet, imazalil, thiophanate-methyl + mancozeb, myclobutanil, and prochloraz. The study was carried out at the Plant Biotechnology Laboratory of the Agricultural Research Center of the University of Costa Rica, during the first semester of 2012. Each chemical treatment was applied by aspersion on the day of inoculation (0 dai) or three days after it (3 dai). The number and diameter of the lesions were evaluated after seven, eleven and fifteen dai. Fungicide, application moment, fungicide x application moment interaction and fungicide x evaluation moment interaction significantly affected (p<0,0001) both evaluated variables. Azoxystrobin, boscalid + pyraclostrobin, carbendazim + mancozeb, epoxiconazole + carbendazim and thiophanate-methyl + mancozeb provided 100% protection to Sansevieria leaves throughout the evaluation period (15 days) when applied the same day of inoculation (0 dai). After three days of inoculation (3 dai) only epoxiconazole + carbendazim completely inhibited the pathogen establishment (zero incidence) in the three evaluations when applied azoxystrobin and carbendazim + mancozeb, the incidence was 0% after seven and eleven days for the first treatment and after seven days for the second one.