Sensibilidad in vitro de tres agentes fúngicos en Rubus glaucus Benth y cuatro agentes fúngicos en Opuntia ficus indica L. a fungicidas de diferentes modos de acción.

Abstract

This present investigation aimed to determine the in vitro sensitivity to Fusarium oxysporum, Fusarium redolens, Fusarium solani on Rubus glaucus Benth, and the genera Geotrichum sp., Alternaria sp., Fusarium sp., Epicoccum sp. on Opuntia ficus indica L. to fungicides of different modes of action. Seven active ingredients were used such as azoxystrobin, boscalid, thyme plant extract, methyl thiophanate, copper salts, tebuconazole and thiabendazole. The stock solution was obtained from an initial concentration of the fungicide, then, serial dilutions were made to reach the established concentrations of 0.01 to 100 ppm, in the next stage, amended medium was prepared and discs with fungal mycelium were transferred, the growth was noted until the Petri dish was filled. For the statistical analysis, the R Studio program was used, and the Mycelial Growth Rate (MCR) and Effective Dose 50 (DE50) for each active principle were gotten. The results obtained on blackberry were: azoxystrobin (DE50: 52.99-31.46 ppm), boscalid (DE50: 189.83-117.17 ppm), thyme plant extract (DE50: 118.19-46.04 ppm), methyl thiophanate (DE50: 63.93-0.43 ppm), copper salts (DE50: 5.73- 5.27 ppm), tebuconazole (DE50: 1.19-0.05 ppm) and thiabendazole (DE50: 4.45-1.70 ppm; likewise in prickly pear were: azoxystrobin (DE50: 7537.61-0.92 ppm), boscalid (DE50: 265.94-0.27 ppm), thyme plant extract (DE50: 550.43-29.95 ppm), methyl thiophanate (DE50: 8330.51-0.15 ppm), copper salts (DE50: 106.05-2.94 ppm), tebuconazole (DE50: 7.63-0.17 ppm) and thiabendazole (DE50: 121.69-0.06 ppm). It is concluded that the efficient active ingredients on MCT were tebuconazole and thiabendazole for the control of Fusarium sp. in blackberry, and in prickly pear the efficient active ingredients were tebuconazole, thiabendazole and boscalid. It is recommended to apply tebuconazole for the control of Fusarium sp. in blackberry crop, and to apply tebuconazole, thiabendazole and methyl thiophanate for the control of fungi in prickly pear crop.