Effect of different doses of fungicide bentazole combl 50 % SL on the growth of fungus nurses rhizactonia solani and fusarium solani isolated from cucumber plant

Abstract EN

The study aimed to test the effect of repeated treatment with a different dose of the fungicide Bentazole Combl 50% SL on the appearance of pesticides resistance in pathogenic fungi Rhizactonia solani and Fusarium solani.

Pthogenicity tests showed that both Rhizactonia solani and Fusarium solani are pathogenic on radish seeds with infection rates of 100 and 90%, respectively.

In case of R.solani, Bentazole Combl 50% SL affected the fungal radial growth, where the lowest radial growth in the treatment of double dose of Bentazole Combl 50% SL compared to the control (6.72 and 0.00) cm respectively, for the first transfer.

While, the lowest radial growth appeared in the treatment of the full dose Bentazole Combl 50% SL compared to the control treatment reaching 1.03 cm and 8.15 cm, respectively, for the second transfer.

As for F.solani, the highest radial growth (2.60 cm) occurred in the control treatment and the lowest radial growth (0.00 cm) occurred in the treatment of double dose of Bentazole Combl 50% SL for the first transfer, while in the second transfer, the highest radial growth occurred in the control treatment (4.46 cm) and the lowest radial growth occurred in the treatment of double dose Bentazole Combl 50% SL (0.6 cm).

Similar results were obtained where both fungi grown on the liquid medium (PDB) based on the fresh and dry weight of fungal biomass.

Generally, both fungi R.

solani and F.

solani showed an ability to tolerate and resist the tested fungicide especially when used at lower concentration than the recommended dose.