Fungicides cytotoxicity expressed in male gametophyte development in Brassica campestris after in vitro application of converted field doses.

A simple method to determine the toxicity of fungicides on male gametophyte in Brassica campestris subsp. oleiferae is described. The calculation of fungicide concentration used in the test is derived from doses used in field application. The expression of regression curves and calculation of regression equations require the logarithmic transformation of fungicide concentration. The range of the sensitivity of the method is very wide. The minimal concentration detected as significantly different from control ranges from 1.7 to 7.0 pg of the active compound. Fungicides declared as non-toxic for plants in field tests were cytotoxic for male gametophyte development. The synergistic action of more than one active compound resulted in higher toxicity.