The biological evaluation of Zato 50 WG in protection of carrot against Alternaria blight.

Effectiveness of new fungicide Zato 50 WG (biologically active substances BAS - trifloxystrobin 50%) in the control of Alternaria blight on carrot was studied. Field experiments were carried out in the years 2003-2004 on carrot cv. Koral. As the standard fungicide Amistar 250 SC (BAS - azoxystrobin 250 g/dm3) was used. The results of health status of carrot leaves analysis in first and second year of experiment showed, that development of disease symptoms was lower on leaves of chemical protected plants than on leaves of control plants. The last estimation of infestation degree of carrot leaves made immediately before harvest showed, that standard fungicide Amistar had longer systemic influence on plants. This was confirmed the lower (statistically significant) infestation index of protected carrot in combination with Amistar. The estimations of health status of carrot roots were made directly after digging up indicate, that there wasn't difference of value of infestation index between protected combination and control. Experiment showed, significant effect of tested fungicides on crop quantity of carrot roots per 1 m2. Especially in the second year of study the crop of carrot roots in combination with Zato was higher - statistically significant - than in the rest combinations.