THE PHYTOTOXICITY OF DISINFECTANTS AND THEIR EFFECT AT DIFFERENT TEMPERATURES

When disinfecting plastic growth containers, only sodium hypochloride (NaClO) caused damage both to cucumber and lettuce seedlings grown on peat if the containers had not been washed with water after disinfection. Also the seedlings grown on rockwool cubes were susceptible to Menno-Ter-forte when the growth containers were not properly rinsed after disinfection. All tested disinfectants caused damage to cucumber, lettuce and cauliflower seedlings when mixed in the peat substrate. The efficiency of disinfectants was higher at +20-degrees-C than at +5-degrees-C, especially against Fusarium culmorum, F. oxysporum and Rhizoctonia solani. A decrease in temperature affected least the efficacy of NaOCl and Menno-Ter-forte and most that of Virkon S.