The effects of treatments with selected pesticides on viability and vigour of maize (Zea mays) seeds and seedling emergence in the presence of Fusarium graminearum

摘要

The quality of seed is dependent on two very broad aspects: how healthy (disease-free) a seed is and its fieldperformance (germination and vigour). The objective of the present study was to evaluate the effect of pesticidalseed treatments of maize (Zea mays L.) on seed germination and vigour, and on greenhouse emergence in thepresence of Fusarium graminearum Schw. Maize seeds were treated with four pesticides: Apron® XL (metalaxyl),Thiram (thiram), Celest® XL (fludioxonil, metalaxyl) and Apron® Star 42 WS (thiamethoxam, metalaxyl,difenoconazole). Viability and vigour of the treated seeds were determined. Thereafter, seeds were planted undergreenhouse conditions. The control consisted of water-treated seeds. None of the pesticides reduced the standardgermination under laboratory conditions and none had any effect on the quantity of leachate (measured asconductivity) or moisture content of the seeds. The different treatments also had no effect on germination or onseedling weight increase among treatments after rapid imbibition and there was no difference in germinationamong treatments following the cold test. The proportion of diseased plants harvested from F. graminearuminoculated soil was significantly reduced by Apron® Star 42 WS and Celest® XL. The vigour tests indicated thatnone of the pesticides tested affected the seeds negatively and that plant biomass in the presence of the pathogen,F. graminearum, was increased after the application of the pesticides to the seeds, with the exception of seedstreated with Apron® XL.