Assessment of the risk of environmental pollution after using jonsongrass herbicides and physiologically active substances
2008
Serafimov, P., Institute of Forage Crops, Pavlikeni (Bulgaria) | Mladenova, R., Plant Protection Institute, Kostinbrod (Bulgaria) | Manova, R., Plant Protection Institute, Kostinbrod (Bulgaria) | Shchereva, D., Plant Protection Institute, Kostinbrod (Bulgaria) | Nakova, R., Plant Protection Institute, Kostinbrod (Bulgaria)
Risk assessment was made of pollution of soil and plant production with residues of Johnsongrass herbicides used for controlling grass weeds (including Johnson grass in stubble and in a soybean stand) and physiologically active substances produced from different parts of Johnson grass exerting an inhibitory influence on seed germination and development. Residue amounts of pesticide and their hydrolysis products were determined in soybean seeds, soybean pods and soil after application of plant protection products based on fluazifop-P-butyl and quizalofop-P-tefuryl. Results of chromatographic analyses have shown content of the parent pesticide fluazifop-P-butyl in all tested products at levels below limit of detection of the used method. Low content of the hydrolysis product fluazifop free acid was found mostly in soybean seeds (0.06 mg/kg) and even lower level in soil (0.04 mg/kg). Analysis of plant material and soil sample for quizalofop-P-tefuryl 30 days after treatment has shown presence of neither ester nor free acid residues of the pesticide in measurable concentrations. Extracts prepared from Johnson grass rhizomes had a significant inhibitory effect on length of primary germ of soybean; water extracts from Johnson grass leaves + stems also produced an inhibitory influence on soybean germination and initial development. Strong correlation was found between extract concentration and inhibition degree for soybean germination and development of primary germ. The inhibitory effect of plant extracts from Sorghum halepense (L.) Pers was also due to content of cyanoglycosides and condensed tannins.
显示更多 [+] 显示较少 [-]