Addition of a monovalent cationic pesticide to improve efficacy of bipyridyl herbicides in Hulah Valley soils.
Bipyridyl herbicides are widely used in agriculture and gardening for non-selective weed control. Since they are toxic and relatively expensive, it is ecologically and economically desirable to reduce the amounts applied. A decrease in efficacy of these herbicides is caused by dust accumulated on leaves of weeds. This inactivation arises from the adsorption of the herbicides on dust particles, mainly made of clay minerals, lime and soil organic matter. In order to improve the efficacy and so lower the amounts applied, formulations were developed which include cationic pesticides approved for agricultural use, such as mepiquat or difenzoquat. Such addition restored the efficacy of the bipyridyl herbicides by reducing their binding to dust particles. The proposed formulations, which were tested on a number of different dust-covered plants, allowed the amounts of herbicide applied to be reduced to 50% of the minimum recommended rate. Neither mepiquat or difenzoquat had any herbicidal activity when sprayed alone at the added rates. The results suggest a procedure that may lower the required rates of contact herbicides, reducing costs and toxicity. This procedure, which can be applied immediately, may have broad implications in farming and gardening.
Rytwo
Giora
G
Tel Hai Academic College, Biotechnology and Environmental Sciences Department, Upper Galilee 12210, Israel. rytwo@telhai.ac.il
Tavasi
Mordechai
M
D000327:Adsorption; D001937:Brassica; D002414:Cations, Monovalent / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004391:Dust; D006540:Herbicides / Q000191:economics / Q000378:metabolism* / Q000633:toxicity; D018551:Solanum lycopersicum; D012987:Soil; D016896:Treatment Outcome
D002414:Cations, Monovalent; D004391:Dust; D006540:Herbicides; D012987:Soil