Effects of Herbicides on Nitrogen Fixation of Alfalfa (Medicago sativa) and Red Clover (Trifolium pratense)

Abstract

EPTC (S-ethyl dipropylthiocarbamate), benefin (N-butyl-N-ethyl-α α,α-trifluoro-2,6-dinitro-N-propyl-p-toluidine], butralin[4-(1,1-dimethylethyl)-N-(1-methylpropyl)2,6-dinitrobenzenamine], diclofopmethyl {methyl 2-[4-(2,4-dichlorophenoxy)phenoxy]-propanoate} and 2,4-DB [4-(2,4-dichlorophenoxy)butyric acid] were evaluated in the greenhouse for effects on growth, nodulation, and NH3 production of alfalfa (Medicago sativa L.) and medium red clover (Trifolium pratense L.). Some reduction in nodulation occurred from some rates of the herbicides, but reduction in nodulation was usually associated with reduced plant growth caused by herbicidal injury.