The U. S. Plant Introduction Collection of cowpea germplasm and a coll
ection of cowpea cultivars were evaluated for bentazon tolerance in th
e field. Most accessions were intermediate in bentazon tolerance; howe
ver, several highly tolerant and highly susceptible accessions were id
entified. Tolerant and susceptible selections from the field experimen
t were evaluated in greenhouse experiments. The most susceptible selec
tions were killed or severely injured by bentazon at 2 kg ae ha-1; the
most tolerant selections were not severely injured by bentazon at 16
kg ha-1.