University of Agricultural Sciences, Dharwad Campus, Karnataka State
Soil carryover study of herbicides viz. atrazine, simazine, prometryne, terbutryn, 2,4-D-Na salt and alachlor herbicides were studied by bioassay crops germination percentages after harvest of main crop. In the first experiment where atrazine and simazine were applied as pre-emergence herbicides and 2,4-D-Na salt as post-emergence herbicides to sorghum crop during rabi season indicated nonsignificant differences among various treatments for groundnut and cowpea as succeeding crops. The germination percentage of blackgram varied significantly among treatments. Atrazine and simazine at 2.0 kg per ha. persisted more and affected:he germination of blackgram more.
In the second experiment, wherein ametryne, prometryne, terbutryn, atrazine and alachlor were applied as pre-emergence herbicides to sorghum, grown with redgram, Bengal gram and saffiower as mixed crops. The results of residual toxicity studies indicated nonsignificant difference amongest treatments for bioassay crops wheat and maize. Cowpea germination was affected greatly by residues of prometryne, amotryne, terbutryn and atrazine herbicides.
In the third experiment, wherein screening of Kharif sorghum genotypes at 0,2,4 and 8.0 kg/ha of atrazine was followed, the residual toxicity was noticed on succeeding crops of wheat, Redgram, Saffiower and gram at 4.0 and 8.0 kg/ha.
