Purple nutsedge (Cyperus rotundus) tuber production and viability are reduced by imazapic

Abstract Purple nutsedge can persist between growing seasons as tubers in the soil. Imazapic is often used for control of purple nutsedge in peanut. The objectives were to evaluate the effect of various rates of imazapic on tuber production. Pre-sprouted tubers were transplanted into outdoor microplots and treated after six wk of growth with six rates of imazapic POST and a nontreated control. All shoots emerged at the time of application were marked with plastic rings; classification of tubers at exhumation were 1) tubers attached to shoots that were emerged at time of application, 2) tubers attached to shoots that emerged after application, 3) tubers without an aerial shoot during the study. Seven wk after application, the tubers in the microplots were exhumed, classified, quantified, and ability to sprout evaluated. In the nontreated control, there were 544 total tubers, with a log-logistic regression model describing the declining tuber population with imazapic rate. The rate of imazapic that reduced ...