Evaluation of herbicide options for control of invasive annual ground cherry (Physalis divaricata D.Don.) in corn

Annual ground cherry (Physalis divaricata) is an invasive weed in farmlands located in western Iran, but there is little information on effective options for its management, particularly in corn. Greenhouse and field studies were conducted to evaluate the performance of herbicide options consisting of mesotrione + s-metolacholor + terbuthylazine, bromoxynil + MCPA, foramsulfuron + iodosulfuron, 2,4-D + MCPA, rimsulfuron and nicosulfuron + rimsulfuron alone and in combination with ammonium sulphate (AMS) and citogate for Ph. divaricata control in corn. In the greenhouse study, only Mesotrione + s-metolacholor + terbuthylazine and bromoxynil + MCPA mixture provided satisfactory control of Ph. divaricata among the evaluated herbicides. In field study, each of mesotrione + s-metolacholor + terbuthylazine or bromoxynil + MCPA efficiently suppressed Ph. divaricata. Nevertheless, bromoxynil + MCPA had higher efficacy so that applying 75% of its recommended dose resulted in more than 80 % control of Ph. divaricata. Considering both greenhouse and field studies, mesotrione + s-metolacholor + terbuthylazine as well as bromoxynil + MCPA were found to be suitable options for Ph. divaricata in corn. Results also suggest the need of adding of AMS to improving weed control by these herbicides, particularly in bromoxynil + MCPA.