Movement and degradation of indaziflam in a Pecan Orchrad

Abstract:

Indaziflam is a new preemergence herbicide to control annual grass and broadleaf weeds in orchards. Currently there is limited information on its dissipation under field conditions. This study was conducted in a pecan orchard where some trees showed sporadic injury symptoms about four months after applying indaziflam. The objectives of this study were to evaluate the movement of indaziflam due to flood irrigation and determine the rates of degradation of indaziflam. Soil samples were collected at 0-15, 15-30 and 30-46 cm depth 26, 63, 90 and 126 days after treating impacted and unimpacted areas with 0, 36.5 and 73.1 g a.i. ha^-1. Indaziflam was detected in soil samples collected at each depth from areas treated with 0, 36.5 and 73.1 g a.i. ha^-1 suggesting that indaziflam moved both horizontally and vertically. Average half-life of indaziflam was obtained as 40±11 days and indaziflam concentrations consistently decreased with increasing soil depth and time. Indaziflam concentrations were greater in the unimpacted area than in the impacted area and mass recoveries were greater in plots treated with 36.5 g a.i. ha^-1 compared with those treated with 73.1 g a.i. ha^-1. This is the first field study to evaluate the indaziflam dissipation in future, phytotoxic effects of indaziflam should be studied under field conditions.