Tolerance of Processing Tomato (Solanum lycopersicum L.) Varieties to Thifensulfuron-Methyl

Abstract

Field experiments were conducted at the Ohio Agricultural Research and Development Center in Wooster, OH, in 2005, 2006, and 2007 to evaluate the tolerance of eight tomato varieties to thifensulfuron-methyl and POST control of broadleaf weeds. Herbicide treatments included thifensulfuron-methyl at 0, 6, and 12 g ai ha−1. In 2005, significant injury was observed in variety TR122244 at 1 and 3 wk after treatment (WAT). The highest crop injury in 2005 was 38% at 1 WAT for variety TR122244. However, this variety experienced a conflicting effect on crop marketable yield when treated with the low and high rates of thifensulfuron-methyl in 2005. Variety TR122244 had the highest crop injury, yet produced the highest marketable yield when treated with either rate of thifensulfuron-methyl. At 3 WAT in 2005, significant injury occurred in variety 11111120, with 13% injury recorded for both the high and low rates of thifensulfuron-methyl. No significant injury resulted from either rate of thifensulfuron-methyl at 1, 3, or 6 WAT in 2006 or 2007. However, in 2006 a significant marketable yield reduction was observed for variety 97045116 when treated with the high rate of thifensulfuron-methyl. No varieties experienced significant marketable yield effects or injury when treated with either rate of thifensulfuron-methyl in 2007. Registration of thifensulfuron-methyl herbicide is not recommended at this time because of the potential for crop stunting and yield reduction in certain tomato varieties.