Purple Nutsedge Control and Potato (Solanum tuberosum) Tolerance to Sulfentrazone and Halosulfuron¹

Abstract

Five field studies on sandy soils with ≤ 1% organic matter in south Texas showed that halosulfuron at 0.066 kg/ha preemergence (PRE) controlled ≥ 92% purple nutsedge and at 0.066 kg/ha postemergence (POST) controlled purple nutsedge 77 to 95%. Sulfentrazone at 0.11 to 0.28 kg/ha PRE or POST controlled purple nutsedge < 65% at one location but > 75% at two other locations. Poor control at the one location may have been due to a lack of early-season rainfall or irrigation. Potatoes were stunted 5 to 26% with halosulfuron PRE, whereas POST treatments caused 7 to 40% stunting. Sulfentrazone at 0.11 to 0.28 kg/ha applied PRE or POST caused 2 to 38% stunting. ‘Atlantic’ potato stunting with sulfentrazone POST at 0.14 to 0.28 kg/ha was ≥ 20%, whereas ‘Snowden’ and ‘1625’ potatoes were stunted ≤ 20%. Potato yields were reduced 65 and 39% with sulfentrazone and halosulfuron POST, respectively, at the high rates, but yield reductions occurred with all POST treatments on Atlantic potatoes 10- to 20-cm tall. Halosulfuron PRE at 0.033 kg/ha and sulfentrazone PRE at 0.14 kg/ha did not reduce yields; however, all other treatments of halosulfuron and sulfentrazone reduced potato yields.

Evaluation of Sulfonylurea Herbicides on Cool and Warm Season Turf Species

“…Sulfonylurea herbicides can be used for grassy weed control as soil and foliar applications (10). This class of herbicides has been studied extensively for use in agricultural crops (4,5), and has been utilized for sedge control in turf (1,8). However, many of the new chemicals have not been fully tested for safety or control of turf species.…”

“…Sulfonylurea chemistries are an economically important class of herbicides used for weed control in agricultural crops as well as turf (2,5). The characteristics are very low use rates, excellent selectivity, and low mammalian toxicity (3).…”

Residual Herbicide Dissipation in Vegetable Production

“…Halosulfuron (Grichar et al, 2003;Nelson & Renner, 2002;Vencill et al, 1995), sulfentrazone (Grichar et al, 2003;Wehtje et al, 1997), and metolachlor (Cornelius et al, 1985;Obrigawitch et al, 1980) provide soil residual activity on Cyperus species with control often extending for many weeks or months after applications. While these herbicides are viable alternatives to fumigation in vegetable production, they may cause injury to newly transplanted crops (Figure 2), and potential carryover issues to subsequent crops.…”

Pest control with drip‐applied dimethyl disulfide and chloropicrin in plastic‐mulched tomato (Solanum lycopersicum L.)

“…The currently registered herbicides do not provide effective Cyperus spp. Control, except for halosulfuron . Tumbleson and Kommedahl reported that one Cyperus esculentus tuber produced 6900 tubers and 1900 shoots within 1 year.…”