MON 37500 Soil Residues Affect Rotational Crops in the High Plains¹

Abstract

MON 37500 is a sulfonylurea herbicide that selectively controls Bromus spp. in winter wheat. Field studies were conducted near Sidney, NE, and Archer, WY, to determine the sensitivity of corn, foxtail millet, grain sorghum, proso millet, and sunflower to soil residues of MON 37500. MON 37500 was applied to winter wheat at 0, 35, 69, and 139 g/ha in the autumn of 1997. Rotational crops were no-till seeded into the standing residues of the previous year's crop from 1999 through 2001. Grain yields for corn, foxtail millet, and proso millet planted 18 to 20 mo after herbicide application were not affected by soil residues of MON 37500. In contrast, average grain yields of grain sorghum were reduced from 1,760 to 30 kg/ha at Archer and from 4,480 to 390 kg/ha at Sidney as MON 37500 rates increased from 0 to 139 g/ha. Thirty to 32 mo after herbicide application, average grain yields of grain sorghum were reduced from 2,360 to 620 kg/ha at Sidney and average aboveground biomass was reduced from 4,000 to 1,800 kg/ha at Archer as MON 37500 rates increased from 0 to 139 g/ha. Nineteen to 20 mo after herbicide application, average sunflower seed yields were reduced from 1,450 to 20 kg/ha at Archer and from 1,830 to 540 kg/ha at Sidney as MON 37500 rates increased from 0 to 139 g/ha. Visual injury was observed 31 to 32 mo after herbicide application, but drought in 2000 prevented collection of seed yield data. In the High Plains, foxtail millet, proso millet, and corn may be successfully grown 18 to 20 mo after the application of MON 37500 to winter wheat. Successful production of grain sorghum and sunflower may require a minimum recrop interval between treatment and planting of >36 mo.

Control of weed barley species in winter wheat with sulfosulfuron at different rates and times of application

“…Ball and Walenta (1997) observed a small height reduction in winter wheat with sulfosulfuron applied POST at 35 g ha −1 , but the yield was not reduced. Lyon et al . (2003) noted that winter wheat treated with sulfosulfuron at 139 g ha −1 yielded less than the untreated wheat.…”

Pyroxsulam Compared with Competitive Standards for Efficacy in Winter Wheat

“…In the same study, propoxycarbazone was slightly more effective than sulfosulfuron on downy brome when each was applied early SP or late SP. Propoxycarbazone has also been shown to have a shorter recropping interval than sulfosulfuron for crops commonly rotated with wheat in the central Great Plains (Geier and Stahlman 2001;Lyon et al 2003;Peeper et al 2009). …”

Response of wild barley (Hordeum spontaneum) and winter wheat (Triticum aestivum) to sulfosulfuron: The role of degradation

“…2003). However, crop injury and rotational restrictions must be considered (Kelley & Peeper 2003; Lyon et al . 2003) when applying sulfosulfuron PRE.…”

“…Sulfosulfuron can be applied pre-emergence (PRE) and some experiments have shown a higher efficacy level of PRE, compared to postemergence (POST), application in wheat (Blackshaw & Hamman 1998) and tomato (Eizenberg et al 2003). However, crop injury and rotational restrictions must be considered (Kelley & Peeper 2003;Lyon et al 2003) when applying sulfosulfuron PRE.…”