Managing Crop Diseases with Fungicides

This guide contains a list of fungicides labeled for use in South Dakota at the time of publication. The list is dynamic and prone to frequent changes. It therefore should not be considered as a substitute for label information. Always read and follow label directions for approved uses of these products, and check with the South Dakota Department of Agriculture for up-to-date product registration information

Near-infrared Reflectance Spectroscopy Analysis of Hard Red Spring Wheat Quality

Plant breeding programs evaluate large numbers of breeding lines for quality characteristics. Traditional methods of determining quality have two major disadvantages. First, most traditional methods require the destructive testing of seeds, therefore limiting the testing to later generations in a breeding program. Secondly, traditional methods require a great deal of time. This experiment was designed to use Near-Infrared Reflectance Spectroscopy (NIRS) for rapid, non-destructive analysis of whole wheat seed. Comparisons were made between the results of NIRS and traditional quality analysis characteristics such as test weight, protein, hardness, ash, mix absorption and loaf volume. Material analyzed included advanced lines from the Uniform Regional Hard Red Spring Wheat Nursery (URN) and from the South Dakota State University Spring Wheat Breeding Program (SD). The URN was classified as a wide and diverse genetic and environmental base while SD was classified as a relatively narrow genetic and environmental base. The URN was used as a validation set to predict its own material and also the SD material. The SD material was also used as a validation set to predict its own material and the URN material. After analysis by NIRS, all sample data were used to determine a set of calibration equations. These equations were then used to identify a validation set of data points for comparison. The data from this validation set was paired with corresponding traditional quality data and analyzed using the least squares regression method. Final data has shown that wheat protein can be predicted accurately by the NIRS system. Other quality factors that showed promise for accurate predictions and could be useful in a breeding program are test weight, flour protein and possibly wheat ash. In this study, we found that using a very narrow environment/genetic base to predict a very narrow environment/genetic base had the better R2 values and proved to be the best prediction set. We also found out that a wide environment/genetic base predicting a narrow or a wide environment/genetic base produced relatively lower values when predicting the quality factors

Effects of Pre- And Postanthesis Applications of Demethylation Inhibitor Fungicides on Fusarium Head Blight and Deoxynivalenol in Spring and Winter Wheat

Anthesis is generally recommended as the optimum growth stage for ap- and PA resulted in the highest ̄C values for IND, 52.2 and 51.5%, respecplying a foliar fungicide to manage Fusarium head blight (FHB) and the tively, compared with 45.9% for CL, 41.3% for PL, and less than 33% for Fusarium-associated toxin deoxynivalenol (DON) in wheat. However, CE and PE. Anthesis and postanthesis treatments reduced mean IND by because it is not always possible to treat fields at anthesis, studies were 14.9 to 29.7% relative to preanthesis treatments. The estimated effect size conducted to evaluate pre- and postanthesis treatment options for managwas also statistically significant for comparisons between CA and CL and ing FHB and DON in spring and winter wheat. Network meta-analytical PA and PL; CA reduced IND by 11.7% relative to CL, whereas PA remodels were fitted to data from 19 years of fungicide trials, and log reduced the disease by 17.4% relative to PL. Differences in efficacy against sponse ratio (L) and approximate percent control (C̅) relative to a nontreated IND between pairs of prothioconazole + tebuconazole and metconazole check were estimated as measures of the effects of six treatments on FHB treatments applied at the same timing (CE versus PE, CA versus PA, and index (IND: mean percentage of diseased spikelets per spike) and DON. CL versus PL) were not statistically significant. However, CA and CL The evaluated treatments consisted of either Caramba (metconazole) apoutperformed PA and PL by 7 and 12.8%, respectively, in terms of effiplied early (at heading [CE]), at anthesis (CA), or late (5 to 7 days after cacy against DON. All application programs had comparable efficacy anthesis; CL), or Prosaro (prothioconazole + tebuconazole) applied at the against IND between spring and winter wheat types, but efficacy against same three times and referred to as PE, PA, and PL, respectively. All DON was 10 to 16% greater for spring than winter wheat for applications treatments reduced mean IND and DON relative to the nontreated check, made at or after anthesis. All programs led to an increase in mean grain but the magnitude of the effect varied with timing and wheat type. CA yield and test weight relative to the nontreated check