Southeast Kansas 2020 wheat variety test results
The Kansas State University Crop Performance Tests were conducted in replicated research fields throughout the state. Crop production is dependent on many factors including cultivar selection, environmental conditions, soil, and management practices. This report summarizes winter wheat production (hard-red and soft-red varieties) for Parsons, Kansas.
Figure 1. 2020 wheat variety trial at Parson, KS. Photo by K-State Southeast Research and Extension
Overview of wheat variety trials for Parsons, KS
Fifteen hard-red and ten soft wheat varieties were tested in Parsons silt loam soil at the Southeast Research and Extension Center in Parsons. All crop variety trials are managed with conventional tillage. Individual variety results are available at the K-State Crop Performance Test webpage (http://www.agronomy.k-state.edu/services/crop-performance-tests/). This data is part of the 2020 Winter Wheat Performance Tests, SRP 1158 (not available yet).
Wheat was drilled in 7-inch rows at 1.2 million seed/acre (approx. 90 lb/acre) in conventional tillage with an Almaco plot drill on Oct. 23, 2019 in Parsons and harvested June 18, 2020. Plots were 7 feet wide by 27.5 feet long. Fertilizer was applied before planting at a rate of 50-46-30 lb/acre N-P-K (dry), with an additional 60-46-30 lb/acre N-P-K (dry) applied on Feb. 7, 2020 for both hard-red and soft-red cultivars. No fungicide or herbicides were used in wheat.
Rainfall during the 2019-20 wheat growing season was near record highs. Initial rainfall in the fall was very close to average. Beginning in early January, regular high rainfall events increased the cumulative rainfall to well above average. During April, the cumulative rainfall exceeded that received during the previous year. On May 15, 2020, Parsons received 4.7 inches of rain in one 24-hr period. After a very wet spring, however, the rain stopped; Parsons received only 1.18 inches of rain in all of June. This coincided perfectly with wheat harvest. Wet conditions during wheat flowering contribute to fungal disease, in particular Fusarium head blight or scab (De Wolf et al., 2003). There was heavy infestation of scab in some cultivars and wheat fields. The dry conditions at wheat maturity allowed timely harvesting, resulting in little dockage due to scab in 2020.
Temperatures in 2020 were slightly warmer than average, especially during the winter months of December and January. After periods of low temperatures in the late fall, temperatures increased during the winter and remained mild for most of WY20. Below-freezing air temperatures were received on April 17 and 18, and a low temperature of 36.5 on May 9, but were not low enough or long enough to cause damage in the Parsons area.
Winter wheat was planted on 6.9 million acres throughout Kansas. In the variety trials, heading notes were taken on individual varieties. Heading is defined as the date when 50% of the plot had heads emerged. Heading in the hard-red varieties began April 25, 2020, and was complete by April 30. Heading in the soft-red varieties occurred between April 28 and May 1, 2020.
2020 yield results
Yields in all varieties were very good this year (Figures 1A & 2A). The highest yield in the hard-red wheat varieties was measured in WB4401 at 108.8 bu/acre. This is well above the 12-year average yield of 53.1 bu/acre in the variety trials, and the 12-year average yield of 40.7 bu/acre across the state of Kansas.
Yields in soft-red varieties were higher than the hard-red varieties, as has been observed previously (Figure 2A). Soft-red yield of 102.4 bu/acre across all varieties in 2020 was much higher than the 11-year average of 64 bu/ac for soft-red wheats in the variety trials. The yields were similar to those harvested in soft-red wheat in 2012 in the variety trials. The highest yield of 113.9 bu/acre was measured in AgriMaxx 503, but several other varieties had yields over 100 bu/acre.
Cultivars varied in their susceptibility to disease. High rainfall around flowering and heading increases disease pressure (De Wolf et al., 2003). Fungal disease ratings were measured in all varieties as the percent infection and the extent of infection, with 0 being no damage and 10 being highest infection rate. Fusarium head blight (FHB) and stripe rust were both present in the variety trials, and show differences across the soft red wheat varieties (Figure 1B and C). Stripe rust showed greater infection rates than FHB. Varieties with higher yields tended to have better resistance to the fungal diseases.
One advantage of soft-red wheat is their greater resistance to disease. This was observed in the FHB and stripe rust disease ratings (Figure 2B and C). As with the hard-red varieties, those varieties that had greater resistance to diseases tended to have higher yields.
No herbicides or fungicides are normally used in the variety trials to provide an equal comparison based only on genetics. However, timely application of fungicide has been shown to be especially important in high rainfall areas such as southeast Kansas in order to control fungal diseases (De Wolf et al., 2003). Application of appropriate fungicides around flowering are especially important to control FHB (Onofre and De Wolf, 2020).
Figure 1. Summary of hard-red wheat variety trials, Parsons, KS, 2020. A. Yield; B. Fusarium ratings; C. Stripe rust ratings.
Figure 2. Summary of soft-red wheat variety trials, Parsons, KS, 2020. A. Yield; B. Fusarium ratings; C. Stripe rust ratings.
Wheat did exceptionally well this year. The planting conditions in the fall and relatively mild winter led to good plant stands. Notable, many plots were thinner than expected. However, ideal dry conditions during harvest made optimal and timely harvest possible. The high probability of rainfall around May 31 in Parsons often confounds wheat harvest, making fields inaccessible and increasing disease damage.
Different varieties are entered in the variety testing each year. Therefore, it is important to compare variety performance across different growing seasons to get an understanding of how a variety responds under different growing conditions. Information on previous wheat variety performance is available at: www.southeast.kstate.edu/program_areas/crop_production/wheat/Wheat%20Production_2020.pdf
This work is supported by the U.S. Department of Agriculture National Institute of Food and Agriculture, Hatch project 1003478. This data is part of the 2020 Winter Wheat Performance Tests, SRP 1158.
De Wolf, E. D., Madden, L. V., & Lipps, P. E. (2003). Risk assessment models for wheat Fusarium head blight epidemics based on within-season weather data. Phytopathology, 93(4), 428-435.
Onofre, K.A., De Wolf, E.D. 2020. Foliar fungicide efficacy ratings for wheat disease management 2020. KSU Ag Exp Station and Coop Ext Serv. EP130. https://bookstore.ksre.ksu.edu/pubs/EP130.pdf
Gretchen Sassenrath, Cropping Systems Agronomist
Lonnie Mengarelli, Research Assistant, Southeast Research and Extension Center
Jane Lingenfelser, Assistant Agronomist, Crop Performance Testing
Xiaomao Lin, State Climatologist