Arkansas rice experts collect and share reliable data
Editor’s note: To view the Rice Information Sheet No. 170 in its entirety, including all of the tables, go to www.uaex.edu and search for Arkansas Rice Performance Trials, 2009-2011 or contact your local University of Arkansas Cooperative Extension office.
Choosing a variety is generally based upon past experience, seed availability, agronomic traits and variety yield potential. When choosing a rice variety, grain and milling yields, lodging, maturity, disease susceptibility, seeding date, field characteristics, the potential for quality reductions due to pecky rice and market strategy should all be considered.
Variety performance data included in the Rice Information Sheet No. 170 are from the Arkansas Rice Performance Trials (ARPT), disease observation plots in grower fields and from seeding date studies conducted during 2009-2011. Additional information can be found on the Arkansas Cooperative Extension Web site (www.uaex.edu) and the annual B.R. Wells Rice Research Series publication (http://www.uark.edu/depts/agripub/Publications/researchseries/).
Arkansas Rice Performance Trials
Varieties grown in the ARPT in 2011 averaged 162 bu/A of rough rice compared to the state average yield of 152 bu/A as reported by the USDA Crop Reporting Service. Data averaged over years and locations are more reliable than a single year of data for evaluating rice performance for such important factors as grain and milling yields, kernel size, maturity, lodging resistance, plant height and disease susceptibility. It becomes more critical to evaluate as many years of information as possible, particularly when extreme heat is experienced such as it was during 2010 and 2011.
The ARPT and disease observation tests are supported through grower check-off funds administered by the Arkansas Rice Research and Promotion Board. These studies are conducted every year to compare promising new experimental lines and newly-released varieties from the breeding programs in Arkansas, Louisiana, Texas and Mississippi with established varieties currently grown in Arkansas.
Location, Location, Location
The 2010 ARPT were conducted at six locations in Arkansas. Multiple locations each year allow for continued reassessment of the performance and adaptability of advanced breeding lines and commercial varieties to environmental conditions, soil properties, and management factors. Twenty-five entries, which were either promising breeding lines or established varieties, were grown in each of the four maturity groups (early, very short, short and mid-season) for a total of 100 entries.
The 2011 ARPT tests were located at Pine Tree (PTBS), Newport (NBES), and the Jerry and Blake Goodman farm in Clay County. The studies were seeded on April 12, May 26 and April 2, respectively. Cultural practices varied somewhat among the ARPT locations, but, overall, the trials were grown under conditions for high yield. Nitrogen was applied to ARPT tests located on Experiment Stations in a single application of 120 lbs N/A at preflood on the silt loam soils and 150 lbs N/A on the clay soils. Phosphorus and potassium fertilizers were applied before seeding at each location.
Averaged across all of the locations, RiceTec XP753, Jupiter and Roy J were the top-yielding varieties in the 2011 ARPT. RiceTec XP753, Roy J and Francis were the highest-yielding long-grains in 2011. RiceTec XL723, CL XL729 and CL XL745 have been the highest-yielding cultivars averaged across the past three years. Roy J, Francis and Jupiter were the top three yielding conventional varieties from 2009 to 2011.
Ratings for disease susceptibility should be evaluated critically to optimize variety selection. Varieties should be selected for specific fields, relative to the potential yield limitations observed in historical yields. For example, Francis and Wells are both susceptible to rice blast disease and should be planted in fields with low risk of this disease. Other varieties should be considered for fields that have limited water availability, poor water-holding ability, historical blast infestations, high risk of straighthead and tree lines or other natural barriers that encourage long dew periods.
Considerations for bacterial panicle blight should also be considered. High-risk fields should be planted to resistant varieties (hybrids and Jupiter). Conventional rice should be planted early and prior to planting hybrids. Conventional rice should be managed as timely as possible to avoid unnecessary stress.
Ratings are a general guide based on our expectations of the cultivar reaction under conditions that strongly favor disease; however, environment will modify the actual reaction in different fields. Also, resistance to particular diseases, like blast, can be overcome by the fungus over time. Do not expect these ratings to be an absolute predictor of performance with respect to a particular disease in all situations.
Each year replicated variety trials are established in numerous grower fields to monitor rice variety reaction to diseases. Yield information from these trials provides additional valuable information on how varieties and advanced experimental lines perform across the state when subjected to different environments and management practices, as shown in the table on page 12.
Variety disease reaction data from these trials are used to help establish disease susceptibility ratings. A Clearfield-only version is also conducted at a few locations to enable monitoring the impact of Newpath herbicides on the Clearfield varieties. Averaged across all locations, Roy J and Taggart were the highest-yielding cultivars tested in the Arkansas Disease Monitoring Tests. Yield variability among the various locations not only represents different environments but also susceptibility to various diseases present at specific locations.
New varieties included in the 2011 Arkansas Rice Performance Trials include Caffey, CL152, CL162, Jazzman 2, RiceTec XP753, XP754 and CL XP756. Additional information on specific varieties not listed in the Rice Information Sheet No. 170 is available upon request. Please contact your local county Extension agent.
This information is provided by: Charles E. Wilson, Jr., Professor/ Director RREC/Extension Agronomist-Rice; Karen Moldenhauer, Professor, RREC; James Gibbons, Research Assistant Professor; Rick Cartwright, Professor/Extension Plant Pathologist; Fleet Lee, Professor; Rick Norman, Professor; John Bernhardt, Research Assistant Professor; Charles Parsons, Program Associate; Donna Frizzell, Program Associate; Jamie Branson, Program Technician; Maurice Blocker, Program Associate; Jill Bulloch, Program Technician; Edward Castaneda, Program Technician; Stewart Runsick, Program Associate; and Ralph Mazzanti, Program Associate.