Francis, a very high-yielding, long grain rice variety developed and released by the University of Arkansas Agricultural Experiment Station this year, should be a big hit with Arkansas producers.
In trials conducted in Arkansas and other Southern rice states, Francis has consistently been the highest-yielding conventional variety, often exceeding the closest competitor by five to 10 bushels per acre.
Date of planting studies show that Francis reaches 50 percent heading in about the same time as Wells. Straw strength is similar to that of Wells and LaGrue, but Francis is approximately 2 inches shorter than Wells and 5 inches shorter than LaGrue.
Francis was named in honor of Francis J. Williams (1923-2001), director of the Arkansas Rice Research and Extension Center at Stuttgart from 1953 to 1988.
Although many producers are excited about the yield potential of this new variety, they should note that Francis is susceptible to several important diseases and thus should not be planted in high-risk fields. Because it is susceptible to rice blast disease, it should be planted in fields that have adequate water to maintain a good flood, particularly during the reproductive growth stages. Besides blast, Francis is rated very susceptible to kernel smut and false smut, moderately susceptible to straighthead, and moderately susceptible to sheath blight.
A preventative application of propiconizole fungicide (Tilt or Propimax) should be applied during the boot stage in fields that have a history of kernel smut. Fungicides (Quadris or Gem) may also be needed to prevent blast in certain areas and years.
Planting date studies conducted at the Rice Research and Extension Center from 2000 to 2002 show that Francis has very stable yields throughout the planting season, but as with most other currently grown varieties, yields tend to be better when the variety is planted earlier. Compared to other varieties, Francis has performed well when planted in early to mid June.
Based on seed weight, 87.2 pounds per acre (1.9 bushels per acre) is required to obtain the recommended 40 seed per square foot or 23 seed per row foot on a 7-inch row spacing.
Although seedling vigor tests have not been performed, visual observations in variety studies suggest that Francis has good seedling vigor and is comparable to LaGrue. Seeding rate studies show that Francis has excellent tillering ability to compensate for thin stands.
The recommended nitrogen rate for Francis grown on silt and sandy loam soils following soybean in rotation is 150 pounds of nitrogen per acre. This recommendation is for nitrogen applied in a two-way split application — 105 pounds of nitrogen per acre is applied preflood and followed by 45 pounds of nitrogen per acre at midseason.
The total and preflood nitrogen rates should be increased by 30 pounds of nitrogen per acre for rice grown on clay soils.
Optimum efficiency of preflood nitrogen is critical to obtaining the best yields from this variety. The preflood nitrogen should be applied to dry soils and fields should be flooded as quickly as possible after application.
Approximately 2,500 acres of Francis were grown for seed production during 2002. Based on a survey of seed growers, field performance has been extremely good. Excellent yields were made in these seed fields that were planted with very low seeding rates. The yields have ranged from 156 to 203 bushels per acre at an average seeding rate of 33 pounds per acre. The average nitrogen rate applied to these fields was 195 pounds of nitrogen (430 pounds of urea) per acre.
While much of the extra nitrogen is needed to compensate for the thin stands in these fields, Francis yields in on-farm variety trials conducted by Rick Cartwright have been the best when higher nitrogen rates were applied. However, growers should keep in mind that excessively high nitrogen rates lead to increased lodging, increased kernel smut, and increased sheath blight.
Some seed producers expressed concern about a very low level of off-type plants present in Francis. However, this diversity is normal for newly-released varieties and probably adds to the high-yield potential. Much of this diversity will be reduced as seed producers rogue seed fields in the future.
The University of Arkansas is committed to releasing improved varieties in as short of time as feasible. Due to improvements in our breeding program, such as the winter nursery conducted in Puerto Rico, the time required for release of new varieties has been reduced from 12 to 15 years to as little as seven or eight years.
Evidence of the value of the rice breeding program to Arkansas producers can be seen by observing the state average rice yields over the past 15 years. Average rice yields have increased by almost 2 bushels per acre per year from 115 bushels per acre in 1985 to 139 bushels per acre in 2001.
Charles E. Wilson Jr. is the Extension rice agronomist at the University of Arkansas Rice Research and Extension Center in Stuttgart. e-mail [email protected].