Chairman's Report, 2013


Rice Research Board Chairman

Brett Scheidel

Welcome to the 45th annual report to the California Rice Growers.  In the following pages we report on grower-funded research from 2013 that is crucial to the California rice industry. We track progress on many fronts, such as rice variety breeding, weed and disease management, fertilizer guidelines, invertebrate pest control, and water use efficiency. We also learn about the use of infrared technology in rice drying, and developing rice straw into value-added products such as rice board made with biodegradable plastic and rice straw-based nanomaterials with potential for commercial application. One new study profiled an aroma volatile in rice. Two other new projects focused on the environment, sizing up the prevalence of mercury and arsenic in rice-growing areas. Indeed, it was a busy year for research in fields, laboratories, and greenhouses.

California’s public rice-breeding program is conducted and managed by scientists at the Rice Experiment Station (RES). The program has made 43,824 crosses and released 44 improved public rice varieties since its inception in 1969. A new aromatic long-grain line has been approved for release as A-202. Steady progress is reported in all five major project areas in the Rice Breeding Program section.

Testing of promising experimental lines took place at 17 farm locations and at RES in 2013. Top-yielding advanced lines are reported for each of the three maturity classes, along with yields of standard varieties. Research continues at Twitchell Island in the Sacramento–San Joaquin Delta to evaluate the potential for growing cold-tolerant rice varieties in this challenging environment. This work and results of statewide testing are described in the Rice Variety Trials section.

Molecular markers are an important tool for identifying desirable traits in rice. Work continues with next-generation sequencing techniques that greatly accelerate genetic studies for variety development. Progress on mapping populations of rice continues through generation advance and the development of mutant populations. This work is reported in Molecular Marker-Assisted Rice Improvement.

Fertilizer research in 2013 focused on three areas—potassium status, nitrate leaching, and management practices for growing rice under alternating flooded/dry conditions. The potassium study suggests that fertility may need to be addressed at soil potassium levels below 120 ppm. Research on nitrate leaching dug deep into the soil and measured nitrate in water below the rice root zone. Results indicate that nitrate leaching is not a concern for the majority of California rice soils. The third area of research evaluated water management practices to assess their influence on nitrogen response and greenhouse gas emissions. These studies are reported in Improving Fertilizer Guidelines for California’s Changing Rice Climate.

Weed control research examines new and existing herbicides, as well as combinations and sequential applications. Research on continuous flood, pinpoint flood, and drill-seeded rice is seeking the best herbicide and management combinations for each of these systems. Research on propanil resistance in smallflower umbrellasedge and ricefield bulrush continued. Updates are provided on two invasive weeds—winged primrose willow and Indian marshweed—in Weed Control in Rice.

Rice disease research focused on evaluating fungicide products on stem rot, aggregate sheath spot, and rice blast. Fungicide trials ran in M-206 fields to evaluate Quadris® and the more recently released Quilt Xcel™. Treated plots increased yields over control plots by 200 to 360 pounds/acre. This work is reported in Rice Disease Research and Management.

The spring 2013 flight of rice water weevil (RWW) was low to moderate but unusually long. Research into control of this pest focuses on insecticidal controls. Seven different active ingredients were studied in ring plots at RES. Work also continued on the susceptibility of different rice varieties to RWW, control of tadpole shrimp, the impact of rice pesticides on nontarget insects, and on a possible connection between red-shouldered stinkbug and “pecky” rice. Read about this work in Protection of Rice from Invertebrate Pests.

Research on how pesticides important to rice culture degrade in the environment continued on the neonicotinoid insecticide clothianidin, the herbicide imazosulfuron, and the herbicide benzobicyclon. Laboratory studies indicate that clothianidin remains primarily in water but will move into soils with high concentrations of organic matter, photodegradation of imazosulfuron is probably an important process in its dissipation from rice fields, and confirm that benzobicyclon’s ability to volatilize from field water is minimal. Read about this research in Environmental Fate of Rice Pesticides.

A new project examined data from government sampling programs to assess the extent of mercury in California rice systems. Levels tend to elevate in winter. However, stream flow data are insufficient and thus more study is needed to determine the role rice systems may play in winter. Read about this work in Mercury in California Rice Systems.

To improve our understanding of arsenic in the Sacramento Valley, the rice industry contracted with consulting firm CH2M Hill to summarize existing water quality information and current knowledge of arsenic occurrence in rice-growing areas. The information gathered thus far indicates that arsenic is naturally occurring and that rice farming is not adding to background arsenic content. Avenues for further research are suggested in Arsenic in Rice Growing Areas of the Sacramento Valley.

Another project is seeking opportunities to conserve water in California rice systems. Research is focused on the development of a crop-development model that can predict days to panicle initiation, heading, and maturity based on planting date. The model accurately predicted days to heading for S-102 and L-206. Work in 2014 will focus on completing a photothermal model to predict panicle initiation and maturity. Read more in Identifying Opportunities for Improving Water Use Efficiency in California Rice Systems.

A new study is developing analytical methods for profiling rice aroma volatiles such as one compound associated with a “popcorn-like” aroma in certain rice varieties.  This type of information could prove useful in rice-breeding efforts. This research is reported in Analytical Methods for Profiling Rice Aroma Volatiles.

Research continues with infrared heating technology, focusing last year on improving rice-drying efficiency, milling quality of rough rice, and stability of rice bran. Results show this technology could be a feasible alternative to conventional heating. However, further study is needed on its effects on brown rice under storage and to evaluate cooking and sensory quality.  It could also lead to new processing methods for edible oil from rice bran. This research is reported in New Techniques for Improved Shelf Life of Rough and Brown Rice and Stabilization of Rice Bran.

Another project continues its successful research developing the technology to transform rice straw components such as cellulose, silica, and lignin into the raw material for value-added industrial products. This work is reported in Novel Nanomaterials and Performance Industrial Products.

A UC researcher worked with two ranches to demonstrate how to “put up” treated rice-straw forage under high moisture. He is assessing any changes in forage value using this method of baling rice straw for cattle feed. Read about this work in Demonstration of Rice ‘Strawlage’ Production.

Research also continued on using rice straw as a feed supplement in dairy rations. Work in 2013 focused exclusively on improving the digestibility of rice straw. One study looked at whether treating rice straw with an enzyme product would enhance digestibility. Read about this in Dairy Feeding of Rice Hay.

Finally, research continues at California State University, Chico, to develop a composite board made from rice straw and a biodegradable plastic. Tests show that tensile and impact properties are comparable to plywood. Read about this work in Rice Board Development with Biodegradable Plastics.

 That’s a quick summary of what you’ll find in this year’s annual report. Read on and learn how our ongoing investment in research continues to reap dividends for the California rice industry. The future holds both promise and challenge. I believe we will be well-positioned for both because of our willingness to rely on the scientific community to find the answers we need. Wishing you all the best in 2014 for a productive, prosperous, and safe season.