Because of the 16-year summary, the annual report of progress for 1984 has been condensed and is presented at the end of this report. Next year, we will return to the format followed in previous years.

As we approach the 1985 crop year, the principal problems facing the rice industry continue to be unfavorable markets, and the ever-present concerns about air and water quality. The diversion of part of the California rice acreage from short and medium grain to long grain improves marketing options, but improvements in world production still depress prices.

From 1979 through 1983, the Board funded a series of projects to find economic uses for rice straw. The purpose was to reduce or eliminate straw burning. Uses included livestock feed, making fiberboard, paper making, gasification for energy, and even conversion of straw to sugar syrup and protein. All of these uses were technically feasible. None were economically promising. Improvements in burning techniques remain the best solution in the short run. The water quality problem improved somewhat in 1984 through grower cooperation and through use of a few water recirculation systems. Recent research on intentional degradation of pesticides in drainage waters is a promising development.

As chairman of the Board, I particularly want to thank the Board members who have given so generously of their time to make this program successful. Also, I am sure I speak for all rice growers in thanking the many rice research and extension workers for their continued efforts to improve the production and quality of California grown rice.

Lastly, I urge you to vote in the upcoming referendum for continuation of the research and extension programs that have made California rice yields the world's best.

RESEARCH PROGRESS REPORT FOR 1984

Research projects funded for 1984 included the rice breeding work at the Rice Experiment Station at Biggs, seven projects with the University of California, one project with USDA but funded through UC, and one project on rice straw burning with an independent contractor. Associated with the straw burning project was rice board funding to Nowcasting, Inc. and to the Basin Control Council. Only the highlights of the 1984 research projects are presented this year because of the more lengthy 16-year summary report.

VARIETAL DEVELOPMENT, TESTING AND GENETICS

Rice Breeding Program

H.L. Carnahan, S.T. Tseng, C.W. Johnson and J.J. Oster, California Cooperative Rice Research Foundation Inc., Rice Experiment Station, Biggs.

• A new medium grain variety, M-202 is being released to replace M9 in areas where M9 was not already replaced by M-201. Yields from 15 tests averaged 872 pounds per acre higher than M9. Foundation seed (975 cwt) is available for 1985 planting. Compared with M9, M-202 is about 2 days earlier, slightly shorter, more lodging resistant, has slightly smaller kernels and is equal or superior in cold resistance. It is more resistant to stem rot disease and similar in reaction to aggregate sheath spot. M-202 is preferred over M-201 only for later seeding in warmer areas.
• Calmochi 101, a very early short-statured, blanking resistant mochi rice will be increased from breeders seed in 1985 for later release to growers. In eight tests, yields averaged 878 pounds per acre higher than M101. It has pubescent leaves and hulls, is awnless, has larger grains and is preferred in cooking tests by industry.
• Cultural practices are very important for success with the new long grain variety L-202. It is adapted to the warmer two-thirds of the rice growing area. Preferred seeding dates are May 5 to 15, after which water should be maintained shallow through maximum tillering stage. It is resistant to lodging and is highly responsive to nitrogen fertilization. Avoid draining too early, as it dries down quickly but requires the same time from draining to harvesting as medium grains. Fields should be harvested quickly at 19 to 23 percent moisture, as head rice declines rapidly at lower moisture levels. Because it threshes easily, cylinder speeds should be reduced. Any mixtures with short or medium grain will lower market quality.
• Two experimental lines gave exceptional performance in 1984 yield trials. One is a very early medium grain (same maturity as M-101) with greater straw strength, higher milling yield and much greater grain yield. The other is an early pearl (same maturity as S-201) with greater straw strength, better translucency, and higher grain yield than S-201.

Variety Adaptation and Cultural Practices

J.E. Hill, L.A. Post, M.L. Feyler, M. Canavari, D. Snell, D. Munier, S.C. Scardaci, C.M. Wick, B.L. Wier, J.F. Williams, and S.D. Wright. Cooperative Extension, University of California.

• Seventy-six experimental cultivars were tested in 13 variety tests in three maturity groups at 12 locations.
• Several promising experimental cultivars emerged from the very early maturity tests. These included short, medium, long and Calmochi grain types.
• One experimental entry, 81-y-124, has topped the very early test for three consecutive years and also has performed well in the early test. This will be released as M-202, a replacement for M9 in cool areas.
• Tests on phosphorus placement demonstrated that the advantage of surface applied phosphorus is short-lived and that best plant recovery occurs when phosphorus is placed in the soil.
• Research over two years has demonstrated that coated seed will require more careful management than presoaked seed in the establishment of rice stands. Most importantly, timing of herbicide application for grass control is more critical when coated seed is used because of delays in seedling emergence from planting dry seed.

Genetic and Physiological Determinants of Yield and Quality

J. Neil Rutger, J.C. Chandler, T.R. Anderson, E. Peterson, A.O. Bastawisi, S.R. Pinson, Jinguo Hu, and S. Redmon, U.S. Department of Agriculture and the University of California, Davis.

• Development of new sources of germplasm for rice breeders by natural crossing between M-101 and about 400 lines from Japan, Korea, and Taiwan.
• Selection for increased grain size by natural crossing between M-101 and about 200 large grained lines from Africa.
• Identification of adequate field resistance to aggregate sheath spot disease among weedy species of rice that are being used in crosses with cultivated rice.
• Selection of an early mutant from S-201 that matures 7 days earlier, has smaller grains, less white belly, and yielded 25 percent more in a small test plot.
• Further, although slow, progress toward the ultimate goal of hybrid rice for California.
• Successful regeneration of rice plants from cells of immature embryos of L-202 and the regeneration of 274 plants from anthers of rice plants. These techniques may become useful for shortening plant breeding cycles and hastening new variety development.

PEST CONTROL

Weed Control and Improvement of Agronomic Practices

D.E. Bayer, J.E. Hill, S.C. Scardaci, C.M. Wick, J.F. Williams, J. Wrysinski, B. Brandon and E. Roncaroni, Department of Agronomy and Range Science, Cooperative Extension, and the Rice Experiment Station cooperating.

• Twenty-three experimental herbicides were tested at the Rice Experiment Station, Biggs, and at the Rice Research Facility UC Davis. Only a few of these show promise for future study in rice.
• Two experimental herbicides, Londax (Dupont Co.) and Whip (American Huescht Corp.) show good promise for roughseed bulrush and barnyardgrass control, respectively. These herbicides are not registered for rice, but extensive studies are being conducted in support of their registration.
• Confirming previous experiments, treatments of MCPA made at 25 to 35 days after seeding provided the best weed control and least rice injury. Conversely, rice treated at 45 to 55 days after seeding had the poorest weed control and yielded less.
• MCPA additives were evaluated, but they increased injury to rice more than they increased weed control.

Cause and Control of Rice Diseases

R.K. Webster, J. Bolstad, P.S. Gunnell, T. Gordon, C.M. Wick, and S. Scardaci, Department of Plant Pathology and Cooperative Extension, University of California.

• The rice disease frequently referred to in the past as sheath blight is a disease complex of bordered sheath blight caused by the fungus Rhizoctonia oryzae and aggregate sheath spot caused by the fungus Rhizoctonia oryzae-sativae.
• Symptoms of the two diseases are similar, but bordered sheath spot is a. more aggressive disease in California than is aggregate sheath spot.
• Sources of resistance to aggregate sheath spot have been identified, appear to be heritable and, therefore, of value in breeding for resistance.
• Chemical control of stem rot and aggregate sheath spot with Tilt 3.6E appears promising but will require application rates higher than were tested in 1984. Residue data were collected to facilitate registration of the chemical.
• Rice kernel smut was found to be more prevalent than anticipated. Seed treatments that will eliminate inoculum from seed have been identified. There is preliminary evidence that varieties differ in susceptibility.

Protection of Rice From Invertebrate Pests

A.A. Grigarick, J.H. Lynch, M. Oraze and K. Smith, Department of Entomology, University of California, Davis.

• The five most tolerant rice selections to the rice water weevil produced 44 to 55 percent more grain than the variety M9 under very heavy weevil infestations.
• Carbofuran applied seven days after flooding reduced the larvae count of the rice water weevil 49 percent at a 0.5 lb/acre rate and 81 percent at a 1 lb/acre rate.
• Isophenphos applied seven days after flooding reduced the larvae count of the rice water weevil 79 percent at a 1 lb/acre rate and 84 percent at a 2 lb/acre rate. Preflood applications were ineffective.
• Alsystin, a chitin inhibitor, was not effective for rice water weevil control in 1984, although adequate control resulted in previous tests.
• Copper sulfate crystals and two liquid formulations of copper sulfate applied 2.5, 5 and 10 lbs ai per one-half acre-foot of water gave 100 percent mortality of tadpole shrimp by 29 hours in a laboratory test.

PESTICIDE RESIDUES

The Environmental Fate of Pesticides Important to Rice Culture

D.G. Crosby, J.B. Bowers, M.B. Freiberg, R.M. Higashi, Rita Look, R.B. Draper, and D.B. Alger, Department of Environmental Toxicology, University of California, Davis.

• A new, faster, and less expensive analytical method for detection of molinate (Ordram) and thiobencarb (Bolero) in water was developed.
• Molinate residues from all postflood applications had similar dissipation curves with half-lives all close to three days. Preflood soil incorporated molinate had lower water residues. Half-lives were largely independent of holding time over eight days, water depth, or water movement.
• Laboratory experiments showed that solid zinc oxide generates a pesticide-degrading oxident in sunlight. A dilute aqueous solution of zinc oxide sprayed three days after Ordram 10G application in a field experiment caused abrupt loss of residues in the water in only a few hours. Identified breakdown products were harmless and nonpersistent.
• Atmospheric ozone had little effect on rice pesticides in the field.

RICE HARVESTING

Harvesting Equipment

George E. Miller, Bryan M. Jenkins, and Shrini K. Upadhaya, Department of Agricultural Engineering, University of California, Davis.

• A comparison of raspbar and spiketooth cylinders for harvesting M9, M-201 and California Belle rice varieties showed a small advantage in head rice yield for the raspbar but a small increase in cylinder losses.
• The raspbar cylinder harvester capacity declined more drastically than the spiketooth cylinder when evening humidity and dew were encountered.
• Based on current data, there is no clear cut choice between cylinder types for rice harvesting.

RICE QUALITY

Genetic and Environmental Influence on Head Rice

Shu Geng, J.E. Hill, Sakda Jongkaewwattana, and Terrell Barry, Department of Agronomy and Range Science, University of California, Davis.

• The average head rice yield for nearly 1,200 lots of rice for all varieties and locations in 1983 was 57.8 percent, or 5.1 percent higher than the 1982 average.
• The average grain moisture content at harvest in 1983 was 23.2 percent, which was 0.5 percent above the previous year. Variation in moisture content was smaller in 1983 than in 1982.
• The number of degree days between 65°F and 95°F was higher in 1983 than in 1982 in all locations.
• Panicle growth and development curves were established for the principal California varieties to determine the rate and duration of grain filling and its implications relative to grain uniformity.
• Differences were found in growth patterns within panicles among varieties. The varieties M-302 and M7 were more uniform in grain weights from different parts of the panicles than the varieties M-101, M-201, L-202 and California Belle.

RICE STRAW BURNING

Agricultural Burning Test Program

Les Fife, Fife Environmental, Fair Oaks, California.

• The fall burning program in the Sacramento Valley began September 28 and concluded November 9. During this 43-day period 230,315 acres were burned.
• Because of early rice harvesting in 1984, burning began earlier, with 67,617 acres burned between September 1 through September 27.
• The Air Resources Board received 74 complaints during the 27-day September burning period and 57 during the 43-day period after September 28. The number of complaints have increased each year of the test burning program but are still far below those received in 1980 prior to the test program.
• The 37 hours of smoke reported at airports at Red Bluff, Marysville, Sacramento Metro and Sacramento Executive during the fall burning program were the lowest since the program began in 1981.
• The 13 stations that monitor the coefficients of haze show a basin-wide average of 1.99. This compares favorably with the 3 previous years which had average coefficients of haze of 3.40, 2.74, and 3.25 for 1981, 1982, and 1983, respectively.
• The overall results of the 1984 fall burning program were mixed even though the air quality readings basinwide were the most favorable since the program began. Circumstances contributing to the increased number of complaints were communications breakdown, placement of burns in the wrong burning management zones, lighting damp fields, and too much burning in one area of the basin. Recommendations were made to correct these problems.