Rice Production Systems-77
 

 

 

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Project Leader and Principal UC Investigators

Improvement of Agronomic Practices for Rice Production

D.E. Seaman, UC Davis

B.W. Brandon

T.R. Woolsey

H.P. Wright

C.E. Turner

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Cooperative Extension Improved Rice Production Systems

D. Marlin Brandon, UC Davis

L.A. Post

K. Mueller

T. Pritchard

G.J. St. Andre

C.M. Wick

J.F. Williams

J.P. Guerard

 

Fertilization research helped solve the problem of crop rotation following rice, adding at least $18 million to $20 million to rice farm income in the Sacramento Valley in the past 6 years. This work has been of special value when the drought or market situation compelled us to grow other crops on some rice lands.

The productivity of rotational crops on old rice soils can be increased by placing phosphorus fertilizer near the seed at planting time. Note the difference between the phosphorus fertilized sorghum on the left and the control planting. Yield increases of more than 1, 000 pounds per acre have been recorded in Colusa County field experiments with crops such as barley, wheat, safflower, and grain sorghum.

 

Safflower immediately following rice is especially responsive to phosphorus placed close to the seed, as shown in the UC Cooperative Extension experiment. Banded phosphorus gives early vigorous growth of safflower (left) on old rice land, compared with poor growth where phosphorus is not provided. both plots received the same amount of nitrogen fertilizer.

 

Research showed that, usually zinc, not iron, was needed to correct adverse conditions in alkali rice soils. The "alkali" problem, cause by a zinc deficiency, appears in rice as chlorosis in seedling plants and partial loss of stand. Where zinc is needed, it was shown that relatively low rates of zinc fertilizer could be used, at a third of less the cost of commonly used zinc-contaminated commercial iron sources such as ferric sulfate and iron oxide. The savings to California rice growers since 1969 in reduced costs to control "alkli disease" are estimated at more than $2 million.

 

Field tests like this one in Colusa County have been used to establish critical nutrient values in soils and in rice plant tissue. UC rice fertilization research also has been directed partly toward the development of analytical tools to estimate fertilizer needs and to develop better methods of correcting deficiencies in rice plant nutrition. Two of these methods - preplant soil analysis and growing season rice tissue analysis - are now widely used to determine fertilizer programs for each rice crop. A rapid tissue test that growers can use in the field on growing rice plants should be available soon.

In this Sutter County experiment on the Tennis Ranch, CS-M3 in the foreground lodged at 150 pounds of nitrogen per acre. Short-statured Calrose 76 (background) and M7 (3rd label back) did not lodge. Better management of nitrogen fertilizer can produce higher yields in all new rice varieties. The new short-stature varieties Calrose 76, M7 and M9 are more responsive to nitrogen fertilizer. They lodge less and usually require higher nitrogen rates than the tall varieties for maximum yield. Limited experimental results indicate that the critical level of tissue nitrogen in short-stature varieties is similar to that of the tall varieties. Nitrogen fertilizer is utilized more efficiently by the short-stature varieties because of their superior genetic makeup. These rices will increase grain yields about 15 percent and decrease straw yields by 15 percent when fertilized with optimum rates of nitrogen.

 

Because of the importance of water in the production of rice, we have sponsored far ranging rice irrigation studies by UCD water scientists and engineers, Dr. D. W. Henderson, Dr. K.K. Tanji and Dr. W.O. Pruitt. Shallow water culture increases rice yield and should be used in growing the short rice varieties. Management techniques have been developed to ensure that the quality of the water we use and return to public streams is preserved. Water consumptive use by rice is only 3.5 percent greater than for a field of fescue grass. Any water over that actually required for growth of the rice crop is returned to the public waterways and underground storage for a variety of other public uses. The funding of water quality research has served as "seed money," subsequently bringing in sizeable federal grants for this purpose. UCD irrigation researchers have just begun a study of the turbidity problem in the Colusa Drain based on an Environmental Protection Agency grant.

 

Members of the Rice Research Board make it a point to personally visit on-going rice research projects. Here (1. to r.) Dr. L.D. Whittig, UCD; Mel Androus, manager, Rice Research Board; and Board member Francis B. DuBois tour Dr. K. K. Tanji's water quality research project in the San Joaquin and Sacramento valleys.

 

The Board has funded research to discover more efficient, energy conserving rice drying methods. UCD's agricultural engineer Dr. R. Paul Singh uses a new computerized dryer in his research. He is working on ways to recycle the warm air discharged from commercial dryers.

Obtaining nitrogen from the air in the style of legumes has been explored for Riceland use by UCD's Drs. D. W. Rains and S. N. Talley. A water fern, Azolla, reacts with a blue-green algae to fix nitrogen from the air. Research shows that it grows well in rice fields, suppresses weeds if started at the right time, dies before rice emergence, and releases nitrogen as it decays. It has potential to produce about half the nitrogen a rice crop needs, but its use would require new crop management techniques. The Board's support of this exploratory work has led to major support from other sources for its continuation.

 

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