The trial was drill-seeded on April 30th at a rate of 150 lb/acre in a field planted with M-206. Only medium grain varieties were evaluated, which were replicated four times as 150 ft2 plots. Fertility and pests were managed by the grower in the same manner as the field. We harvested the trial on October 8th, and yield was determined by hand-harvesting a 15 ft2 area from each plot.
Results from the Delta location are shown in Table 1 and Figure 1 (advanced breeding lines omitted). Among the entries, M-206 is the most commonly planted variety in the Delta and across the state. It has good agronomic characteristics, consistent quality across different harvest moistures, and the highest average yield across varieties over the last four years. Among the newer varieties, M-210 is early maturing, has blast disease resistance, and would be a good option in the Delta, particularly on farms where blast has been observed. It has had the second highest average yield over the last four years. Some Delta growers also plant M-105, which is a very-early variety but is observed to be more susceptible to blast compared to M-206. In 2024, I did not observe, nor did I hear of blast being a problem in the Delta, and my colleagues in the Sacramento Valley have noted that it was a low blast year. While M-211 performed well in 2024, it is not as well adapted to cooler environments as M-210, has had variable performance over the last four years (Figure 1), and its quality tends to decrease below 18 percent harvest moisture. M-521 is also known as ROXY® rice and is oxyfluorfen resistant. While the variety is released, the herbicide technology has not yet been approved by the EPA and CA DPR. Statewide results of all eight testing locations will be available soon from the UC Rice Research and Information Center website.
Special thanks go to our cooperating growers and the CA Rice Research Board for financially supporting the trials. If you have questions about the trial or about Delta rice production, please don't hesitate to reach out to me, and good luck in 2025!
Table 1. 2024 Delta rice variety trial results. Data shown for commercial lines only.
Figure 1. Four-year Delta trial yield summary (lb/ac at 14% moisture).
