Rice Variety Trials, 2014

 

Project Leader

Bruce Linquist, UCCE rice specialist, Dept. of Plant Sciences, UC Davis

Sixteen on-farm rice variety evaluation trials were conducted throughout the rice growing regions of California in 2014 by UC Cooperative Extension scientists in cooperation with plant breeders at the Rice Experiment Station (RES). Standard varieties were compared with preliminary and advanced lines in these tests to measure performance across a range of environments, farmer practices, and disease levels.

Six similar tests were conducted at RES in Biggs, two from each maturity group. Average yields across varieties and locations in the advanced-line tests ranged from 9,030 pounds/acre in the very early trials to 9,520 pounds/acre in the intermediate-to-late tests. In the early tests the advanced lines average yield was 8,790 pounds/acre.

Field preparation was completed earlier than normal because of the relatively dry spring. Planting was completed in a timely manner. However, several areas experienced delayed water deliveries in 2014, resulting in large areas being planted in a short period of time. Several advanced lines in 2014 produced high yields and demonstrated advances toward other important breeding goals, such as disease resistance, grain quality, and specialty types. Testing advanced and preliminary lines under a variety of conditions remains a critical aspect of releasing varieties adapted to changing cultural practices, markets, and pests.

Rice variety evaluations

Eight uniform advanced breeding line trials and eight preliminary breeding line trials were conducted throughout the major rice producing areas of California. The RES rice breeders conducted six additional tests—two from each of the three maturity groups. Many of the experimental lines have been tested and screened in previous years and advanced for further testing. Agronomic performance summaries follow.

VERY EARLY MATURITY

Seven advanced breeding lines and nine commercial varieties were compared in four very early advanced tests. The preliminary tests included six commercial varieties and 30 preliminary lines evaluated in separate tests at each location. Commercial varieties at each location included S-102, A-202, CA-201, CH-201, CH-202, CM-101, M-104, M-105, M-202, M-203, M-205, M-206, M-208, M-402, and L-206.

Grain yields in the advanced tests averaged 9,030 pounds/acres overall, 8,530 pounds/acre at RES, 9,210 pounds/acre at Sutter, 9,420 pounds/acre at Yolo, and 9,010 pounds/acre at San Joaquin. The three highest yielding entries on average were advanced medium grain line 08Y3269 (9,670 pounds/acre), premium quality medium grain line 11Y2022 (9,630 pounds/acre), and blast-resistant medium grain line 12Y113 (9,620 pounds/acre). Top yielding commercial varieties included M-206, M-205, M-104, and L-206. Averaged across locations, yields for lines in the preliminary tests ranged from 6,160 pounds/acre to 10,320 pounds/acre.

Average grain moisture at harvest and lodging increased (0.6% and 20%, respectively), while number of days to 50% heading decreased by two compared to 2013. Seedling vigor and plant height were essentially the same as in 2013. Field preparation was completed earlier than normal. Planting was completed within the average time frame, although several districts experienced delayed water deliveries. This resulted in large areas being planted in a short period of time. Relatively dry weather throughout the growing season resulted in a timely harvest and reasonably good grain quality.

Comparing commercial standard entries over a five-year period and across locations, M-206, M-104, and L-206 were the highest yielding varieties at 9,318 pounds/acre, 9,091 pounds/acre, and 8,944 pounds/acre, respectively.

EARLY MATURITY

Eight advanced breeding lines and eight commercial varieties were compared in four early advanced tests. Preliminary tests included eight commercial varieties and 31 preliminary lines evaluated in separate tests at each location. Commercial varieties at each location included S-102, A-201, CH-201, CH-202, CM-101, M-105, M-202, M-203, M-205, M-206, M-208, M-402, A-202, CA-201, CT-202, and L-206.

Yields in the advanced lines averaged 8,790 pounds/acre overall, 8,510 pounds/acre at RES, 9,060 pounds/acre at Butte, 8,940 pounds/acre at Colusa, and 8,650 pounds/acre at Yuba. Advanced long grain 13Y1073 was the highest yielding entry (9,900 pounds/acre) averaged over four locations in 2014. Advanced experimental long grains 11Y1005 and 11Y1008 and the blast resistant medium grain line 12Y113 yielded second, third, and fourth, respectively. Top yielding commercial varieties included M-206, L-206, M-205, M-202, and CH-202.

Average days to 50% heading ranged from 82 days at the Rice Experiment Station and Butte to 86 days at the slightly cooler Yuba County site. The commercial standard M-206 headed at 80 days at Biggs and 84 days at Yuba. The average yield of M-105 decreased 3.3% compared to 2013. Nine experimental lines averaged significantly higher yields than M-105 in preliminary tests.

Over a five-year period and across locations, L-206 was the highest yielding commercial variety at 9,561 pounds/acre, followed by M-206 at 9,543 pounds/acre and M-205 at 9,509 pounds/acre.

INTERMEDIATE-TO-LATE MATURITY

Four advanced experimental lines and seven commercial varieties were compared in three intermediate-to-late tests. Preliminary tests included seven commercial varieties and 18 preliminary lines evaluated in separate tests at each location. Commercial varieties at each location included CM-101, CH-201, CH-202, Koshihikari, M-105, M-202, M-203, M-205, M-206, M-208, M-401, M-402, L-206, and A-202.

Yields in the advanced lines averaged 9,520 pounds/acre overall, 10,220 pounds/acre at RES, 8,820 pounds/acre at Glenn, and 8,590 pounds/acre at Sutter. The 2014 advanced over-location yield increased 650 pounds/acre (7%) compared to the 2013 season average. The average yields at the Rice Experiment Station increased 660 pounds/acre and increased 200 pounds/acre at Glenn compared to the 2013 season. M-205 was the highest yielding commercial variety (9,730 pounds/acre), ranking fifth overall. L-206 and M-402 were the next highest yielding commercial varieties. The premium quality medium grain entry 11Y2183 was the highest yielding advanced entry across locations at 10,350 pounds/acre.

Average days to 50% heading decreased four days compared to 2013. M-401 and Koshihikari were the latest varieties at 108 and 113 days, respectively. Over a five-year period and across locations, L-206 is the highest yielding commercial variety in this group at 9,512 pounds/acre, followed closely by M-205 at 9,495 pounds/acre. L-206 and M-205 produced 107% and 105% of the yield of M-202 over the last five years.