Upping the ante

Two new Clearfield long-grain varieties offer good yield potential and disease package.

• By Vicky Boyd,
Editor •

sunny bottoms tim walker

Sunny Bottoms (left) and Tim Walker of Horizon Ag check out a demonstration field of CLL16 and CLL17 near Stuttgart, Arkansas — photo by Vicky Boyd

Two new Clearfield long-grain varieties available commercially in 2021 will up the ante with high yield potential, good grain quality and strong blast resistance.

CLL16 is from the rice breeding program of University of Arkansas’ Karen Moldenhauer, while CLL17 is from Louisiana State University AgCenter rice breeder Adam Famoso. They will be marketed by Horizon Ag.

“Right now, we’re going to put some CLL17 in some situations up north, but we really want to focus on CLL17 being in Louisiana and Texas,” said Horizon Ag General Manager Tim Walker. “It’s just proven so much better down there and is more consistent down there. Based on our inventory, I’m going to be talking about CLL15 and CLL16 in Arkansas, Mississippi and Missouri.”

CLL16

The two varieties were available in 2020 mostly for seed production as well as a few strip or small-field demonstrations.
“We’ve had a lot of strips or fields that have harvested over 200 bushels an acre,” Walker said. “The majority of the strips we were harvesting were 200-220 dry at 12%.”

In University of Arkansas commercial rice trials at 12 locations in Arkansas, CLL16 averaged 206 bushels per acre, according to preliminary results.

Daniel Shannon and his father, Nolen Canon, had a large on-farm demonstration field of CLL15, CLL16 and CLL153 near Tunica, Mississippi, this season. The CLL16 cut about 240 bushels per acre green, Shannon said, citing yield monitor readings.

The CLL15 cut 201 bushels per acre and the CL153 cut 196 bushels per acre. All three were harvested the same day using the same combine, which had a self-calibrating yield monitor, and all three were managed the same.

Based on what he saw, Shannon said he’s excited about the new Clearfield variety. “It looked that much better, no joke,” he said. “I hope to see some more 16 next year if I can get my hands on it.”

CLL16 also was put to the lodging test with the remnants of several tropical storms passing through the area this season.

“It has very good standabilty,” Shannon said. “I was really impressed and cut very little of that whole block down. It stood right alongside the 153, and I can’t complain about that.”

In addition to strong yield potential, CLL16 also appears to have good grain quality, Walker said.

“The grain quality, I think, is going to be really good as far as the grain appearance,” he said. “It’s going to be on par for a grain appearance to our CL153 or Cheniere — some of those varieties that are very low chalk and are acceptable in the export markets.”

CLL116 has two blast-resistant genes ­— Pi-ta and Pi-ks ­— giving it a much stronger disease package than Diamond, a popular conventional variety from Moldenhauer’s program that lacks the genes.

CLL16 also is taller than some of the other Clearfield varieties, standing at 42 inches with more erect leaves.

Walker recommended seeding rates similar to other Clearfield long-grain varieties. Because of its erectness, growers could bump up the seeding rate about 5 pounds per acre without issues.

“I think CLL16 is going to definitely fit on the (Arkansas Grand) Prairie because of the taller plant type and you have more levees,” Walker said. “Right now based on the data, I can say that CLL16 has been more stable this year. We think a lot of it is going to have to do with planting dates. If you plant CLL15 early, I think 15 can run right up there with 16.”

CLL17

This new Clearfield variety has already shown its yield potential by having the highest production of any variety in LSU AgCenter Extension rice agronomist Dustin Harrell’s variety-by-nitrogen trials.

This allowed Walker and others to collect data on lodging and other issues to develop official grower recommendations.

In a 24-acre seed production field south of the AgCenter’s Crowley facility, foundation rice seed program director Rick Zaunbrecher said CLL17 yielded more than any other variety, coming in at 59 barrels ­— or 212 bushels — per acre. And the new variety was planted at a very low seeding rate to maximize seed production.

In Famoso’s day-of-planting trial, 12 varieties are planted at the H. Rouse Caffey Rice Research Station in Crowley every two weeks for a total of eight dates across the season.

When planted in the recommended window of March and April, CLL17 had the highest yields among all varieties. But its yields dropped off with the later planting dates past April, which were also affected by hurricanes Laura and Delta

With a height of about 39 inches, Famoso said CLL17 is a bit taller than the true semi-dwarf varieties LSU AgCenter has released in the past. CLL153, for example, is 2-3 inches shorter.

He said he saw a bit of lodging, particularly in the later fields and at higher nitrogen levels, “so that’s something we want to keep an eye on. Any of the lodging we observed was in the latter-planted rice and coincided with a weather event. The early stuff up until the storms was very good.”

Walker said he has seen similar high yields throughout the southern rice belt.

“All my trials show that CLL17 is outperforming and is well over 200 bushels per acre in Texas and Louisiana,” he said.
CLL17 has a grain size and translucency similar to CL111, an older Clearfield long grain that has drawn praise from local mills.

The jury is still out on CLL17’s ratoon yield potential. Hurricane Delta as well as other storms damaged most ratoon crops, clouding the variety’s true second-crop yield potential.

What next?

With the commercial introduction of CLL15 long grain and CLM04 medium grain in 2020 and the two Clearfield long grains for 2021, Walker said Horizon Ag will take a long, hard look in 2021 at its offerings.

“We need to figure it out. For our marketshare, we had so many varieties, and some of our varieties have gotten a bit stale,” he said. “CLL17 is a drastic improvement on yield over CLL153 and CL111. CLL17 also has equal or better yield potential than CL151, but it also has blast resistance.”

CL153 seed availability in 2021 will be much less than 2020, he said.