• By Vicky Boyd,
The Louisiana State University AgCenter showed off a number of promising varieties that potentially could be released in coming years during its recent first-ever virtual rice field day.
The annual event, held at the university’s H. Rouse Caffey Rice Research Station near Crowley, was changed to an online format this year after the coronavirus pandemic precluded large get-togethers.
Included in the conventional breeding tour were two conventional long-grain lines, a medium-grain line, a Clearfield long-grain line and four Provisia lines.
One of the potential releases, identified in the trials as LA2140, is a long-grain variety with Cheniere and Mermentau as parents, said LSU AgCenter rice breeder Adama Famoso. It is similar to Cheniere — the most widely grown conventional variety in Louisiana — in height and maturity.
One of the main differences is LA2140 has a more typical Southern long-grain amylose content whereas Cheniere has slightly higher amylose. A natural occurring starch, amylose influences rice cooking quality. The higher the amylose content, the more apt the rice is to cook fluffy with separate kernels.
“Cheniere is a very high grain quality package quality type of rice,” Famoso said. “LA2140 is a little lower in grain quality in terms of chalk. It’s slightly more chalky, and it’s a slightly shorter grain but still very good grain quality.”
What’s most exciting about the line, he said, is it has shown a 5% to 10% yield advantage over Cheniere in four years of trials. The variety will likely be released at the end of the year and be grown for seed production in 2021. It would then be available commercially in 2022.
LA2207 is another variety similar to Cheniere in grain quality, chalk and grain size. It has an intermediate amylose cook type similar to LA2140. What sets LA2207 apart is it contains the Pi-ta blast-resistance gene and has shown very good blast resistance in trials. In Dr. Don Groth’s disease nursery, it also has shown good resistance to bacterial panicle blight.
In the past two years of multi-location testing, LA2207 has been on par with LA2140, showing a 5% to 10% yield advantage over Cheniere. Famoso said they will see how it performs this year in Louisiana and neighboring states.
“This is another very promising conventional line to potentially follow up to LA2140,” he said.
LA2227, a cross between the medium-grains Neptune and Jupiter, has performed very well in three years of trials. In 2019, LA2227 had average yields similar to Titan and Jupiter, the two most widely grown medium grains in the South. But in 2018, it had an 8% to 10% yield advantage over Jupiter.
“So we’re hopeful we will see that yield advantage in 2020,” Famoso said.
LA2227 is a couple inches shorter than Titan and matures a couple days later than Titan but about three days earlier than Jupiter.
It has improved chalk compared to Jupiter but still maintains the high milling of Jupiter.
Although LA2227 showed similar blast resistance as Jupiter in the LSU disease nursery, it does contain the Pi-z blast-resistance gene, which Jupiter does not.
In some years, Famoso said, it may offer improved blast resistance compared to Jupiter.
After this third year of multi-location testing, he said they would have a much better idea of the line’s future.
CL2026 is a Clearfield long-grain variety with grain quality on par with CL153, along with very good milling. Like the most recent Clearfield releases, CL2026 contains the Pi-ta gene for blast resistance.
It has a maturity between CL153 and the shorter-season CL111.
This is the third year of multi-location testing for CL2026. In 2019, it was the top-yielding conventional variety.
“We’ll see how this line does this year,” Famoso said. “It’s another one we potentially might begin purifying and increasing in Puerto Rico if it continues to perform as it has the last few years.”
Four Provisia lines
Famoso also is looking at four sister lines that resulted from a cross of PVL01, the first commercial Provisia long-grain variety, and Catahoula, an early, semi-dwarf, long-grain variety with excellent yield potential and very good milling.
All four have the Pi-ta blast-resistance gene, unlike PVL01 and PVL02. Blast resistance was one of the priorities when breeders started developing Provisia rice.
All four lines were amplified and purified during the 2019-20 winter in Puerto Rico. They currently are in 1-acre seed increase blocks near Crowley and are being tested in parallel in Louisiana and neighboring states.
PVL2074, probably the most promising of the four, has very high grain quality and low chalk that falls between PVL01 and PVL02, Famoso said.
PVL01 has a long, slender kernel that averages 7.3 millimeters, making it more susceptible to damage during milling. PVL02 falls on the short end of long-grain kernel size at about 6.5 mm. PVL2074 falls between that with about a 7.1 mm grain. Most standard long-grain kernels average about 6.9 mm.
But like PVL02, PVL2074 has low chalk, averaging about 5% in 2019. In trials, it also has consistently outyielded PVL02.
“At the end of this year, we’ll decide whether we’re going forward with any of these lines and which one,” he said.
Video courtesy LSU AgCenter