Getting rice research off the station and into a “real” field is key to pushing rice genetics, says James Gibbons, a rice breeder at the Extension Rice Research and Extension Center at Stuttgart, Ark.
“It's very important for plant breeders to be able to see how these varieties perform under true farming conditions. If we do trials strictly at an experiment station, we might not get the reaction to sheath blight here and kernel smut there, and we might miss some other disease or problem in the state,” says Gibbons, who spoke at the Prairie County Extension farm tour.
“About half the rice we grow is exported and half stays within the country. In the export market, we compete with Vietnam and Thailand, and India is now a big exporter. Our competition is formidable, and that's yet another reason we must continue to produce rice with high yields, lower production costs and high quality.”
At a field day stop just outside Des Arc, Ark., both Gibbons and Extension plant pathologist Rick Cartwright discussed what they'd found in working with different varieties. Below are their comments.
Clearfield 141, 121 & 161
These are the three Clearfield varieties. The 141 is based on Maybelle, 121 is based on Cocodrie, and 161 is based on Cypress, says Gibbons.
“The yield potential on these lines is moderate — at least on our plots. The 161 tends to produce better yields and is more consistent for us. Our thinking is 161 will be the future of Clearfield, although you must watch sheath blight on it. It can be managed, but on a field that he's pushing and fertilizing, a farmer probably needs to just budget a fungicide in. It's that susceptible, and it's likely farmers won't be scouting for sheath blight as much as simply pulling the trigger on an early spraying. Ten or 12 ounces of Quadris ought to hold it,” says Cartwright.
The good part of 161 (a variety that tillers a lot) is that it's not very susceptible to blast. It may have a touch of kernel smut — but nothing like Cypress. And Cartwright says it's pretty tolerant to straighthead.
121 and 141 have tolerance to Newpath herbicide, so they can be hurt if sprayed improperly. 161 has true resistance to Newpath, so it's more durable in a herbicide scheme.
“You can't really burn or stunt 161 with Newpath. In working with so many people, I see all kinds of rates accidentally put out on our demonstrations. We had an instance where I had someone spray Newpath on a demonstration and the calibration was messed up. We figure the field of Clearfield varieties ended up with a 12X rate. It killed every plant of 121 and 141 we had, but the 161 wasn't even fazed,” says Cartwright.
The hybrid long grains XL7 and XL8 were released last year as very early-maturing varieties. XL8 matures later like Drew or LaGrue. The yield potential of XL8, under proper management, is extremely high.
“You need to follow RiceTec's management plan on these hybrids because the management of hybrids is different than that on conventional varieties. Obviously, they don't use as much seed — maybe 35 pounds per acre. The nitrogen recommendations for these two hybrids are higher — about 120 units — than for the older XL6,” says Gibbons.
Once you go up on nitrogen — whether the variety is a hybrid or conventional — diseases become more of a factor.
“There are circumstances where we may treat XL7 and XL8 with fungicides to control moderate sheath blight and kernel smut. These two are resistant to blast, but they may need a bit of spraying,” says Cartwright.
This as-yet-unreleased variety has an advantage in its earliness. Farmers may be able to conserve water while taking advantage of its reduced seeding rate.
“For farmers interested in planting after wheat, RU1093's extra-short maturity date may allow it to be planted after wheat. There's some interest from consistent wheat producers in that. It has resistance to blast, which is a concern when planting rice late. We hope RU1093 will make it through the program and give farmers another variety to plant late on levees,” says Cartwright.
The variety's yield potential — at least on Cartwright's plots — has been, “good for an ultra-short long-grain. I'm getting 150 to 170 dry bushels and that's unusual for a rice that's 70 days to 50 percent heading.”
Cocodrie, a variety out of Louisiana, was planted on about 28 percent of Arkansas acres this year. The variety has excellent quality and a good disease package.
“On Cocodrie, sheath blight has been a problem — although it's not hard to manage for. This variety is holding up pretty well for a semi-dwarf. We're using a lot of reduced fungicide rates on Cocodrie even though it's a semi-dwarf. Its main enemy is straight head,” says Cartwright.
Francis is a variety out of the rice breeding program in Stuttgart. It's very high-yielding and is the same type variety as LaGrue or Wells.
“Francis is a super-yielder, has good milling quality and is good on straighthead. But it does have some disease weaknesses. As with LaGrue, those weaknesses are manageable, and with such high yields you have some comfort in making management decisions,” says Cartwright.
He says farmers will probably want to pick and choose where to put Francis.
“It's a racehorse and you don't want to run the race on a track full of potholes. Francis is susceptible to blast and kernel smut. It's probably got a similar susceptibility as LaGrue. But it can be managed in a good, productive field. Just don't put Francis on cotton soils that aren't easily watered — that's where blast will get you.”
As far as high-yielding, blast-tolerant varieties, Ahrent is a really good one, says Gibbons. Another line — RU1124 — is a blast-tolerant semi-dwarf that researchers are working with although it isn't in foundation seed yet. “While Francis may be the racehorse fit for a nice, smooth track, Ahrent is a variety that can compete on any track. It has consistently good yields and good quality over many environments. It has good disease resistance to blast and is pretty tolerant of kernel smut,” says Cartwright.
Bengal is the number one medium grain in the South. It's being grown on about 10 percent of Arkansas' rice acreage this year.
“Medium grains are almost a specialty rice because they're used in a lot of food processing. Quality is, therefore, very important, and Bengal is one that's accepted fairly well by mills and processors like Kellogg. Uniformity is a concern they have, but I'm not sure there's a heck of a lot we can do about that,” says Gibbons.
This unreleased variety is a cross with Bengal. It's a semi-dwarf very similar to Bengal in tillering and yields (although it has yielded slightly higher than Bengal in the South). “It has a very slight disease package advantage: when Bengal gets a 7 rating for blast, this one will get a 6. So it's still susceptible. RU1151 is in foundation fields this year. We'll make a decision on release sometime this winter.
“We have other medium grains in the pipeline. Grain size is very important with medium grains. We've brought in some big-grained varieties from Italy to incorporate into our program,” says Gibbons.
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