Hornbeck Seed Company's extensive soybean breeding program continues to produce outstanding varieties for the Mid-South, area growers were told at the DeWitt, Ark., company's annual field day.

Both Roundup Ready and conventional varieties offer a broad range of characteristics to fit growers' needs, said soybean breeder James Thomas.

“Although there has been widespread adoption of the Roundup Ready technology, we will also continue our strong breeding program for conventional varieties. This will allow us to maintain an unencumbered germplasm bank for developing new varieties and will provide us parent seed for use in our crosses.”

At its 125-acre Arkansas operation, Hornbeck had 45,000 progeny lines this year, Thomas noted — “each one a potential new commercial variety.” Of that total, 20,000 were conventional varieties, the rest Roundup Ready.

Selections in replicated trials at 18 locations from Louisiana to Illinois are made first for yield.

“If a progeny line doesn't equal or better the yield from our check variety, we throw it away. We want only the highest-yielding selections to go into our replicated trials.”

About 3 percent to 6 percent of first-year progeny lines are kept for further trials, and that number is winnowed down in succeeding years, with only the top performers making it to commercial release.

Resistance to disease is also a major consideration in Hornbeck's breeding program, Thomas said.

“We've got a lot of disease resistance in our material; the goal is to get as much resistance as possible to as many diseases as possible without giving up yield.”

In addition to conventional and Roundup Ready varieties, the company also offers soybeans with the CystX technology, which provides complete genetic resistance to all known U.S. races of the soybean cyst nematode (SCN). The pest, considered by many the number one yield-robber for soybeans, resulted in 1998 U.S. losses estimated at $1.67 billion.

Varieties in the Hornbeck Seed Company lineup include:

  • R3980, a new Group III Roundup Ready soybean that is “an excellent choice” for early planting in Arkansas, Missouri, Mississippi, Tennessee, and north Texas.

  • R4310, a new Group IV Roundup Ready soybean for early planting, with a “tough soils disease package.”

  • R4622, a mid-Group IV Roundup Ready with moderate resistance to SCN races 3 and 14 and very good field tolerance to Phytopthora root rot; excellent tolerance to sudden death syndrome (SDS) and frogeye leaf spot. The indeterminate, thin plant is best planted in narrow rows and offers very high-yield potential on most soil types.

  • R4660, a Group IV Roundup Ready that performs well following wheat. It has an excellent disease package and SCN resistance.

  • R4820, a new late-Group IV Roundup Ready offering “tremendous yields, with a moderate disease package.” In 1999, it was the highest-yielding line at 15 locations and in 2000 had the highest overall average of any variety tested.

  • R4920, a late Group IV Roundup Ready that is “very high-yielding over a wide range of soil types, and performs very well after wheat where adequate moisture is present.”

  • R5101, a new early Group V Roundup Ready with standability that favors wide rows for early, quick canopying, and good performance on heavy clay soils.

  • R5420, a new high-yielding Group V Roundup Ready with an excellent disease package for problem areas and excellent seed-holding capacity for delayed harvest conditions.

  • R5422, a mid-Group V Roundup Ready, that includes resistance to Southern and peanut root-knot nematodes and SCN races 3 and 14 moderate, as well as good field tolerance to Phytopthora and SDS. The determinate, narrow plant type is adaptable to 30-inch rows or less and has very high yield potential on most soil types.

  • R5588, a Roundup Ready mid-Group V variety with an excellent disease package that makes it a good candidate for Phytopthora soils, and resistance to stem canker and frogeye leaf spot.

  • R5620, a new mid-Group V Roundup Ready with high yields across a wide range of soil types, on wide or narrow rows, with SCN resistance.

  • R5820, a new late Group V high-yielding Roundup Ready with resistance to SCN races 3, 14, and 6 and stem canker, with good tolerance to aerial blight, and very good field tolerance to Phytopthora, SDS, and frogeye leaf spot. “A great no-till variety on any row spacing.”

  • R5920, a Group V Roundup Ready, high-yielding variety with an excellent disease package that does well in narrow rows — “a great choice for growers to spread out their harvest.”

  • R6020, a Group VI high-yielding Roundup Ready that adapts to a wide range of soil types and performs very well following wheat, with adequate moisture. “A good narrow row variety that enables growers to spread their harvests.”

  • 4891, a conventional Group IV that is “a yield leader, with excellent early growth and quick canopy.” Although susceptible to SCN, it has outperformed SCN-resistant varieties in yield tests over a three-state area. Responds very well to irrigation.

  • 4944CX, a late Group IV conventional CystX variety, resistant to all known races of SCN, offering very high yields on cyst-infested soils; indeterminate, bushy type works well with any row spacing.

  • 5812, a new conventional Group V with resistance to SCN, stem canker, and frogeye leaf spot. It performs well on high chloride soils and is “great double-crop choice.”

  • 5990, a top yielding, late Group V with outstanding resistance to stem canker, frogeye leaf spot, and Southern root-knot nematode; does well for both double-crop and full-season programs, with extremely fast canopying that “makes it a great choice following wheat.”

  • 5991, a Group V with an excellent disease package, delivers top yields on heavy clay soils where water stress can be a problem. It has topped trials on lighter soils where SCN can limit yields.

  • 6600, a Group VI “that can stand heavy disease pressure,” with excellent resistance to sudden death syndrome, stem canker, frogeye leaf spot, and SCN — plus high yields.