Ten Wheat Research Findings From Across the Nation

Over 50 research projects from wheat plant development to marketing are outlined in a published proceedings booklet of the 4th Annual National Wheat Industry Research Forum, held earlier this year, and sponsored by the National Association of Wheat Growers and the Wheat Industry Resource Committee. The proceedings may be obtained through the NAWG office, ph. 202-547-7800.

Both the National Wheat Industry Research Forum and its proceedings are sponsored in part by the wheat checkoff in North Dakota, South Dakota, and Minnesota, managed respectively by the North Dakota Wheat Commission, South Dakota Wheat Commission, and the Minnesota Wheat Research and Promotion Council.

Following are some of the research findings.

Anticipating Crop Stresses
A study conducted on a soft white wheat field in Idaho indicated that satellite imagery can predict nitrogen deficiency or stress in wheat as good or better than a chlorophyll meter.  Near infrared information collected through multispectral aerial and satellite imagery collected in-season allows early detection of stresses in a crop, as much as ten days prior to visible manifestation. This lead time gives a producer who utilizes this technology the ability to anticipate and correct problems, according to Kurt Harman and Jeremy Sadler of Land View Systems, an Idaho-based commercial provider of the technology.

No-till Favorable for Holding Carbon
Many scientists believe that an increasing level of carbon in the atmosphere contributes to global warming, which may lead to new industry regulations to control carbon emissions.  In time, this could result in profit opportunities for farmers, because it may be less costly for some companies to pay farmers to hold or sequester an offsetting amount of carbon in the soil, rather than revamp their own operations. A study at the University of Kentucky concludes that the continuous application of no-till soil management causes changed conditions in soil physical quality (greater bulk density, more continuous porosity, loss of larger pores in favor of smaller ones) that favor greater soil moisture retention and carbon sequestration in cereal-based rotations.

Scab And Plant Residue Management
Since the fall of 1999, North Dakota State University has been conducting a study to compare the decomposition rates of plant residue left on the soil surface to residue that is tilled under, and the presence of the Fusarium fungus in the residues. The objective is to develop strategies to accelerate the displacement of Fusarium in the soil. 

Preliminary assessment indicates that buried residue is decomposing at a faster rate than residue left on the surface.  In the first year of field incubation, nearly all corn residue was decomposed while 20% of the barley and wheat residues were present in bags of plant residue buried in the soil. However, 30% of the corn and wheat surface residues and 50% of the surface barley residue remained over the same time period. Nitrogen fertilizer slightly enhanced the decomposition rate. Fusarium populations appear consistent with the level of residue present. Data collection will continue until the fall of 2001.

Grass Control Herbicides Can Affect Durum Quality
In NDSU studies conducted near Prosper and Langdon in 1999 and 2000, Achieve, Assert, Discover, Paramount, and Puma caused little to no visible injury to durum wheat varieties evaluated. Avenge caused only slight injury to Ben, Maier, Munich, and Plaza, but caused 60% injury to Belzer, 43% injury to Lebsock, and 37% injury to Mountrail, averaged over environments.  The level of injury varied with environment.  Avenge is more phytotoxic during hot and humid conditions than during cool and dry conditions.

Plant height at maturity, days to heading, and grain yield depended on herbicide treatment and variety. Avenge reduced the height of Belzer, Mountrail, Lebsock, Plaza, and Ben.  Similarly, Assert reduced the height of Belzer and Lebsock; Discover reduced the height of Belzer, Lebsock, and Plaza; and Paramount reduced the height of Maier.  Avenge delayed heading of all seven varieties.  Heading was delayed an average of 1.3 days for Belzer, Lebsock, and Mountrail and 0.7 days for Ben, Maier, Munich, and Plaza. Assert delayed heading of Belzer 0.8 days and Maier 0.5 days; Discover delayed heading of Belzer 0.6 days; and Puma delayed heading of Lebsock 0.5 days.

Avenge reduced the yield of Belzer, Lebsock, and Mountrail; Assert reduced the yield of Mountrail; Discover reduced the yield of Belzer and Munich; Paramount reduced the yield of Maier; and Puma reduced the yield of Munich. Yield reduction did not relate to visible injury.  Yield reductions with Avenge were 22% for Belzer, 10% for Lebsock, and 14% for Mountrail, which were smaller than their corresponding visual injury ratings.  These results indicate partial recovery of durum wheat.  Other herbicides reduced yields without causing visible injury. For example, Discover reduced the yield of Belzer 8% and Munich 10% but had injury ratings of 1% or less.

Variety by herbicide interaction was not significant for any of the kernel or semolina properties tested.  Kernel weight and size was reduced by Avenge but was increased by Assert and Paramount. All herbicides, except Achieve, reduced protein content of the whole grain and semolina.  Protein quality and yellowness of semolina was not affected by herbicides.

New Method for Quickly Testing In-Field Sprout Damage
Grain elevators and flour mills often use the Falling Number test to analyze wheat for sprout damage, which can seriously affect the quality of bread and other finished products. WheatRite is a new, eight-minute test kit that can be used to determine sprout damage in the field, allowing the producer to harvest sound wheat apart from sprouted damaged sections.  The test is self-contained and may be run without any technical expertise or instrumentation. Results correlate to Falling Number values, according to a study by the American Institute of Baking in Manhattan, KS. (For more product info, contact Patricia Jackson, ph 1-800-338-4381 Ext. 49)

Partial Waxy Durum Offers Potential
Researchers at NDSU are studying the end-use performance of full and partial waxy durum, which has a lower starch content that may be valuable in the production of some types of Asian noodles. Results indicate that full waxy durum wheat is unsuited to pasta production because of higher cooking loss and undesirable texture (softness). However, partial waxy durum offers great potential because of higher firmness, lower water absorption and lower cooking loss.

Seeding Rate Effects on Stand Establishment and Yield
In a study of soft red winter wheat varieties in Kentucky, the low seeding rate/final stands (less than 25 plants per square foot) yielded similarly to higher seeding rate/final stands (25 or more plants per sq. ft). This demonstrates the remarkable compensatory ability of the wheat plant. However, this does not imply that low seeding rates should be utilized and that similar results would be obtained. Other factors need to be considered as well: For example, varieties used in this study have good tillering capacity, and varieties with less tillering capacity may not perform as well at low seeding rates. Also, weather during this study was conducive for tiller development and plant growth, whereas adverse growing seasons would hinder plant growth and development and thinner stands would not perform as well.

How Perfect Do Wheat Stands Need To Be?
A study is underway at the University of Kentucky to better understand the yield effect of gaps in a wheat stand. Only one year of results is compiled, but thus far, the study indicates that wheat stands do not have to be near perfect for high yields. Skips in the stand that comprise as much as 10% of the area will still yield as well as a stand with no skips.

Conventional Till Vs No-Till Wheat
A study at the University of Idaho indicates that no-till benefits of soil and water conservation, soil improvement, and lower inputs take time to accumulate.  The challenge of no-till to obtain an equivalent yield to conventional till is great, especially in the early years of no-till adoption. Although yield levels in this study were lower in no-till than conventional till, that difference could be attributed to the crops following winter wheat, more weed competition, and cooler soil conditions, especially during establishment. Most of those limitations can be overcome with good management practices and time. The cool soil conditions could also be compensated in some growing seasons with increased soil moisture availability in no-till. Variety selection appears to be important for successful no-till production because of variety performance differences between tillage treatments.  The adaptability of varieties to no-till was different in this study and further evaluations will provide better comparisons for selection of varieties for tillage-system specific growing conditions.

Impact of Pre-Harvest Herbicides on Wheat
A study at NDSU in 1999 and 2000 looked at the impact of pre-harvest applied herbicides on harvest date and factors related to crop dry-down, grain yield, grain quality, and seed viability. Treatments analyzed were glyphosate-ipa, glyphosate-tms, glyphosate-ipa + dicamba, glyphosate-ipa & 2,4-D ester, paraquat, metsulfuron + 2,4-D ester, and dicamba. Treatments were applied at 50% grain moisture and at physiological maturity (PM) to Parshall spring wheat grown at Langdon and Prosper.

All treatments investigated can be applied at PM to hard red spring wheat without negatively impacting yield or test weight. Non-selective herbicide treatments applied prior to PM will reduce yield and test weight; however, the selective herbicide treatments applied just prior to PM do not measurably impact yield or test weight.  The herbicide treatments containing glyphosate applied prior to PM reduce straw strength, and seed viability under certain conditions.