Classroom Activities

Topics include :

• Historical perspectives.
• Parental germplasm and population formation.
• Plant breeding terminology and symbols.
• Genetic constitution of an open-pollinated population.
• Inbreeding.
• Introduction to quantitative genetics.
• Measuring quantitative variation.
• Heritability.
• Genotype x environment interaction.
• Molecular markers.
• Methods associated with breeding self-pollinated species.
• Inbreeding depression and heterosis.
• Methods associated with breeding cross-pollinated species.

Developing cultivars of small grains

We develop cultivars of wheat, oat, and triticale that combine overall agronomic superiority with disease, and insect resistance, and end-use quality. Between 25,000 and 50,000 head-rows are evaluated annually in our breeding nurseries.

In our wheat breeding program, we emphasize grain yield and end-use quality, but we have set an additional goal whereby N. C. State University-developed cultivars will not require routine applications of foliar fungicides to control the powdery mildew or leaf rust fungi. In addition, we have made progress in developing cereal leaf beetle-resistant cultivars that will eliminate the need for routine insecticidal applications to control this pest.

In the oat program we emphasize grain yield, test weight, and grain color suitable for the horse market. We have made progress in increasing the grain protein content of oats and are working on increasing the grain oil content to enhance feed value. In recent years, we have concentrated on the development of hull-less or naked oat cultivars. This novel oat sheds its fibrous hulls during the harvesting process, thus the hull-less oat grain is higher in protein and energy content relative to its hulled, or covered, counterpart.

Triticale acreage in North Carolina is small at present, but we are convinced that this species has potential for the state's small grain producers. We have observed in our breeding nurseries that triticale has high levels of disease and insect resistance and drought tolerance. Its grain has a high quality protein that makes it suitable for hog and poultry feed, and many cultivars produce abundant leafy growth in late winter and early spring with potential for grazing or silage production. We released our first triticale cultivar, 'Arcia' in 2001.

Investigating sources of disease resistance

The objectives of this program is to investigate sources of resistance to:

1. Powdery mildew, leaf rust, and Fusarium Head Blight (FHB) in cultivated and progenitor gene pools of wheat; and 
2. Crown rust in hexaploid progenitors of oat.

During the past six years we released 11 soft red winter wheat germplasm lines with resistance to powdery mildew. The sources of resistance were diploid and tetraploid common wheat relatives--Aegilops tauschii, Triticum monococcum sp. monococcum, T. monococcum sp. aegilopoides, T. turgidum sp. dicoccoides and T. timopheevii sp. armeniacum. This work is continuing with emphasis moving to leaf rust and Septoria glume blotch in wheat and crown rust in oats.

Southeastern wheat breeders, producers, and end-users are anxious that pro-active measures be taken to avoid a repeat of the Midwestern/North Central experience with Fusarium Head Blight or scab. We are involved in a cooperative evaluation program with Dr. Anne McKendry, University of Missouri, to evaluate winter wheat cultivars in the USDA's National Small Grains collection for resistance to this fungus. Current efforts are directed at accessions originating in Italy and The Balkans.

In addition, the annual Uniform Southern Soft Red Winter Wheat Fusarium Head Blight Nursery is coordinated from N. C. State. This nursery has nine public and private cooperators who evaluate advanced generation breeding lines for FHB resistance at locations from Louisiana to Virginia.

Genetics of powdery mildew resistance

We are investigating the genetics of powdery mildew resistance in 11 soft red winter wheat germplasms released over the past four years. Specifically, we wish to identify the number of different resistance loci involved, find molecular markers linked to the resistance alleles, and combine different resistance alleles into pyramids.

Genetics of cold hardiness in wheat

Investigations into the genetics of cold hardiness in three recombinant inbred winter oat populations are being conducted in the laboratoy and field. Specifically, we wish to identify AFLP ARD RFLP markers linked to quantitative trait loci controlling winter survival.

Genetics of Cereal leaf beetle

We are investigating the genetics of cereal leaf beetle resistance in a recombinant inbred population of wheat and to identify AFLP markers linked to resistance loci.