Choosing the right wheat variety, or the misfortune of not selecting the right variety, has an impact on agronomic management decisions during the entire season. It can have even greater influence on crop marketing and potential profitability. The difference in yield from highest to lowest yielding variety in the Kern County test was 4,500 pounds per acre or more than $300 per acre difference in potential profit.
To a large degree, a variety's genetic pedigree controls grain quality and yield potential. Varieties differ in their resistance to diseases that are common in California such as stripe or leaf rust, powdery mildew, barley yellow dwarf and septoria tritici blotch. They differ in their adaptability to the different climatic conditions and season length that occurs in California. They also differ in maturity, straw strength and end use qualities. New varieties are introduced yearly that have better qualities or higher yield.
Trials at 12 sites
University of California Cooperative Extension advisors and specialist conduct trials at 12 sites throughout the state to evaluate yield and other agronomic traits of commercially available varieties and advanced breeding lines. Forty-one common wheat and triticale varieties and 29 durum wheat varieties were tested in 2004. Multi-year, multi-location tests provide the best information on yield stability and potential. The multiple environments also provide an excellent opportunity for rating other agronomic traits. Relative yield, how one variety compares to another, may change from year to year. That is why it is critical to look at long-term data.
About 605,000 acres of common wheat were grown in California last season. Three varieties accounted for two-thirds of that acreage. Summit was planted on more than 210,000 acres because of its good disease resistance. Acreage of planted varieties is very different from a couple of years ago. Other advanced lines, which may become varieties, offer higher yield potentials, improved disease resistance and good baking characteristics.
Durum wheat acreage is around 117,000 acres. The end-product use of durum wheat semolina demands a high quality, high protein grain. Nearly half of all durum acreage is one variety, Kronos. In 2004, Kronos yielded very well and has good disease resistance.
A newly released durum variety, Oro, was the highest yielding durum variety in the Kern County test. While many varieties are available, care needs to be taken to select the best variety for one's farming operation. Results from the Kern County wheat variety test and other pertinent varietal information can be obtained from the UC Cooperative Extension Office or on line at http://agric.ucdavis.edu/crops/cereals/cereal.htm.