New wheat variety introductions reduce stripe rust losses

During the past three years, stripe rust has been a serious problem for California wheal growers. Several varieties introduced from Mexico under the continuing University of California cereal variety improvement program have been found to provide some protection from the disease. In California tests these varieties produced excellent yields in the presence of stripe rust and in general have equalled established California varieties in yield and agronomic characteristics when stripe rust was not a problem. Although tests in cooperation with the California milling industry have shown the re. sistant or tolerant Mexican varieties to be somewhat deficient in quality, they can be used when they meet the standards normally required by the milling industry. These deficiencies apparently are no greater than those existing in currently used California varieties. Until more information on their general acceptability is available, production of these varieties probably should be limited to districts with recurrent heavy losses frcm stripe rust. Programs to develop varieties which are resistant to stripe rust and more acceptable in other characteristics are underway.