Replacement of Growth Chambers

Introduction.

The pathology program at KSU-ARCH is the only wheat virology program in Kansas focused on the identification and development of resistance in wheat to Wheat streak mosaic virus (WSMV), identification of new viruses of wheat, and investigating resistance mechanisms. In these endeavors the pathology program is very highly integrated with the wheat breeding and entomology programs at KSU-ARCH. Recent achievements of this integration with the breeding program concerns the first release of a wheat line KS03HW158 with temperature-sensitive resistance to WSMV. In addition, the program has been a leader in the detection and characterization of new viruses found infecting wheat in Kansas. This proposal requests support for the replacement of the second of four critical temperature-controlled growth chambers (originally purchased in 1974 for which we can now no longer find replacement parts) that are used in identifying and developing these types of resistance to WSMV, and for use in other studies related to viruses infecting wheat in Kansas.

Rationale and Significance.

Each year losses to disease in wheat range from about 13 to 15% of the crop. Of these collective disease losses, WSMV has an average loss of approximately 2% but can account for over one-half of the disease losses in some years. The continued efforts into identifying and developing sources of temperature-sensitive resistance similar to KS03HW158 should allow for the continued development of additional wheat cultivars resistant to WSMV, providing market improvement by giving Kansas wheat producers improved profits. Of importance is the constant need to be aware of new viruses found infecting wheat in Kansas, which occurred this year when we isolated a new virus from wheat that has not been previously identified in the United States or elsewhere in the world. Currently, the name Triticum mosaic virus (TriMV) is being proposed for this virus. Unfortunately, TriMV infects our advanced wheat lines with resistance to WSMV.

Procedures /Methodology.

Replacement growth chambers will be used to continue screening the world wheat germplasm at multiple temperatures to identify additional sources of temperature-sensitive resistance to WSMV. These chambers will also be used to screen progeny of crosses made in the wheat breeding program made from wheat having been identified as having resistance under mechanical inoculation with WSMV. The chambers will also be used in experiments to determine the response of advanced wheat lines with resistance to WSMV at different temperatures to infection by TriMV and in further biological characterization of this new virus.

Related Current/Previous Research.

The identification and development of WSMV resistant wheat and related research has been in progress for many years and the program at Hays is the only location where this occurs. This research has identified tolerance and temperature-sensitive resistance in wheat to WSMV. As a result, wheat germplasm leading to the development of the WSMV resistant wheat line KS03HW158 was identified and developed. Over 1,500 germplasm lines from the world collection have been screened for temperature-sensitive resistance using the growth chambers and additional sources of resistance have been identified. Continued screening of many more lines from the world germplasm collection is ongoing, as is testing of crosses of such germplasm made to advanced wheat lines. In addition to screening for WSMV resistance, research concerning TriMV will be advanced. Of major importance is the ability of the virus to infect and cause severe disease in our advanced WSMV resistance wheat lines including RonL. In addition, the virus has been identified from many locations in Kansas and thus has a wide distribution. Therefore, much emphasis is being directed towards research on this virus. The chambers have been used for this purpose. By doing so, the preliminary experiments show that only one source of WSMV temperature-sensitive resistance may be effective against TriMV.

Technology Transfer.

The technology related to use of the growth chambers is related to market improvement by developing wheat lines with resistance to WSMV and thereby reducing production losses to this constant virus threat.

Duration of Project.

The second growth chamber will be purchased upon receipt of funds within the time frame of July 1, 2007 to June 30, 2008. It is anticipated that the growth chambers will provide long-lasting tools for the research and development goals of the plant pathology and breeding programs.

Progress Report

According to the company, the Percival model PGC-15.5 growth chamber shipping date is January 18, 2008. As soon as received, installation will occur and the chamber will be used in current research and virus resistance screening work.