MICHIGAN AGRICULTURAL EXPERIMENT STATION MICHICAN STATE UNIVERSITY East Lansing, Mich.
June 3, 1968
NOTICE TO HYBRID CARROT SEED PRODUCERS REGARDING RELEASE OF CARROT INBRED LINE MSU 5931, MSU 6000 AND THE HYBRID SPARTANSWEET (MSU 5931 x MSU 6000)
The Department of Horticulture, Michigan Agricultural Fxperiment Station announces the release of two inbred carrot lines for the production of the F1 market-type hybrid SPARTANSWEET (MSU 5931 x MSU 6000).
The seed-parent inbred, MSU 5931, is a male-sterile of the petaloid type developed with the original wild-carrot cytoplasm first described and provided for our program by Dr. Henry Munger of Cornell University. Both the sterile (MSU 5931S) and its maintainer (MSU 5931M) will be distributed. This line was derived from the open-pollinated variety, Imperator. It has been progeny tested through five successive backcross generations without producing fertile rogues.
The pollen parent was derived from the variety Empress inbred to S2 then mass selected for three generations. Both lines are relatively free from green shoulder and green or yellow core. The F1 approximates the variety Imperator in length and type. It is recommended for trial as a fresh market carrot or for processing as a sliced carrot in areas where Imperator is acceptable.
SPARTANSWEET has been tested at the Michigan State University Muck Experi- mental Farm for three years where it produced yields comparable to Imperator and was judged to be superior to Imperator in flavor and both exterior and interior color. It was widely distributed for experimental trials in 1967 and received favorable coment from widely scattered producing areas. In 1968, extensive commercial trials are being conducted by Dr. Clark Nicklow with fresh-market carrot producers in Michigan.
MSU 5931 and MSU 6000 are released with the following understanding:
1. These lines are considered fully released and may be used by seedsmen for development of hybrid combinations with lines of their own origin or from other sources. The combination MSU 5931 x MSU 6000 will be sold or otherwise distributed only under the name SPARTANSWEET.
2. The hybrid carrot seed producer will inform the Michigan Agricultural Experiment Station of the extent to which these inbreds are used in commercial hybrids.
3. Since these inbred lines have shown some promise as open-pollinated varieties the Michigan Agricultural Experiment Station reserves the right to name and release either or both as commercial varieties.
4. Any seed producer accepting seed under this agreement will thereby bind itself to the above stipulations. The Michigan Agricultural Experiment Station reserves the privilege of refusing, for an in- definite period, additional releases to seedsmen failing to observe these stipulations.
Seed of the inbred lines grown under greenhouse or screen isolation will be distributed to prime producers of carrot seed who make a request in writing to the Dept. of Horticulture, Michigan State University, East Lansing, on or before June 17 1968. ________________________________ C.E. Peterson