Simon: Release: MSU1558, MSU3489 |
MICHIGAN AGRICULTURAL EXPERIMENT STATION MICHIGAN STATE UNIVERSITY East Lansing, Michigan May 1, 1963 NOTICE TO SEEDSMEN REGARDING RELEASE OF CARROT INBRED LINES MSU 1558 and MSU 3489 The Department of Horticulture, Michigan Agricultural Experiment Station announces the release of two inbred carrot lines for use in production of the Fl hybrid: MSU 1558 x MSU 3489. The inbred seed parent, MSU 1558 is a male sterile of the petaloid type and both the sterile (1558S) and maintainer (1558M) will be distributed. MSU 3489 is a pollen fertile line to be used as male pa- rent in producing the Fl hybrid. The official naming and release of this Fl (MSU 1558 x MSU 3489) or others involving these lines will be delayed until foundation stocks of the inbred parents are increased. The inbred releases are made at this time to permit seedsmen to gain experience with the lines and to build up foundation stock. MSU 1558 produces a slightly tapered, stump root with a smooth dome-shaped crown. Root color is acceptable except for some green color in the core. Sol- uble solids average was 7.2% in roots grown at MSU Muck Farm. It was derived from a cross of a selected plant from Long Chantenay and a petaloid male ste- rile derived from wild carrot by Dr. H. M. Munger of Cornell University. The petaloid sterile was sent to Michigan State University by Dr. Munger in 1957 under the number, 56-11-6 x 56-36-2. The wild-carrot petaloid had been back- crossed twice to selections from domestic carrots. The original seed from Dr. Munger produced 6 petaloid steriles and 2 fertiles in the greenhouse at East Lansing. A petaloid segregate was crossed to a plant from the S2 line, MSU 1558. The sterile:fertile ratios in F1 and subsequent generations were as follows: 31:0 in Fl, 46:0 in BCl, 45:0 in BC2 and 169:0 in BC3. The BC3 in- volved a 9-plant mass under a 6' x 6' cage. The other backcrosses were to single plants. The BC3 seed, already progeny tested, is the stock being re- leased along with the S5 massed maintainer from the same cage. Additional large populations are being progeny tested in the field in Michigan and Cali- fornia. Seedsmen receiving seed will be notified immediately if fertile se- gregates appear in the field tests of 1558S. MSU 3489, also derived from Long Chantenay, produces a tapered, stump root with dome-shaped crown and exceptionally good exterior and interior color. Green pigment is absent from shoulders and core. Roots grown at MSU Muck Farm average 6.5% soluble solids. The seed being released is a mass of S3 plants selected for pollen fertility. It has been used successfully in hybrid seed production in the field and greenhouse but because of sparse pollen production, a relatively high male:female ratio may be required in hybrid production with this parent. The Fl hybrid, MSU 1558 x MSU 3489, was tested at the MSU Muck Farm in 1961 and 1962. It produces a smooth, well colored, slightly tapered stump root averaging 7.0 inches in length. It is mild flavored, both raw and processed. In a commercial processing trial preparation costs were lower then for strains of Chantenay and the product was acceptable from the standpoint of palatability. In mechanical harvesting, it was noted that there was some breaking of tops. This was not serious in the light muck soil where this trial was grown. Under |
- 2 - other conditions the weaker tops of this hybrid compared with present pro- cessing varieties may be a serious problem for mechanical harvesting. This and other characteristics of the Fl will be more fully evaluated this year. MSU 1558 and MSU 3489 are released with the following understanding: 1. These lines will not be used in commercial production of hybrid seed, other than those authorized by the releasing agency until after January 1, 1966. After that date the lines will be con- sidered fully released and available for use without further ap- proval. 2. Any hybrid named by the Michigan Agricultural Experiment Station must be sold only under that name. 3. The hybrid carrot seed producer will inform the Michigan Agriculture Experiment Station of the extent to which these inbreds are used in commercial hybrids. In complying with this stipulation the seed producer is not required to identify complete parentage of hybrids in which one of these lines in involved. 4. Any agency accepting seed under this agreement will thereby bind itself to the above stipulations. The Michigan Agricultural Ex- periment Station reserves the privilege of refusing, for an inde- finite period, additional releases to any agency failing to observe these stipulations. Seed of the pollen sterile (MSU 1558S), the maintainer (MSU 1558M) and the pollen parent (MSU 3489),produced under screen isolations in 1962, will be distributed to carrot seed producers who make a request in writing to the Department of Horticulture, Michigan State University, East Lansing, Michigan on or before May 15, 1963. _______________________ C. E. Peterson Department of Horticulture Michigan State University |