| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Simplot/Jacklin Seed, West 5300 Riverbend Ave., Post Falls, ID 83854-9499
* Corresponding author (doug.brede{at}simplot.com)
‘Freedom II’ Kentucky bluegrass (Poa pratensis L.) (Reg. no. CV-77, PI 611131) is a turf-type cultivar released in July 1998 by J.R. Simplot Company, Jacklin Seed, Post Falls, ID. Freedom II was tested under the experimental designations 93-1539 and J-1539.
Freedom II was developed from an apomictic, single-plant selection from hybrid 89-1037, created in the field at Post Falls in July 1989 using ‘Midnight’ (Meyer et al., 1984) to pollinate plants of ‘Limousine’ (Alderson and Sharp, 1994). Progeny from the Limousine plants were grown in greenhouse flats during 1992 and later transferred to a spaced-plant nursery of 40701 plants. Offspring with characteristics dissimilar to Limousine were selected during maturation in the spring of 1993. Plant 93-1539 was identified as a hybrid by its leaf color and texture before seedhead expression. It averaged 33 g of seed from a single spaced plant, which is approximately double the seed production of a typical bluegrass spaced plant in northern Idaho. Seed from this plant was used to establish a turf trial in August 1993, a replicated seed yield trial in 1994, and regional trials in 1994 and 1996. Mature plants of Freedom II are most similar in appearance to Limousine, but Freedom II can be differentiated from Limousine by longer panicle length (P 
0.001) and later reproductive maturity (P 0.001). ‘Excursion’ (Brede, 2004) also originated from hybrid 89-1037. A number of other high performance Kentucky bluegrass cultivars originated from Limousine/Midnight hybridization, including ‘Absolute’, ‘Award’, ‘Awesome’, ‘Barrister’, ‘BlueMoon’, ‘Courtyard’, ‘Impact’, ‘NuGlade’, ‘Odyssey’, ‘Perfection’, ‘Quantum Leap’, and ‘Total Eclipse’ (Morris, 2002; 2003).
Progeny apomixis trials were conducted in spaced-plant nurseries near Post Falls in May 1995. A survey of 1103 plants of Freedom II showed that 8.7% of plants were variants in the vegetative (pre-heading) stage, 1.2% were heading maturity variants, 0.5% were seedhead variants, and 0.9% were miniature plants. Most variants closely resemble the majority plant form; virtually no variants express a tall, common-type appearance. The mean spaced-plant apomixis rate of Freedom II is 88%, but varies from 80 to 95% or greater, depending on growing conditions. Aberrant progeny are rogued from seedstock fields to ensure continued uniformity and stability, but they will continue to occur in every generation.
Freedom II was evaluated in the National Turfgrass Evaluation Program (NTEP) trials for Kentucky bluegrass, established in 2000 (Morris, 2002, 2003). Freedom II performed particularly well in the Great Plains states, where it was similar to the top cultivar in overall turf quality during 2001. Freedom II had dark genetic color similar to Midnight, but Freedom II had improved winter color and spring greenup compared to Midnight. Freedom II had a medium-fine leaf texture, good wear resistance, and excellent resistance to sod stretching.
Freedom II has good resistance to leaf spot [caused by Drechslera poae (Baudys) Shoem], stem rust (caused by Puccinia graminis Pers.:Pers.), and anthracnose [caused by Colletotrichum graminicola (Ces.) G.W. Wils. (teleomorph: Glomerella graminicola Politis)]. In North Carolina, it showed good resistance to dollar spot (caused by Lanzia Sacc. or Moellerodiscus Henn.).
In 7 yr of commercial seed production, Freedom II has shown the potential for high yields of quality seed, with freedom from ergot [caused by Claviceps purpurea (Fr.) Tul.] honeydew and sclerotia. Freedom II has exhibited no adverse reactions to labeled Kentucky bluegrass pesticides.
Freedom II is recommended for lawns, golf courses, parks, and sports turf in areas where Kentucky bluegrass is well adapted for turf. It can be grown in full sun or some shade. Freedom II is compatible in blends and mixtures with other cool-season turfgrasses.
Breeder seed, first harvested in 1996, is maintained by J.R. Simplot Co., Jacklin Seed. Seed propagation is limited to one generation each of Foundation, Registered, and Certified. U.S. Plant Variety Protection application no. 9900372 has been filed for Freedom II.
NOTES
Accepted for publication April 30, 2004.
REFERENCES
This article has been cited by other articles:
|
|
 |
|
  A. D. Brede Registration of 'Barrister' Kentucky Bluegrass Crop Sci., November 21, 2006; 46(6): 2718 - 2719. [Full Text] [PDF]
|
|
|
|
|
|
A. D. Brede Registration of 'Freedom III' Kentucky Bluegrass Crop Sci., November 21, 2006; 46(6): 2719 - 2720. [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| The SCI Journals | Agronomy Journal | Vadose Zone Journal | |||
| Journal of Natural Resources and Life Sciences Education |
Soil Science Society of America Journal | ||||
| Journal of Plant Registrations | Journal of Environmental Quality |
The Plant Genome | |||
