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New Developments in Tall Fescues and Use Strategies. Leah A. Brilman, Ph.D. Research Director Seed Research of Oregon. The Breeding Process. 1. Establish a goal 2. Identify breeding material 3. Cross selected parent plants (clones) 4. Progeny Trials 5. Verification Trials
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Leah A. Brilman, Ph.D.Research DirectorSeed Research of Oregon
The Breeding Process • 1. Establish a goal • 2. Identify breeding material • 3. Cross selected parent plants (clones) • 4. Progeny Trials • 5. Verification Trials • 6. Varietal increase
Goals for Tall Fescues • Improved brown patch resistance • Rhizomes for recovery • Improved establishment • Drought avoidance and recovery • Improved root growth • Maintenance of turf density • Improved recovery • Traffic tolerance and recovery • Reduced elongation and mowing • Good aesthetics - Dark color, fine textured
Tall Fescue for Sports • Why use tall fescues for sports turf? • Wear tolerant once established • Drought tolerant - non-irrigated sites • Survives low maintenance • Problems for sports turf • Recovery from wear slow • Reestablishment slow • Less thatch or cushion • Determining best other species for blends • Best varieties for sports may not be available
Identify BreedingMaterial • Existing varieties or breeding populations • Survivors in trials with high stress • Collections • Old cemetaries, parks, sports fields • Related Species • Genetic Engineering-Biotechnology
Identify Breeding Material • Screen for disease resistance - brown patch • resistance in Missouri
Identify Breeding Material • Survivors in trials with high stress
Identify Breeding Material • Survivors in trials with high stress - acid soil/drought stress in Georgia
Cross Selected Parent Plants (Clones) • Small to medium block of plants • (from 2 (common in Europe) to over a hundred) • The progeny or offspring that are grown • from the seed are called half-sibs
Progeny Trials (Repeated 2 to ? times) • Select superior progeny • Root evaluations • Spaced plants • Turf plots • Evaluated usually from 2 to 4 years • Evaluate progeny for production • Seed Yield, Disease resistance • Repeat the cycle
Progeny Trials • Root evaluations
Goals for Tall Fescues • Improved brown patch resistance • No complete genetic resistance found • Incidence related to nitrogen, leaf wetness, nightime temperatures • Leaf wetness related to turf density • Many strains of brown patch - poor correlation in resistance across sites • Wider leaves - less disease • Selection - reduced density, semi-dwarfs • Genetic engineering, Hybrids?
Brown Patch Screening • Plant clonal nursery of tiller plants • Mow, fertilize, innoculate w/ multiple strains • Select best plants and clone into another location • Best plants crossed with each other and susceptible plants • Identify inheritance and genetics - may be possible to find genes for resistance • Can look at other turf traits at same time
Goals for Tall Fescues • Rhizomes for recovery • Primary observation on spaced plants - not in dense sod • Kentucky bluegrasses vary in rhizome expression in dense sod • Bluegrasses develop rhizomes at 28 days • Red fescues develop rhizomes much later • Tall fescues in greenhouse have few rhizomes at 70 days, significant at 7 months
Goals for Tall Fescues • Rhizomes for recovery • Longest rhizomes in Mediterranean germplasm but turf quality not high • Rhizomes occur primarily in open areas • Other turf qualities must be considered - • density, diseases resistance • Tall fescues need time before wear applied • Combine with transitional ryegrass, bluegrass for sports turf
Goals for Tall Fescues • Improved establishment • Faster establishment • Establishment under lower soil temperatures • Multiple cycles of selection • Still influenced by production dormancy • Less dormancy when seed produced in moist environment • Dormancy broken by winter storage • Need germination and rapid growth - same varieties may not be NTEP winners
Goals for Tall Fescues • Grub Resistance • Current endophytes do not have enough alkaloids in root system to help • Grub resistance important for drought tolerance • Some endophytes increase root growth enough to help • Screen for drought resistance then insert beneficial endophytes
Verification Trials • 1. Turf Trials • NTEP - Ancillary Trials • Additional trials - unique characteristic • 2. PVP trials • Establish unique variety • Morphological traits • Physiological traits • Disease resistance
Find location and management • Closest to site • Same management • Similar environment with same management • Specialized trials - traffic or sod strength • Traffic trials - need ones that emulate sport and location • Fall/spring wear, summer wear, winter-active growth
NTEP data • Usually on permanent turf • Not at seeding rates commonly used • Management often different than user • Usually without traffic or with artificial traffic • Need traffic sooner with higher seeding rates • Color often overides other important • characters
Genetic studies • Tall fescue is hexaploid - more difficult to study • One set of chromosomes from meadow fescue = perennial ryegrass • Noble Foundation - Expressed Sequence Tags • Identify genes differentially expressed in drought or heat stressed plants • Develop markers from these tags • Apply marker assisted selection
Genetic Modification • Primary targets to date have been forage targets • Reduced lignin content - may improve mowing but would not improve wear tolerance • Successful in tissue culture and transformation • Maybe useful in brown patch resistance if correct gene could be found
Future Work • Evaluation for traffic resistance • Need traffic with drought • Continued selection of tall fescues under • drought and disease stress • Identification of other selection techniques • Trials with other species