many other characteristics such as color, date of seedhead appearance and height to make a uniform variety.
Kentucky bluegrass is the exception due to its apomictic reproduction. It is hard to get hybrids, with often only 10% of plants in
a cross being the hybrids, the rest being genetically identical to the
mother plant. These hybrids usually have all the chromosomes of
the mother plant and about half of the father. Each plant is a shot
in the dark but if you do get a good plant that is apomictic the
progeny will all be the same and it can be a new variety.
The general outline for breeding is
1. Establish a goal (Improved wear tolerance, diseases resistance)
2. Decide how to screen for improvements ( Select in turf trials
or spaced plants)
3. Screen a large number of plants and select the best ones
4. Cross these plants together letting wind scatter the pollen
(small crossing cages or bigger blocks of related plants), harvest
seed, plant new trials
5. Evaluate progeny for selected improvement (perhaps select
best plants again)
6. Seed from best plants or lines bulked together as Breeder
Seed
7. Breeder Seed used to plant first seedstock field and enter
into NTEP and other trials
8. Seedstock (Foundation) seed used to plant Certified fields
Improvement of turfgrass varieties is dependent on being able to
efficiently screen large numbers of plants for the desired characteristic(s). The selected plants need to be crossed together and the progeny (offspring) evaluated again for the characteristic(s). If the
characteristic is highly heritable the majority of the population may
then have the characteristic or additional cycles of selection must be
performed. Due to the complex inheritance of many desired characteristics being able to concentrate many of them in one population or
variety is often difficult. It is often necessary to evaluate the selected
plants and progeny over a number of years and environments to reliably screen for some characteristics. Screening for wear tolerance was
BREEDER BLOCK OF TALL FESCUE. Seed from the isolated plants
are planted in the greenhouse and spaced plants are established into a
Breeder block (each row has plants derived from one plant). Look for uniformity and seed yield or these progeny. Usually also planted in turf
plots. Poor performers will have the whole row eliminated.
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