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 STRATIBERRY BREEDING

 C. II. Howard
 Associate Professor (Plant Pathologist)

 Objectives: To develop new strawberry varieties that are specifically adapted to
 Florida growing conditions.

 Table 1. Numbers of seedling clones tested in 1972-73, 1973-74 and 1974-75 seasons.

 No. clones No. selected No. of clones
 Season fruited for observation in rep. trial

 1972-73 2,339 134 18
 1973-74 2,596 181 16
 1974-75 1,956 12


 First year (Field 5): Crosses are made in the greenhouse during the winter and
 seeds are sown in flats in late March or early April. Seedlings are transplanted
 into individual peat pots in Hfay or early June and set in the nursery in late June
 where they form runners. In October, clones are selected from the nursery on the
 basis of runner production and resistance to anthracnose, leaf spot and leaf blight.
 Four plants of each selection are transplanted into the fruiting field where rec-
 ords are kept on fruit yield and other characteristics. Specific clones are se-
 lected primarily on the basis of early (through Jan.) and total (through Harch)
 yields, and fruit color, size, appearance and ripening characteristics. Some clones
 are selected for specific characteristics such as long fruit stems or concentrated
 ripening in an effort to develop lines that may be useful for mechanical harvesting.

 Second year (Field 6): The clones that have been selected are transplanted into
 the summer nursery where they are again observed for runner production and resis-
 tance to anthracnose. In October, selections are made from this group and trans-
 planted into 10-plant observation plots. Two plantings of most of these are made
 two weeks apart to obtain some information on the best date of planting for each
 clone. In this trial the clones are compared with currently grown varieties and
 the fruit and plants are observed more closely for any defects such as poor color
 or soft fruit. Specific clones are selected on the basis of plant type, early and
 total fruit yield, and fruit firmness, color, size, ripening characteristics and
 general appearance. These clones are transplanted into the nursery in April where
 they are again observed for runner production and resistance to diseases (especially
 anthracnose).

 Third year (Field 2): The most promising clones from the second year observational
 trials are placed in replicated trials where they can be thoroughly compared with
 varieties currently being grown in Florida. After a clone has shown sufficient
 promise at least two years in replicated trials, a variety release committee may
 be formed. If the committee, after reviewing all the accumulated data, agrees
 that the specific clone should be an improvement over currently grown varieties,
 then it can be named and released as a new variety. Hopefully, more extensive
 grower testing of varietal candidates will be done in the future even though
manpower and time limitations make it very difficult for us to grow the large
numbers of plants that are required for these tests.