Commercial pre-emergence trials

 Several harvester-unit block trials have been established with
cooperators to evaluate pre-emergence herbicides in sweet corn under field
conditions. Randox and Simazine appear to be superior chemicals in trials
which will be harvested in May.

Miscellaneous experiments

 Response of celery to gibberelic acid

 In a replicated trial gibberelic acid was applied to 52-70 celery
at 0, 10, 20, and 40 ppm at three weeks before normal harvest. The treated and
check plants did not differ in number or length of petioles or in yield of fresh
trimmed plants. Bitterness, fibrousness, flavor and toughness of inner and
outer petioles and preference were evaluated by a panel led by Dr. C. Hall of
the Department of Food Technology and Nutrition at Gainesville. None of these
quality measures was influenced favorably by gibberelic acid treatment and the
check plants were preferred by the panel.

 Gibberelic acid was applied to 259-19 celery in non-replicated
demonstration plots. Neither plant measurement, yield nor quality were influenced
favorably by the treatment.

 Response of seed potatoes to gibberelic acid slurry treatment

 Potassium gibberelate (K GA) slurry treatment was applied to
 dormant Red Pontiac whole and split seed potatoes at three rates: none,
 recommended (2 oz. of 0.88% K GA per 100 pounds of seed), and twice the
 manufacturer's recommended rate (4 oz.). Sprout emergence at three weeks
 after planting was increased by seed treatment. Many sprouts were markedly
 etiolated and spindly, especially at the higher rate. At six weeks after
 planting, stand in split-seed plots was not increased by treatment while
 stand in whole-seed plots was increased by K GA. Plants from treated seed
 pieces had poorer foliage with small leaves and developed sparse, spindly
 and prostrate vines. Yield of tubers greater than 2" in diameter was highest
 from non-treated seed. Total yield from whole tubers was increased slightly
 by K GA, but total yield from untreated split-seed was more than tw
 from K GA treated seed pieces. Tubers were saved from the main crop; held
 at 40 F for several months; and then field planted. Emergence and stand
 did not differ among plots from check and treated seed.

 Current seed dip treatments in gibberelic acid solutions should not
 be supplanted by slurry treatments without establishment of more appropriate
 dosages. Gibberelic acid is not registered for use on vegetables.

 Space seeding of celery with seed sheets

 Several techniques for space planting of celery seed in plant
 beds have been evaluated. Current research involves controlled random distri-
 bution of seed affixed to sheets of soluble fibers. Plantbed populations of
 about 60 seedlings per square foot have been grown from seed sheets. The
 seedlings have been vigorous and uniform; most plants were taken in one pulling.

 EES 60-18
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