Volume 10, No. 1, 1986

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(pp. 1-23)
Ancient Seeds; Seed Longevity
Vivian K. Toole1
ABSTRACT:
This paper tells about the widespread publicity, following archaeological excavations, given to "mummy" grain and its viability, identification of ancient grain as to species, findings of wild species, species grown in ancient times and conclusive evidence that mummy grain is nonviable. A brief reference is made to the longevity of the lotus seeds  from Pulantien and to herbarium and buried seeds, and to present knowledge of seed viability under controlled conditions, to imbibition, dormancy and hard-seed effects on longevity and a glimpse into Alladin's lamp of seed immortality.
Additional index words: buried seeds, mummified seeds, viability.
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(pp. 24-36)
Variety Testing by Official AOSA Seed Laboratories1
R. C. Payne2
ABSTRACT:
A questionnaire concerning variety testing was sent to 66 official AOSA seed testing laboratories. Forty-four of the responding seed laboratories routinely test vegetable and/or agricultural seeds and 86 percent of these laboratories engage in variety testing. The variety testing procedures most widely used by AOSA member laboratories are

evaluations of morphological seed characteristics and certain "quick" chemical tests. More AOSA seed laboratories conduct variety tests on samples of wheat, barley, oat, soybean, cowpea, sorghum, and Kentucky bluegrass than on samples of other kinds.
Additional index words: Variety testing, morphological seed characteristics, "quick" tests, growth chamber, electrophoresis, field tests.
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(pp. 37-45)
Optimizing Time of Harvest for Seed of Allium cepa L.1
C. A. Neal and L. A. Ellerbrock2
ABSTRACT:
Six time-of-harvest trials were conducted over a 3-year period to define the optimum time at which the seed crop of onion (Allium cepa L.) should be harvested. Individual plots were harvested over a 7- to 16-day period beginning when the first capsules dehisced. Yield increased as either a linear or quadratic function of time.

Percent shattering umbels increased nearly logarithmically over time, whereas average individual seed weight increased linearly. Actual losses due to shattering were inconsequential until 25% or more of the umbels were losing seed. Growers were harvesting 2 to 5 days earlier than optimum. There was no advantage to selectively harvesting shattering umbels, compared to a once-over harvest at 25-30% shattering. Seed quality was not significantly affected by harvest date.
Additional index words: onions, seed production.
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(pp. 46-57)
Positioning AOSA for the Future1
Dennis M. TeKrony2
ABSTRACT:
An anniversary is an excellent time to inventory previous accomplishments and to plan for the future. The other speakers in this symposium have provided an overview of the goals, accomplishments and shortcomings of their respective societies for the past 75 years. It is my intent to examine the present status of the Association of Official Seed Analysts (AOSA) and to position this association for the future.

To accomplish this I plan to (1) re-examine the objectives of AOSA and discuss their application to seed testing in the 80's, 90's and the year 2000, (2) provide short term recommendations for improving seed testing within the next 10 years, ( 3 ) take a look ahead over the next 25 years and ( 4 ) submit a proposal for seed research in the future.
Additional index words: Research, goals, objectives.
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(pp. 58-61)
Effect of Stratification, Drying, and Cold Storage on Noble Fir and Pacific Silver Fir
Oscar Hall and Ed Olson1
ABSTRACT:
Four stored lots of noble fir, Abies procera Rehd. and two of pacific silver fir, A. amabilis (Dougl.) Forbes, were soaked in tap water for 48 hours at room temperature, stratified for 28 days at 4oC., dried to a moisture content between 5 and 9%, followed by 14 cold storage treatments.

Both species were held in cold storage up to 360 days after drying without any significant loss in viability. All storage periods resulted in improved germination over the controls, which were germinated immediately after stratification without redrying. The combined effect of all lengths of cold storage on germination was not consistent between species and seed lots.
Additional index words: Abies procera Rehd., Abies amabilis (Dougl.) Forbes, germination, viability, prechill.
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(pp. 62-67)
A Method for Quantifying Color of Phenol Reaction on Wheat Seed1
K. M. Steen, O. L. Karsky, and J. D. Maguire2
ABSTRACT:
The similarity in seeds of wheat (Triticum aestivum L. ) cultivars makes identification by morphological characteristics difficult. The phenol test is used to identify cultivars and to determine cultivar mixtures and mixtures of winter and spring types. The various colorations in the seed coat caused by the phenol oxidation make identification possible. The Munsell Soil Color Charts were used as reference in identification of color of 37 various cultivars. Evaluation by phenol testing requires known samples and careful timing to assure accurate evaluation.
Additional index words: cultivar identification, variety identification, phenol reaction, Munsell soil color chart.
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(pp. 68-73)
Assessment of a Simple Mechanical Shaker for Measuring Screening in Barley
D. J. Martin1, B. T. McLean1, and R. J. Mayer2
ABSTRACT:
A simple, mechanically operated shaker, suitable for routine testing of samples from barley breeding programmes, was used to determine the effect of shaking time on 'screenings' produced from two contrasting barley samples. The shaker was fitted with a single screen with 2.2 mm apertures. Screenings increased asymptotically as shaking time was extended, a minimum of 5 min being needed to give a constant screenings figure. With 5 min shaking, the means and 95% confidence intervals for the varieties Clipper and Pirouette were 8.1 ± 0.5 and 15.7 ± 1.2 respectively.
Additional index words: barley quality, grain size, grain assortment.
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(pp. 74-80)
Magnetic Conditioning of Seeds of Leek (Allium porrum L.) to Increase Seed Lot Germination Percentage1
P. Krishnan and A. G. Berlage2
ABSTRACT:
Magnetic conditioning of seed lots involves treating either with iron powder and moisture or with magnetic fluid. The treated mixture is passed over a magnetic drum separator. Effects of these conditioning methods in improving germination percentages of leek seeds were investigated.

Low- and high-grade commercial leek seed lots cleaned in a commercial plant were used. Treatments included iron powder/moisture or magnetic fluid at two different dilutions-7:1 and 4:1. A commercial, permanent magnetic drum separator, measuring 0.08 tesla magnetic flux density at its surface, was used to separate the magnetics from the nonmagnetics. Both magnetic and nonmagnetic fractions were weighed and seed counts were taken. Germination tests were carried out on all fractions. The 7:1 diluted magnetic fluid and the iron powder/moisture conditioning methods were effective in removing low-germinating seeds to meet acceptable marketing standards. The 4:1 diluted magnetic fluid was effective in removing low-germinating seeds, but produced excessive crop seed loss. Magnetic conditioning methods to improve germination were effective for high-grade leek seed lots but not for low-grade leek seed lots.
Additional index words: Magnetic-fluid, iron-powder.
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