Volume 3, No. 2, 1978

Download Cover and Index

Download AOSA-SCST Cultivar Verification Symposium (free download)

(pp. 1-11)
Relationship Between Seed Vigor and the Storability of Soybean Seed1
D. B. Egli, G. M. White, and D. M. TeKrony2
Soybean (GIycine max (L.) Merrill) wed must be stored and the quality maintained from harvest in the fall until planting time in the spring. These studies were conducted to  evaluate the relationship between laboratory tests of vigor and the storage potential of soybean seed.

Three seed lots of each of 4 cultivars ('Williams', 'Cutler 71 ', 'Dare', and 'York') were selected to provide lots that were high in viability as measured by standard germination but had a range in vigor as measured by the accelerated aging germination test. All seed lots were stored at 10.5 and 13.5 9% moisture content (MC) in controlled environment chambers. The temperature in the chambers was adjusted to follow the average temperature from November 1 to August 1 for the central U.S. Samples were  collected for viability and vigor determinations after 1, 4, 6 and 9 months in storage.
The initial standard germination of all lots except one was above 85 % while the initial accelerated aging germination ranged from 33.5 to 95 %. The initial rate of germination (4-day count) was closely  related to the standard germination but averaged 5 percentage  points lower. The accelerated aging test was most sensitive to deterioration during storage followed by the rate of germination and the standard germination was the Feast sensitive. The accelerated aging test was an excellent predictor of storability and the relationship between the initial accelerated aging germination and deterioration during storage was similar for all cultivars.
Additional index words: Glycine max L. Merrill, standard germination, rate of germination (4-day count), accelerated aging germination.
Download entire article

(pp. 12-22)
The Effects of Alternaria brassicicola Infection on Brassica Seed Vigor and Viability1
E. M. Chirco and G. E. Harman2
A thiram seed soak reduced, but did not eliminate, Alternaria brassicicola (Schw.) Wilt. infection and damping-off symptoms from infected Brassica seed lots. It did not improve germination in blotter tests or field emergence but both the thiram and water soak treatments accelerated emergence under controlled conditions and in the field.

The weight per seed was reduced in seeds produced on plants inoculated with A. brassicicola at either petal fall or midpod stages. No seeds from plants inoculated at petal fall germinated in either laboratory or field tests. Regardless of the stage of development when plants were inoculated, laboratory and field germination was reduced. Seeds from ripe pods showed no difference in emergence under optimal germina­tion conditions in the laboratory in field soil, whether sprayed with water or inoculated with A. brassicicola. These data indicate that seed infection at any stage of seed development causes a reduction in seed quality. Effective con­trol measures should be developed for the seed crop since eradicative seed treatments are ineffective in restoring loss of seed vigor and viability caused by A. brassicicola.
Additional index words: seedborne diseases
Download entire article

(pp. 23-29)
Use of Length-Width Measurements and Seed Characteristics to Distinguish Cultivars of Poa pratensis L., Kentucky Bluegrass1
E. F. Wiseman and T. Koszykowski2
The continuing introduction of new cultivars of Kentucky bluegrass in the seed market has required new studies to identify seeds of these cultivars through dimensional and topographical characteristics. Length and width measurements, seed characteristics, and drawings are used to describe 21 cultivars in addition to those described in earlier work by Wiseman (3) and Niemyski and Grzelak (1).

Additional index words: Kentucky bluegrass, cultivars, seed character­istics.
Download entire article

(pp. 30-40)
An Evaluation of Alternative Methods of Accelerated Aging Seed Vigor Test for Soybeans1
Kar-Ling J. Tao2
Two alternative accelerated aging vigor test methods for soybeans were evaluated, namely the large chamber method and the sealed jar method.

With the large chamber method, a significant variation in the final seed moisture content, fungal growth, and percent of high vigor seedlings oc­curred among samples from the same seed lot, depending on their location in the accelerated aging chamber. This variation among samples did not occur when the accelerated aging test was conducted by the sealed jar method. However, seeds with higher initial moisture contents deteriorated more rapidly than seeds with lower moisture content. Placing multi-samples in one jar in order to save accelerated aging chamber space, resulted in a variation among samples. The height of the seed sample above the water affected the test results; the higher the sample the higher the percent of high vigor seedlings. The use of a square plastic germination box instead of a jar could save accelerated aging chamber space.  The optimum amount of water for the plastic box was determined to be 40 ml.
Additional index words: Glycine max (L.) Merr., germination.
Download entire article