Volume 11, No. 1, 1987

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(pp. 1-6)
Methods for the Germination of Beardless Wildrye (Elymus triticoides Buckl.)1
T. J. Gutormson and L. E. Wiesner2
ABSTRACT:
A 0.2% KNO3 solution is the best moistening agent to use when viability testing beardless wildrye. Germination temperatures of 15-25 and 20 C provide equal estimations of  germination when light is used with the 20 C temperature. Beardless wildrye germination was equal in light and dark environments when using the 15-25 C temperature.

Prechilling prior to germination extends the testing period and does not improve germination percentages. Beardless wildrye germination at 15-25 or 20 C in a light environment with 0.2% KNOs for 35 days provides the best viability estimate of all germination methods evaluated. A 35-day germination test may not be practical. Germination for 21 days followed by tetrazolium evaluation of remaining seeds is recommended.
Additional Index Words: KNO3, temperatures, prechill.
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(pp. 7-14)
Determining Seed Quality of Winterfat [Ceratoides lanata (Pursh.) J. T. Howell]1
Phil S. Allen, Susan E. Meyer, Tim D. Davis2
ABSTRACT:
Studies with seeds of winterfat [Ceratoides lanata (Pursh) J. T. Howell] were conducted  preparatory to submitting a proposal for an addition to Rules For Testing Seeds. "Threshed seeds", "fruits ≥  3 mm in length," and "'all winterfat fruits': were evaluated as criteria for determining what should be considered pure seed in laboratory testing.

Seed analysts are advised to follow existing guidelines and classify dt winterfat fruits, regardless of size, as pure seed. The minimum weight for purity analysis is 12 grams. Evaluation of laboratory germination methods showed "in covered petri dishes on the surface of moistened blotters" to be a suitable substratum, and 15o C. constant temperature for 14 days without light is recommended for laboratory germination. For fresh lots, prechilling at 5°C for 14 days is recommended.
Additional index words: germination, seed testing, wildland seed.
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(pp. 15-22)
Changes in Lipid Fatty Acids Associated With Dormancy Breaking in Amaranthus albus Seeds1
R. Chadoeuf-Hannel and R. B. Taylorson2
ABSTRACT:
Changes in lipid fatty acids associated with the breaking of dormancy by phytochrome in Amaranthus albus L. seeds were investigated. Changes in polar lipids occurred within 4 hours after dormancy was overcome by a stimulatory red irradiation. In irradiated seeds, the percentage of unsaturation in polar lipid increased as shown by enhanced linoleic acid content. In seeds maintained in dormancy, the polar lipid fatty acid composition also changed but opposite to that observed in irradiated seeds. The results suggest the involvement of membrane lipids in the transition from a dormant to a non-dormant state in seeds.
Additional Index Words: Membrane, phytochrome, polar and nonpolar lipids, red irradiation, temperature.
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(pp. 23-34)
Relationship of Germination and Vigor Tests to Field Emergence of Snap Beans (Phaseolus vulgaris L.)1
C. Samimy,  A. G. Taylor, and T. J. Kenny2
ABSTRACT:
Four laboratory tests were evaluated for their ability to predict the potential field emergence of snap beans (Phaseolus vulgaris L.). Standard germination, accelerated aging, cold soil test and conductivity test were conducted on commercial seed lots and the results were correlated with seedling emergence in two field plantings in 1982 and 1983.

Cold test showed the highest significant correlation with all four field plantings followed by the conductivity tests. The accelerated aging and the germination test results correlated with the field emergence of the first planting in 1983. However, when the field emergence from 1982 and 1983 was combined and averaged across the two planting dates the accelerated aging test correlated with the field emergence.
In a separate study conducted in 1983, seeds of 'Flo' were artificially aged for 0, 1, 2, 3 and 4 days. The values of cold and conductivity tests followed by the germination test were highly correlated with the field emergence.
Additional index words: accelerated aging, cold test, conductivity, seed quality, seed vigor, stand establishment.
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(pp. 35-41)
Pictures and Descriptions of Certain Apiaceae (Umbelliferae) Fruit Not Illustrated in U.S. Department of Agriculture handbook No. 301
Deborah J. Lionakis Meyer2
ABSTRACT:
Descriptions and drawings of fruit structures of the Apiaceae (Umbelliferae) not illustrated in Agriculture Handbook No. 30 are provided for three taxa: Anthriscus caucalis Bieb., Torilis amensis (Huds.) Link subsp. arvensis and T. arvensis (Huds.) Link subsp. purpurea (Ten.) Hayek.

Additional drawings are included of the polymorphic fruit of Torilis nodosa (L.) Gaertner. Nomenclatural corrections are provided for six taxa in this family which are illustrated in Agriculture Handbook No. 30 (U.S. Department of Agriculture 1952).
Additional Index Words: schizocarp, mericarp, cremocarp.
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(pp. 42-51)
Seed Pellets for Improved Seed Distribution of Small Seeded Forage Crops1
Albert E. Smith and Richard Miller
ABSTRACT:
Broadcast seeding of forage crops having small seed is difficult and often results in uneven stands due to the inability to consistently meter seed flow. Broadcast seeding of forage species into areas where ground equipment cannot operate is being accomplished with aircraft. The small light seed of forage grass and legume species cannot be uniformly broadcast from an aircraft due to wind currents and packing of the seed in the aircraft container. The purpose of our research was to develop seed-pelleting methods for bermudagrass [Cynodon dactylon (L.) Pers.] and ladino clover (Trifolium repens L.) with improved metering and ballistic properties for increased precision and accuracy of seed distribution from aerial seeding.

Seed pellets developed with kaolin clay and several binders were tested for pellet strength and destructability and seedling establishment in  greenhouse pats, Pellets made from formulations containing polyvinyl alcohol binder  resulted in strong pellets that had a low percentage of destruction when tumbled for one hour. These pellets resulted in excellent seed germination (>85%) and seedling establishment for both ladino clover and bermudagrass. The pellets could be stored for up to 6 months while maintaining good seed viability and Rhizobium trifolii viability. The seed can be accurately distributed at low rates from an aircraft equipped with a Meterater™ applicator (Elanco Products Co., Indianapolis, IN). Pellets sprayed with diammonium phosphate (dap) produced the best bermudagrass seedling establishment. The dap, when  sprayed on Iadino clover seed pellets, damaged the clover seedlings. The use of pelleted seed should increase precision and accuracy of seed distribution from an aircraft and should allow for the use of lower seeding rates.
Additional index words: Polyvinyl alcohol, kaolin clay, legumes, grasses, aerial seeding, broadcast seeding.
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(pp. 52-61)
Evaluation of the Dot-Immunobinding Assay for Detecting Phytopathogenic Bacteria in Wheat Seeds1
L. E. Claflin and B. A. Ramundo
ABSTRACT:
A dot-immunobinding assay (DIA) was evaluated for detecting Pseudomonas syringae pv. syringae, P. s. pv. atrofaciens, Clavibacter tritici, and Xanthomonas campestris pv.  translucens in wheat seeds.

Crossreactions between antigens and antisera of P. s. pv. syringae and P. s. pv. atrofaciens negated the use of DIA in distinguishing these incitants. X. c. pv. translucens provided positive readings only when cell concentrations were 105 colony forming units (CFU/ml) or higher. tritici cells were also detectable at 105 CFU/ml. The DIA was most valuable in identifying X. c. pv. translucens colonies after the seed leachate was plated on semi-selective media. The assay was not reliable for detecting low cell numbers directly from seed. Cell concentrations of X. c. pv. translucens declined only about 10-fold in wheat seeds after three years of storage.
Additional Index Words: Basal glume rot, black chaff, spike blight, bacterial leaf blight.
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(pp. 62-68)
A Field Study of Moisture Content of Soybean Pods and Seeds After Harvest Maturity1
R. W. Yaklich and P. B. Cregan2
ABSTRACT:
Field weathering of soybean, [Glycine max (L.) Merr.], seeds, after harvest maturity, reduces seed germination and increases disease incidence. Therefore, the objective of this paper was to determine if there were genotypic differences in pod and seed moisture of three Maturity Group III and Maturity Group IV cultivars.

Two replicates of each cultivar were grown to harvest maturity in 1979 and 1980. Twenty pods were collected from each plot at 800 and 1300 h daily, shelled, and pod and seed weight determined gravimetrically. Dry weight of pods and seeds was determined after 24 h at 100o C.
Moisture content of soybean pods and seeds fluctuated daily. Moisture content of pods and seeds of Group III cultivars was significantly higher at the 800 h sampling time than at the 1300 h. Significant differences between pod moisture content of Group III cultivars were observed in 1979, which was a wet harvest season. These results agree with previous laboratory observations and suggest that there is genotypic variability in pod moisture uptake.
Additional index words: Glycine max (L.) Merr., Field weathering, Dew, Precipitation.
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(pp. 69-78)
Seed Treatment in Rice
V. Krishnasamy and D. V. Seshu1
ABSTRACT:
Rice (Oryza sativa Linn.) seeds are treated prior to storage with insecticides and fungicides to ward off the external agents of seed damage. Fumigation controls the insects that have already infested the seeds. Several pre-sowing seed treatments are available to prevent seedling mortality during germination. Such treatments not only enhance seedling establishment but also the crop performance. A few areas of rice seed treatment requiring further studies are also indicated.
Additional index words: Storage, pesticide, fumigation, pre-sowing.
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(pp. 79-87)
Interfacing the ASAC-1000 Seed Analyzer with an IBM-PC Microcomputer Using the Basic Program ASACSTAT1
K. C. Furman, L. W. Woodstock, and T. Solomos2
ABSTRACT:
The ability to obtain seed quality population statistics from seed steep water conductivity measurements based on large sample sizes could lead to standardized conductivity indices for vigor and viability for a greater number of seed kinds. The ASAC-100 seed analyzer3 simultaneously measures the steep water conductivity of 100 individual seeds. By directly interfacing the ASAC-1000 with an IBM-PC computer using the BASIC program ASACSTAT, various analyses or experiments can be designed and large quantities of data collected for statistical analysis.

In addition, ASACSTAT permits the ASAC-1000 to take readings automatically at predetermined intervals, allows a tray to be divided into any number of sections, gives a compressed printout and is easy to operate. The low cost of microcomputers makes such an analysis system affordable for seed testing laboratories and research institutions.
Additional index words: computer, vigor, seed quality, deterioration, aging, seed, seed testing, leachate, conductivity.
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(pp. 88-96)
Peanut Seed Production1
Gary A. Reusche2
ABSTRACT:
A brief overview of topics relating to peanut seed production and testing based on selected research and extension publications is presented.3 Topics relating to seed production include the morphology of the peanut plant and seed, field isolation requirements, seed calcium requirements, harvest management and conditioning.

Seed testing issues include inter-laboratory variability in germination testing, the development of procedures for a seedling vigor classification and a 3-hour dynamic conductivity analysis, a variant on the standard seed seeds are low in vigor, and the relationship between vigor and the seedbed environment.
Additional Index Words: Arachis hypogaea. Seed Harvest, Seed Conditioning,
Seed Processing, Seed Testing, Seed Vigor.
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(pp. 97-102)
The Influence of Soaking Pepper Seed in Water or Potassium Salt Solutions on Germination at Three Temperatures1
Kenneth W. Jones and D. C. Sanders2
ABSTRACT:
Pepper (Capsicum annuum L.) seeds were soaked in water, a 1% KNO3 + 1% K2HPO4 solution, or a 1.5% KNO3 + 1.5% K2HPO4 solution at 21°C for either 72 hrs or 96 hrs. Seeds were air dried and germinated at 15oC, 20°C, or 25°C. All soaking treatments hastened germination and resulted in more uniform germination.

The velocity of germination was increased by soaking treatments and this increase was promoted by greater germination temperatures. Seed soaking reduced germination index more at 15°C than 20°C or 25°C. Soaking seed in water or a 1% KNO3 + 1% K2HPO4 solution gave similar results and were slightly better in promoting germination than the 1.5% KNO3 + 1.5% K2HPO4 solution.
Additional index words: seed treatment, seed invigoration, Capsicum annuum L.
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