Volume 9, No. 2, 1984

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(pp. 99-113)
Effect of Planting Equipment and Techniques on Seed Germination and Emergence: A Review
Michael D. Orzolek and Donald R. Daum1
Vegetable production has changed in the last 300 years because of improvements in the quality (germination and vigor) of seeds. When seeds are placed in the hostile environment of the soil, as short an interval from planting to emergence is essential to reduce the stresses placed on the seed from temperature, moisture, microorganisms and pesticides.

In the production of transplants, seed germination and especially vigor are also important for subsequent uniform and vigorous growth in the field. New planting equipment and techniques have been developed which are more efficient and/or precise requiring less labor for both vegetable transplanting and seed sowing. Modern planters have evolved which place seeds at a uniform depth and coverage without appreciable  seed damage. Planters now employ belts, discs, vacuum, and cups as mechanisms for depositing seeds from the planter box to the soil furrow. The gel seeding ( fluid drilling ) technique offers many options for increasing seed germination, uniform emergence and  higher yields. Continued research related to stand establishment will insure future  improvements in the establishment and yield of vegetables.
Additional index words: Fluid drilling, direct seeding, transplants, seed vigor, soil crusting.
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(pp. 114-136)
QSeed: Computer Assisted Management for the Seedsman1
G. A. Reusche, R. D. Keys and R. L. Angle, Jr.2
QSeed (Quality Seed) is a set of BASIC language programs designed to keep records on seed production, conditioning, testing, inventory control and sales. These records are then accessed for management and quality assurance operations. Crops and varieties being produced are defined, as well as addresses of growers and buyers.

One program keeps records on production fields, inspections, yields and related items. At harvest QSeed maintains records on each bulk storage bin, the removal of seed from the bin, conditioning information including the assignment of lot numbers, and the location of lots in bagged storage. QSeed follows the flow of the seed and develops an inventory, seed testing and quality assurance file for each lot. If more than one seed analysis has been made, the results of all seed testing information can be displayed in the form of a histogram. When a sale is made QSeed first displays lot records on the screen and then allows selection of a specific lot. When the selection is made, an invoice is printed, along with a load-out ticket and the adjustment of the bagged seed inventory. QSeed runs on many brands of microcomputers using the PC/MS DOS operating system.
Additional index words: Agricultural software, seed software, seed computer, seed conditioning, seed inventory, seed microcomputer, seed warehousing.
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(pp. 137-149)
Separation of Annual and Perennial Species of Ryegrass by Gel Electrophoresis of Seed Proteins1
J. M. Ferguson and D. F. Grabe2
Rapid and effective techniques that would complement the seedling fluorescence test are needed to differentiate annual (Lolium multiflorum Lam. ) from perennial ( L. perenne L. ) ryegrass. Electrophoresis procedures have been successful in separating the two species, but differences between them are often based only on band intensity. The purpose of this work was to develop an electrophoretic procedure that would, by presence or absence of distinct bands, differentiate between annual and perennial ryegrass, detect mixtures of the two species, and possibly detect ploidy level of annual ryegrass.

Proteins were analyzed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis ( SDS-PAGE ) . Seventeen annual, three intermediate (L. hybridum Hausslen), and 14 perennial cultivars were tested. The annual and intermediate cultivars possessed characteristic protein bands at Rf 0.71 and 0.73 that were not found in any of the perennial cultivars. Moreover, bands were present in the perennial cultivars at Rf 0.80 and 0.88 that were absent or very faintly stained in the annual and intermediate cultivars. The banding patterns for annual and intermediate species were similar.
To test for contamination of perennial ryegrass seed lots with small percentages of annual ryegrass seed, mixtures of annual and perennial ryegrass seed were made in  concentrations of 0, 1, 3, 5, 10, 25, 50, 75, and 100% annual seed. Annual bands were visible in the samples containing 25% or more annual seed. Densitometer scans could detect the annual bands in the mixtures containing 10% annual seed, but lower percentages of annual seed could not be detected in the bulk seed mixtures. Protein extracts of individual seeds were electrophoresed to determine whether species mixtures can be detected on an individual seed basis. When individual seeds were used, the resulting banding patterns were different than those produced from bulk seed extracts from the same cultivar. Furthermore, no two seeds within a cultivar showed the same banding patterns. However, the characteristic annual bands at Rf 0.71 and 0.73 were still evident in most single seeds from annuals. Likewise, the characteristic perennial bands at Rf 0.80 and 0.88 were normally present in individual seeds of the perennials. Individual seeds could be identified by either or both pairs of these bands or bands in other zones.
The SDS-PAGE procedures used in this study were successful in differentiating between annual and perennial ryegrass. Bulk seeds and single seeds of the two species show distinct species-specific banding patterns. Perennial ryegrass seed lots contaminated with 10% or more annual ryegrass seed could be detected by analyzing bulk seed. No characteristic banding patterns were detected that would allow determination of ploidy level among annual ryegrass cultivars.
Additional index words: Lolium multiflorum Lam., L. perenne L., L. hybridum Hausslen, SDS-PAGE, varietal determination.
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(pp. 150-161)
Electrophoretic Patterns of Storage Proteins in Phaseolus Prone to Cotyledonal Cracking1
Zahra N. Hashim and William F. Campbell2
Cotyledonal- or transverse-cracking (TVC) in certain cultivars of snapbean, Phaseolus vulgaris L., seeds, clearly evident during germination, places affected seedlings at a competitive disadvantage. TVC is an inherited trait and occurs across cell walls of cotyledons rather than along the cell walls. This study examines the hypothesis that TVC results from the swelling of storage proteins in seeds during imbibition.

One hundred seeds were selected randomly from each of 17 seed lots. Each bulk sample weighed 225 g; 15 cultivars were represented. Separated proteins were subjected to electrophoresis under denaturing and nondenaturing conditions, and the molecular weights of the different protein bands were determined. Differences in patterns of polyacrylamide gel electrophoretograms of proteins from resistant and susceptible cultivars are reported. Different protein banding patterns were identified and correlations with the TVC  phenomenon were attempted. There were visual differences between banding patterns of resistant and susceptible cultivars, although it is not clear which protein bands are associated with the TVC phenomenon. The technique requires further refinement before plant breeders can use it to screen for TVC-resistant snapbean cultivars.
Additional Index Words: Transverse cracking, snapbeans, electrophoresis, SDS-PAGE, sodium dodecyl sulfate, polyacrylamide gel.
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