The Challenge: High Quality Seed of Native Plants to Ensure Successful Establishment
Kenneth P. Vogel
Native species are planted to re-vegetate former cropland, degraded pastures and rangelands, mined lands, “natural areas”, roadside right-of-ways, and other land management areas with plants, usually perennials, to stabilize and provide desirable classes of vegetation. Acceptable stands need to be obtained in a reasonable time.
Purity Testing in the Andropogoneae
Larry J. Prentice
Varying analysis reports on the same lot of seed in the chaffy rangegrasses create problems in marketing for the seed owner. Wide ranges in the percentage of pure seed for these difficult native species are reported when results are compared between laboratories and between analyses within a laboratory. This paper explains the procedures for obtaining the working sample in Andropogon gerardii, (big bluestem), Andropogon halli, (sand bluestem), Schizachyrium scoparius (little bluestem) and Sorghastrum nutans (Indiangrass).
A Philosophy of Dormancy Testing in Native Species
Native species are primarily undomesticated crops that possess high levels of seed dormancy. Seed technologists use prechill, predry, scarification, and leaching techniques during germination testing to break this dormancy. The objective of this report is to show that, while germination is increased, each of these approaches create seed stress that reduces seed viability and germination, thereby providing growers and buyers of native species incorrect information concerning the plant performance ability of the seed lot. To more accurately portray the seed quality of native species, it is proposed that a TZ test be conducted prior to the germination test to identify the viability of the seed lot followed by a germination test to determine the present performance potential of the seed lot.
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Three-Part Purity for Native Species
Sharon K Davidson
Testing of native species lends many problems to seed analysts across the United States. Besides purity and germination decisions, there is also confusion encountered when reporting seed testing results. The Rules for Testing Seeds of the Association of Official Seed Analysts (AOSA, 2000) require a four part purity analysis, incorporating Handbook 25, Uniform Classification of Weed and Crop Seeds (AOSA, 1999), for determining what is other crop or weed seed. This causes problems for the analyst and the consumer. A three part purity analysis as used by International Seed Testing Association (ISTA, 1999) combines both crop and weed seeds under one classification ‘other species’, which alleviates many of the problems encountered in reporting seed test results.Combining other crop and weed contaminates into one classification, which is represented as a single percentage, other species, on the label would harmonize seed trade around the world.
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Testing Native Species with Deep Dormancy
Nancy Vivrette* and Aleta Meyr
Testing for purity and viability of native species with deep dormancy can be difficult. A protocol is provided for obtaining a working sample, determining percent germination, determining total viability and reporting results for native species not included in the Rules for Testing Seeds (AOSA, 2001).
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Sources of Laboratory Test Result Variation in Warm-Season Grasses
T. J. Gutormson* and A. L. Patin
Variation in laboratory test results on native warm season grasses is a current issue in the seed industry. To determine if these concerns were real, samples of big bluestem (Andropogon gerardii Vitman), sand bluestem (Andropogon halli Hack), little bluestem [Schizachyrium scoparium (Michx.) Nash], Indiangrass [Sorghastrum nutans (L.) Nash], switchgrass (Panicum virgatum L.) and side oats grama [Bouteloua curtipendula (Michx.) Torr.] were tested in three seed testing laboratories. Samples for each species were split from one seed lot and mailed immediately to two of the three laboratories.
Matriconditioning Improves the Quality and Protein Level of Medium Vigor Hot Pepper Seed
S. Ilyas*, G.A.K. Sutariati, F.C. Suwarno, and Sudarsono
The objective of this study was to invigorate medium vigor hot pepper seed using matriconditioning. In one experiment, medium (80% germination, 2 year-old) vigor seeds of hot pepper were subjected to various invigoration treatments. In the subsequent experiment, medium and high (95% germination, 1 year-old) vigor hot pepper seeds were subjected to matriconditioning treatment at 15°C for 6 days using
Dimensional and Density Data and Relationships for Seeds of Agricultural Crops
Stuart O. Nelson
Dimensions of seeds of twenty different agricultural crops were determined by caliper measurements. Individual seed weights were obtained, and mean seed volumes were determined by air-comparison pycnometer measurements for use in determining seed densities. Seed densities ranged from 1.002 g/cm3 for safflower, Carthamus tinctorious L., to 1.460 g/cm3 for milled rice, Oryza sativa L. Test weight (bulk density) measurements were also taken and moisture contents were determined by standard tests.
Integrating Matriconditioning with Chemical and Biological Seed Treatments to Improve Vegetable Crop Stand Establishment and Yield under Tropical Conditions
C. Andreoli* and R. V. de Andrade
Poor stand establishment of vegetables is attributable to low seed vigor and high susceptibility to stressful biotic and abiotic soil environments. The objective of this paper was to describe the effect of matriconditioning integrated with fungicide,GA and biological seed treatments on performance of vegetable crops, and their effectiveness on physiological and biochemical changes. Matriconditioning ameliorated the performance of eggplant and tomato seeds in 1999 field plantings in Brazil. Reduction in time to 50% (T50) emergence in conditioned seeds ranged from
Germination Ecology of Two Savanna Tree Species, Tamarindus indica and Prosopis africana
Idu MacDonald*, A. C. Omonhinmin, I. A. Ogboghodo,
Various methods of seed scarification including concentrated sulphuric acid, alcohol; methanol, ethanol, iso-propanol, butanol and hot water (100°C), were applied on seeds of Tamarindus indica L. and Prosopis africana Guill and Peri., to improve germination and assess seed vigor. The highest germination and germination energy (Germ. En.) for T. indica occurred following pre-treatment in methanol for 10 minutes (70% germination; 42, Germ. En.), while better response was obtained for P. africana following pretreatment in ethanol for 10 minutes (58% germination; 38, Germ. En.), and Conc. H2SO4, for 5 minutes (60% germination; 38, Germ. En.).
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Identification of Annual and Perennial Ryegrass Using Reversed-Phase High-Performance Liquid Chromatography
Glenn W. Freeman* and Marcello J.Mangano
Reversed-Phase High-Performance Liquid Chromatography (RP-HPLC) of cereal grain proteins has received much attention in recent years as a quick and efficient means of cultivar identification. A study of perennial ryegrass (Lolium perenne L.) and annual ryegrass (Lolium multiflorum Lam.) was undertaken to determine if RP-HPLC could be adapted to the identification of these species.