An integrated study of growth, enzyme activity, and water potential of wheat seeds germinated under mild water stress conditions was conducted to observe the relationship among the three kinds of parameters studied. From the relationship, the cause(s) or mechanism(s) of water stress in plant growth may be enlightened. Two important...
Four isolates of Glomus mosseae, collected from diverse
geographic locations, were pot cultured on varied host plants or
stored in the same soil as collected. Spores of three isolates failed
to germinate on any of five agar media while the fourth germinated
well on all media. Lack of germination on...
Most blackberry and raspberry (Rubus) seed exhibit delayed or poor germination because of a deep double dormancy. The objective of this study was to improve seed scarification and germination protocols for the diverse Rubus species in two subgenera often used for breeding improved cultivars. We also defined the germination potential...
Tomato is considered to be one of the most important vegetables for its value as a source
of nutrients and antioxidants, and as a model crop for biological research, including seed
biology. In this thesis, tissue-specific gene expression and its regulation in tomato seeds
were analyzed to understand the mechanisms...
Information concerning the kinds and composition of phospholipids
in gymnosperm plants is negligible in the literature. Thus this
study was undertaken to provide background knowledge for future
comparative biochemical investigations. In this study, lipid was extracted
by chloroform and methanol, and washed with distilled water
to prevent the possible formation...
The seeds of Douglas fir, a representative of the gymnosperm
flora, were studied at six stages of germination to discern the structures
of food reserves and to study ultrastructural changes occurring
during germination in the embryo and resulting seedlings.
The materials were fixed in three fixatives, dehydrated with
ethanol series,...
Published May 1975. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
The Oregon State Cooperative Seed laboratory uses two methods for testing the quality of Douglas-fir seed lots. The first of these is a straight-forward germination test without any pre-treatment of the seed, involving a period of 42 days in the germinator at alternating 20°C.-30°C. temperatures. The second method consists of...
In mature Arabidopsis seeds, the testa (seed coat) is no longer a living tissue. Thus,
major sites of gene expression in imbibed seeds are the internal living tissues such
as the embryo and the endosperm. To elucidate the molecular mechanisms of seed
germination, the gene regulation in these two tissues...
The nature of the isoprenoid pathway and diversity of biologically
significant products suggests that the pathway may be highly regulated,
particularly under stress conditions, where the availability of high
energy intermediates is limited. It was postulated that germinating
seeds suffer from a limited supply of available energy and must therefore...
Clostridium perfringens is a pathogenic anaerobic bacterium able to produce more than 17 toxins, allowing C. perfringins to cause a wide variety of diseases in humans and animals. Beside toxins production, C. perfringens able to form a highly resistance spores can survive in the environments for years. These spores are...
C. perfringens is a spore-forming, gram-positive, anaerobic pathogenic bacterium capable of causing a wide variety of diseases in both humans and animals. However, the two most common illnesses in humans are C. perfringens type A food poisoning (FP) and non-food-borne (NFB) gastrointestinal (GI) illnesses. Interestingly, these two major diseases are...
Longevity and germination of seed of western dwarfmistletoe (Arceuthobium campylopodum Engelm. f. campylopodum) of ponderosa
pine (Pinus ponderosa Laws.) was investigated to determine:
1) the influence of humidity and temperature on seed viability and
deterioration during storage; 2) the physiology of seed dormancy;
3) the composition of seed reserve food...
Germination of immature (Stage III) and mature (Stage V) wheat (Triticum aestivum L. var. Chinese Spring and Yamhill) embryos is prevented by the inclusion of 10⁻⁴ M abscisic acid (ABA) in culture medium. In addition, Stage III embryos develop into mature embryos in culture medium containing ABA. In the absence...
The enterotoxin-producing Clostridium perfringens type A isolates are responsible for the third most common foodborne illness in the United States and can also cause non-foodborne human gastrointestinal (GI) diseases such as antibiotic- associated and sporadic diarrheas. Three important factors contribute to the ability of C. perfringens to cause GI diseases,...
Clostridium perfringens is the causative agent of gas gangrene and the 3rd most common cause of type A food borne disease in the United States. Critical to the pathogenicity of C. perfringens is the ability of this bacterium to produce highly resistant, metabolically dormant spores that can resume metabolic function...
C. perfringens is a Gram-positive, spore-forming, anaerobic pathogenic
bacterium capable of causing a wide variety of diseases in both humans and animals.
However, the two most common illnesses in humans are C. perfringens type A food
poisoning (FP) and non-food-borne (NFB) gastrointestinal (GI) illnesses . These two
major diseases are...
Elite inbred sunflower (Helianthus annuus L.) lines were found to have short-lived embryo and seed covering dormancies. Seed dormancy of wild sunflowers (H. annuus, H. argophyllus and H. exilis) was found to be controlled primarily by the seed covering (seed coat and pericarp) and embryo dormancy was short-lived (four to...
Rubus seed characteristics; seed coat morphology, anatomy, germination requirements and dormancy were studied in order to define protocols for breaking seed dormancy. Morphological analysis of the seed coat (testa) using scanning electron microscopy (SEM) included 56 seed accessions of 10 subgenera preserved in the collections of the US Department of...
Clostridium perfringens is the causative agent of a wide variety of diseases in animals and humans. C. perfringens can produce more than 15 toxins. However, individual strains produce a subset of these toxins. Although a small percentage of C. perfringens isolates (mostly belonging to type A) produce C. perfringens enterotoxin...
Seed germination sensu stricto is defined as the physiological events before the radicle tip ruptures the covering tissues. The ability of the radicle to elongate (or germination potential) is observed in developing embryos prior to completion of seed maturation. When embryos at early developmental stages, such as globular, heart, torpedo...
Clostridium perfringens is a Gram-positive, anaerobic, spore-forming bacterium that can produce as many as 17 different toxins and are responsible to cause a wide array of gastrointestinal (GI) and histotoxic diseases in humans and animals. As individual strains produce a subset of these toxins, C. perfringens strains can be classified...
California brome and blue wildrye are important native grass species in the Pacific Northwest. However, both species have been reported to have low emergence under less than favorable field conditions. Seed coating is used to improve emergence and stand establishment of various crops. Three studies were carried out to determine...
A study on the effects of light quality and periodicity on the germination of Douglas-fir seed and the growth of Douglas-fir seedlings was conducted. Interest was focused on responses that could be measured and observed without biochemical assay. It was found that .Douglas-fir seed,s would respond to red-light treatments by...
Germination and survival of Douglas-fir on seedbeds of unburned,
lightly burned, and severely burned soil, charcoal, litter, and sawdust,
exposed to 100, 75, and 25 percent of full light, were studied on a
south-facing clearcutting in the Coast range of Oregon.
Irrespective of exposure to light, germination was best on...
Small broomrape (Orobanche minor) is an obligate, chlorophyll-lacking parasite that parasitizes red clover (Trifolium pratense) roots. This study was conducted to develop and implement an integrated, biologically based control program for small broomrape by using wheat as a false host to reduce the soil seed bank. The relationship between temperature...
Willamette Valley wetland prairies are some of the most endangered ecosystems in the United States, and provide habitat for many federally listed species (Wilson et al. 1993, Noss et al. 1995, USFWS 2000, Schultz et al. 2003). A rigorous program of ecosystem restoration can protect and enhance wetland plants, animals,...
The purpose of this research was to determine whether hybridization between Amelanchier denticulata. (H.B.K.) Koch and Amelanchier nervosa (Decaisne) StandL occurs in Oaxaca, Mexico, and to evaluate components of yield and germination characteristics and seed dormancy of Amelanchier denticulata. Amelanchier nervosa and Amelanchier denticulata samples and morphological characters were used...
Erigeron decumbens var. decumbens, the Willamette daisy, is known only from the Willamette Valley of Oregon. Herbarium records, from the 1800's until 1934, indicate that the Willamette daisy was once common and widely distributed throughout the Willamette Valley (Clark et al. 1993). However, between 1934 and 1980, this taxon was...
Seed size, abundance, viability, dormancy, and germination requirements strongly influence plant establishment and therefore are important considerations in restoration of native vegetation. These characteristics provide criteria for selection of suitable species, development of collection and pretreatment methods, and determination of seeding densities. The first set of objectives of this study...
Question: Most results of restoration efforts are species-specific and/or site-specific and therefore are not general enough to be easily applied to other species and other sites. Our research addresses the issue of species-specific results by investigating the feasibility of using plant traits instead of taxonomic species to characterize species responses...
Questions: Are traits related to the performance of plant species in restoration? Are the relationships between traits and performance consistent across the functional groups of annual forbs, perennial forbs, and grasses? Do the relationships between traits and performance depend on neighboring functional groups? Location: A former agricultural field, being restored...
Willamette Valley wetland and upland prairies are some of the most endangered ecosystems in the United States, and provide habitat for many federally listed species. These are dynamic systems, subject to ecological succession and invasion by aggressive non-native species, and require active management to maintain management goals. This is true...
Willamette Valley wetland and upland prairies are some of the most endangered ecosystems in the United States, and provide habitat for many federally listed species. Because these are dynamic systems, subject to ecological succession and invasion by aggressive non-native species, prairies require active management to maintain management goals. This is...
Seeding is a vital tool to facilitate recovery of degraded ecosystems, but low seedling recruitment rates limit the utility of this practice in a range of ecosystems across the globe. Plant functional traits impact individual fitness through effects on growth, reproduction and survival. Consequently, seed and seedling trait variation among...
Seashore paspalum (Paspalum vaginatum Sw.) is an important warm-season perennial turfgrass, known for its tolerance to salinity. Turfgrass is used for homes, municipalities, sod farms, resorts, and sports fields. Seashore paspalum has historically been planted in sub-tropical and tropical climates because of its heat tolerance. Seashore paspalum could become an...
Native plants provide many ecosystem services while also having great beauty and are a valuable component of the landscape. As use of these plants in habitat restoration, agricultural insectary plantings, and home landscapes increases so does demand for information on the basic biology of a group of species that have...