Download or read book A Comparison of Plant Characteristics of Annual Ryegrass Oregon Lolium Multiflorum Lam and Linn Perennial Ryegrass Lolium Perenne L written by C. H. Rosell and published by . This book was released on 1967 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt: Studies were conducted to establish some characters which could be used, either in the field or in the laboratory, to differentiate between annual ryegrass (Oregon), Lolium multiflorum Lam., and Linn perennial ryegrass, Lolium perenne L. Vernation, percentage of glumes covering the spikelets, and height of seedlings seem to be fully reliable characters to differentiate the plants under study. Texture of the tillers, blade width, spikes length, spikelets length, glume length, callus shape of the rachilla, and rachilla length, seem to be relatively good characters for differentiating these species. Number of tillers, embracement of the auricles, number of spikelets per spike, teeth on the lemma, awns on the lemma, and weight of the seedlings are inadequate characters to differentiate between the species studied. Leaf color might be a useful guide to detect contamination, when the species are grown under identical conditions.

Download or read book The Ryegrasses written by Harry August Schoth and published by . This book was released on 1940 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Turfgrass Bibliography from 1672 to 1972 written by James B Beard and published by . This book was released on 1977 with total page 744 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Annual Ryegrass Lolium Multiflorum Lam written by and published by . This book was released on 1999 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Annual Ryegrass Lolium Multiflorum Lam written by D. B. Hannaway and published by . This book was released on 1998 with total page 2 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ecology Production and Management of Lolium for Forage in the USA written by Francis Marion Rouquette and published by American Society of Civil Engineers. This book was released on 1997 with total page 164 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Management and Uses of Annual Ryegrass lolium Multiflorum in California written by United States. Soil Conservation Service and published by . This book was released on 1973 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Measurement of Outcrossing in Lolium Spp as Determined by Fluorescence Tests written by Lawrence O. Copeland and published by . This book was released on 1968 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt: Research was conducted to determine the distance and amount of outcrossing between varieties of highly fluorescent annual ryegrass (Lolium multiflorum Lam.) and low-fluorescing perennial ryegrass (Lolium perenne L.). Studies were conducted under both spaced-plant and seed production field conditions. Fluorescence tests on seed collected from low-fluorescing perennial ryegrass at successive distances from the fluorescent annual ryegrass pollen source revealed that outcrossing was considerably less than that reflected by present certification isolation distances. Outcrossing under spaced plant situations decreased rapidly and became minimal at a distance of 100 feet. Crossing between adjacent high-density fields was substantially below that revealed between space-planted ryegrass. Under field conditions, outcrossing became negligible after about ten feet, and no evidence of crossing was observed at distances greater than 40 feet.

Download or read book Performance of Perennial Ryegrass Lolium Perenne L Seed Crops Under Water Stress Conditions written by Theodosius Marmaduke Velloza and published by . This book was released on 1997 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: Summer drought is a major factor limiting the regrowth of perennial ryegrass seed crops. This phase of crop development has a strong influence on seed yield because most of the tillers that contribute towards next season's seed crop are produced or regrown during this period. In recent years many seed fields have exhibited premature decline probably because of extensive drought after harvesting. Therefore, this study was undertaken to (i) assess how post-harvest leaf and tiller development is impacted by the timing and severity of water stress and (ii) identify potential relationships of water stress to flowering and seed yield. Rain-out shelters were used to exclude rainfall from two cultivars which received either no irrigation or 2.5 cm of simulated rainfall in mid-August or mid-September or both. These were compared to an ambient treatment. No rainfall decreased total tiller production by approximately 30% in 1995 and 50% in 1996. There were also moderate reductions in tiller dry weight, tiller height, and slight decreases in number of leaves and the basal diameters. The trend showed that the cultivar Affinity responded quicker to an early irrigation whereas the cultivar Buccaneer had a longer period of summer dormancy. Total soluble sugars concentrations increased as tiller number decreased suggesting the potential for rapid compensatory growth upon alleviation of drought. Limited irrigation during the post-harvest period of regrowth did not generally affect fertile tiller number nor seed yields. Fewer vegetative tillers as the stands aged, together with other changes in plant parameters, may mark the beginning of the dieback problem. In greenhouse studies, four cultivars were rapidly stressed using vermiculite as a growth medium. Though little differences were observed among cultivars when physiological responses were evaluated, stomata' diffusive resistance and leaf temperatures increased, whereas plant water potential and leaf transpiration decreased as stress was prolonged. Plant survival following water stress was largely dependent on cultivar and gravimetric water content of vermiculite. This technique did not reasonably simulate natural drought conditions in terms of plant physiological performances nor soil characteristics, but it was useful to differentiate the ability of different genotypes to survive a drought-induced dieback.

Download or read book Perennial Ryegrass Lolium Perenne L Cultivar Response to a Postemergence Application of Mesotrione written by Barbara J. Hinds-Cook and published by . This book was released on 2017 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: Perennial ryegrass (Lolium perenne L.) is a widely grown cool season, bunch type, short lived perennial grass that is native to Europe, Asia, and North Africa, but has been adapted globally. Perennial ryegrass is quick to establish, has a long growing season, and produces high seed yield and forage or turf quality (high density, fine leaves, and dark green color). Mesotrione is a selective 4-hydroxyphyenyl pyruvate dioxygenase (HPPD) inhibiting herbicide used for weed control in perennial ryegrass seed production and turfgrass in the USA. HPPD inhibiting herbicides cause a reduction in carotenoids which protect chlorophyll from high energy light. The photodegradation of chlorophyll results in a bleaching of leaf tissue in susceptible plants. In seed production, mesotrione, commercialized in the USA as Callisto®, is applied postemergence in the spring to fall planted perennial ryegrass seed crops. Mesotrione for use in turfgrass, commercialized in the USA as Tenacity®, is applied pre or postemergence. The effects of a postemergence application of mesotrione on chlorophyll concentration, dry biomass, plant height, and seed yield and germination compared to an application of another HPPD inhibitor, pyrasulfotole-bromoxynil, on perennial ryegrass cultivars were evaluated. There were differences in perennial ryegrass cultivar response to a postemergence application of both HPPD inhibitors in chlorophyll concentration and to a postemergence application of pyrasulfotole-bromoxynil in dry biomass. No reduction in plant height was caused by the HPPD inhibitors. Seed yield of the perennial ryegrass cultivars was not negatively impacted by a postemergence application of mesotrione. However, only twelve perennial ryegrass cultivars were evaluated in this study; therefore, caution may be warranted when using mesotrione with other perennial ryegrass cultivars. The effects of mesotrione applied postemergence on perennial ryegrass cultivars at three different temperatures, 5, 25, and 35°C, on chlorophyll concentration, leaf color, and total chlorophyll were investigated. At each temperature, there was a response within some cultivars. The cultivar ‘Derby Xtreme’ exhibited the most sensitivity to mesotrione at 5°C and ‘SR 4660ST’ was the most sensitive at 35C. The cultivar ‘PR 8821’ was the most sensitive overall at all evaluation timings and temperatures. The cultivar exhibiting the most tolerance to mesotrione was ‘Esquire’. Assessing perennial ryegrass cultivar response to mesotrione at one temperature versus another temperature resulted in ‘Allstar 3’ exhibiting less sensitivity at 35 than at 5 or 25°C. The majority of cultivars exhibited more sensitivity at 25 than at either 5 or 35°C. Turfgrass managers should use caution when applying mesotrione postemergence to some perennial ryegrass cultivars if temporary bleaching of the turf is undesirable.

Download or read book Identification of Species and Varieties of Ryegrass Lolium Spp written by Manoel Bernardo De Barros and published by . This book was released on 1974 with total page 91 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this study was to investigate ryegrass seedling characteristics that, by themselves, or combined with presently known characters, could improve varietal identification tests. Thirteen characters were studied on 30 varieties of Lolium multiflorum Lam., L. perenne L., L. rigidum Gaud, and L. hybridum Hausskn., including leaf size and area, epidermal characteristics, structural elements, and leaf blade vernation. Mean differences among species occurred in the following characteristics: Lolium multiflorum. and L. perenne: leaf width, leaf length, leaf area, minor and major vascular bundles, lower and upper sclerenchyma fiber groups, hair density, number of vascular bundles, and leaf blade vernation, Lolium multiflorum and L. hybridum; leaf width, leaf length, leaf area and leaf vernation. Lolium perenne and L. hybridum: leaf width, leaf length, leaf area, and total of sclerenchyma fiber groups, and leaf vernation. Lolium perenne and L. rigidum: leaf width, leaf length, leaf area, and leaf vernation. Lolium multiflorum and L. rigidum: leaf blade vernation. Lolium hybridum and L. rigidum: leaf blade vernation. Tetraploids and diploids were significantly different on the average, within their respective species, as follows: Lolium multiflorum: leaf width, leaf length, leaf area, stomata density. Lolium perenne: leaf width, leaf length, leaf area, stomata density. Lolium hybridum: stomata density, and number of major vascular bundles. Some significant differences among varieties within species and ploidy levels were observed in the following characteristics: Lolium multiflorum tetraploids: leaf width, leaf length, leaf area, minor vascular bundles. Lolium multiflorum diploids: leaf width, leaf length, leaf area, minor vascular bundles, total vascular bundles. Lolium perenne tetraploids: leaf area. Lolium perenne diploids: leaf length, leaf area, minor vascular bundles. Although varietal means differed for many of the characters, individual plants could not be identified on the basis of a single character. An illustration was prepared to show how a combination of morphological characters might be used in varietal identification. With a table of varietal means for nine characters, only two (Jolanda and Tetrone--both tetraploids of L. multiflorum) of the 30 varieties studied were indistinguishable. The leaf blade vernation of Wimmera (L. rigidum) and. Tetrelite (L. hybridum) appeared to be intermediate between that of L. multiflorum and L. perenne. The vernation was folded from the midrib, like in L. perenne, while the edges of the leaf were inrolled and overlapping, somewhat like L. multiflorum. This type of vernation is being called semi-rolled, to conveniently distinguish from "rolled" and "folded."

Download or read book Experiments on the Genetics and Cytology of Perennial Rye grass Lolium Perenne L and Italian Rye grass L Multiflorum Lam written by L. Corkill and published by . This book was released on 1933 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Seed Yield and Yield Components of Pennfine Perennial Ryegrass Lolium Perenne L as Influenced by Time and Rate of Spring Nitrogen and Chemical Dwarfing written by William Clyde Young and published by . This book was released on 1987 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seed yield in perennial ryegrass is the product of yield components that develop during the life of the plant. Crop yield potential is defined by the number of fertile tillers, spikelets per spike, and florets per spikelet. It has been shown that perennial ryegrass realizes only a small percentage of the potential as harvested seed, and is an inherently poor seed producer as cultivars have been selected primarily for vegetative production or desirable turf characteristics. The Willamette Valley of Oregon produces nearly all of the perennial ryegrass seed grown in the United States. Environmental conditions during plant growth control potential yield development and the efficiency with which it is used. To increase the efficiency of seed production, it is important to understand the effects specialized cultural management techniques have in this producing region. In these studies on perennial ryegrass, the effects of varying the amount and time of spring applied nitrogen (N), and the effects of the plant growth retardant paclobutrazol were investigated under field conditions using the cultivar Pennfine. In addition, the influence of high levels of early spring N, combined with growth retardant use was investigated. Increased tiller densities, the result of higher N level, can result in a greater seed yield potential. However, as tiller densities become greater, the components of seed yield on individual tillers become smaller. In addition, earlier and more severe lodging result in greater tiller mortality and harvest dry weight losses. Split spring applications totaling 120 to 150 kg N ha−1 appeared to provide a better balance between compensating yield components, while maintaining an economic seed yield. Spring application of paclobutrazol delayed the onset and severity of lodging, resulting in an increased number of fertile tillers in the stand, and a greater number of potential seed sites per unit area. Earlier dates of application had a greater effect in reducing lodging in 1983, but no difference was observed between two spring growth stages in 1984. Reduced lodging appears to enhance seed set, resulting in a greater number of seeds recovered at harvest and a higher floret site utilization (FSU). Harvest index was also increased with paclobutrazol. Application of paclobutrazol significantly increased seed yield, a result of improved seed recovery due to more seeds per spike. However, the increased yield potential resulting from higher N rate was not recovered by application of paclobutrazol where severe lodging conditions occurred prior to the completion of seed filling. Under more normal environmental conditions, 120 kg N ha−1, followed with a growth retardant application, had a significantly greater seed yield than the other treatments.

Download or read book Segmental Morphology of Perennial Ryegrass Lolium Perenne L written by Arif Hasan Khan Robin and published by . This book was released on 2011 with total page 604 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Competitiveness of Perennial Ryegrass Lolium Perenne L and Its Ability to Withstand the Invasion of Annual Bluegrass Poa Annua L microform written by Daniels, Robert Wesley and published by Ann Arbor, Mich. : University Microfilms International. This book was released on 1989 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Multiple resistant Italian Ryegrass Lolium Perenne Spp Multiflorum Populations in Oregon written by Mingyang Liu and published by . This book was released on 2013 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt: Italian ryegrass (Lolium perenne spp. multiflorum) is a common weed management problem in turfgrasses, cereals and non-crop areas in the United States. In Oregon, the number of populations with multiple-resistance continues to increase. To manage these resistant populations, the resistance patterns must be determined. In this study, five Italian ryegrass populations (CT, R1, R2, R3 and R4) from two cropping systems were studied for resistance patterns and mechanisms. The CT population is from a Christmas tree plantation and was resistant to at least six herbicides with four different mechanisms of action: atrazine, diuron (2.4-fold), glyphosate (7.4-fold), hexazinone (3.1-fold), imazapyr (1.8-fold), and sulfometuron. The resistant indices (RI) for sulfometuron and atrazine could not be calculated because 50% growth reduction for the CT population was not reached even with the highest rates applied, 17.6 kg ai ha−1and 16 kg ai ha−1, respectively, which are 16 times the recommended field application rates for this two herbicides. The CT population accumulated less shikimate than the S population. There were two mutations in the CT population, Trp591 to Leu in the ALS gene and Ser264 to Gly in the psbA gene, which explain the ALS and PII cross resistance, respectively. R1, R2, R3 and R4 were collected from annual cropping systems. All four populations were resistant to flufenacet. RIs for two populations, R2 and R4, were 8.4 and 5.9, respectively. R2 and R4 also were resistant to mesosulfuron-methyl, pinoxaden, quizalofop and clethodim. R4 was resistant to diuron, but R2 was not. An Asp-2078-Gly substitution in the ACCase gene was found in both R2 and R4 populations, while another Ile-2041-Asn substitution in the ACCase gene was found in the R4 population. These mutations explain the ACCase cross resistance in the R2 and R4 populations. The mechanisms for the glyphosate resistance in the CT population and the flufenacet resistance in R1, R2, R3 and R4 populations were not identified in this study. None of the five populations were resistant to the herbicide pyroxasulfone.

Download or read book Agrobacterium mediated Transformation of Perennial Ryegrass Lolium Perenne L for Cold Tolerance written by Carmille Joanna C. Bales and published by . This book was released on 2010 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: