Download or read book Temperature and Moisture Effects on Stand Establishment of Seven Winter Wheat Cultivars and Selected Progeny Triticum Aestivum L Em Thell written by Michael Patrick Conway and published by . This book was released on 1977 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: Laboratory studies were conducted under different temperature and moisture regimes to evaluate the effects of temperature and moisture on stand establishment and seedling characteristics associated with stand establishment. Percent stand and days to 25% emergence were used as indexes of stand establishment. Seedling characteristics analyzed were: shoot length, coleoptile length, seedling dry weight, and Adenosine Triphosphate (ATP) content. Each of these characteristics were tested with regards to predicting stand establishment over a wide range of temperature and moisture conditions. Experiments on stand establishment were also conducted under field conditions at the Sherman Experiment Station in north-central Oregon. The degree of association between stand establishment estimates obtained in the field and estimates of stand establishments obtained in the laboratory was determined. Attempts were also made to determine the mode of inheritance of coleoptile length and Adenosine Triphosphate and the association of these characteristics with stand establishment in early generations. Seven soft white winter wheat cultivars (Yamhill, Moro, Stephens, McDermid, Hyslop, Luke, and Daws) were used in the laboratory and field experiments. Parents, F1 s, and F2s from crosses among four of the cultivars (Yamhill, Moro, McDermid, and Daws) were utilized in the inheritance studies of coleoptile length and ATP. Broad sense heritability estimates for coleoptile length were computed using the parental and F2 variances. Frequency distribution of coleoptile length were tested for their fit to normality by use of the chi square test. Narrow sense heritability estimates for coleoptile length and Adenosine Triphosphate were computed using the standard unit (correlation) and regression methods. Three temperatures levels 8, 15, and 22°C) and three soil moisture levels ( -2, -4, and -6 bars) were used to study the effects of temperature and moisture on stand establishment and stand establishment characteristics of the seven cultivars in the laboratory. Different temperature and moisture levels exhibited significant effects on percent stand, days to 25% emergence, shoot length, coleoptile length, seedling dry weight, and ATP. Increasing temperature from 8 to 22°C resulted in decreases in percent stand, days to 25% emergence, and coleoptile length. Shoot length, seedling dry weight, and ATP increased as temperature was increased from 8 to 22°C. Increasing moisture stress from -2 to -6 bars had a significant negative effect on percent stand, emergence rate, and each of the seedling characteristics studied. Coleoptile length was found to be the best predictor of percent stand over the entire range of temperature and moisture combinations utilized in the laboratory. Percent stand was observed to decrease whenever coleoptile length was less than the depth of planting. Shoot length was found to be the best predictor of days to 25% emergence over the entire range of temperature and moisture levels. Semi-dwarf cultivars produced poorer stands than tall cultivars due to their coleoptile length. This difference in stand establishment capability was most pronounced under the warmest temperature (22°C) and the greatest moisture stress ( -6 bars). Estimates of minimum gene number together with data obtained from frequency distribution indicated that the inheritance of coleoptile length was controlled by one to three major genes and possibly some modifier genes. The close agreement between broad and narrow sense heritability estimates indicated that the expression of coleoptile length is controlled primarily by additive gene action. This suggests that selection for coleoptile length in early generations should give reliable estimates of coleoptile length expression in later generations. The heritability of Adenosine Triphosphate (ATP) was found to be subject to cytoplasmic influence. Maternal effects in the F1 generation, the occurrence of considerable inbreeding depression in the F2 generation, and relatively low narrow sense heritability estimates suggest that ATP can not be used as a selection character for seedling vigor in early generations of wheat in a conventional breeding program. Several characteristics (coleoptile length, ATP, plant height, and seed weight) were tested for their association with percent stand in the F 1 and F2 populations. None of these characteristics were significantly correlated with percent stand. Of these characteristics, coleoptile length produced the highest correlations with percent stand in the F 1 and F2 generations. The use of coleoptile length as a selection character for percent stand in early generations appears promising.

Download or read book Factors Associated with Stand Establishment and Subsequent Grain Yield of Seven Wheat Cultivars and Selected Progeny Triticum Aestivum L Em Thell when Grown Under Three Diverse Environments written by Mohammad Ali Vahabian and published by . This book was released on 1976 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Physiology and Biochemistry of Seed Development Dormancy and Germination written by Anwar Ahmad Khan and published by . This book was released on 1982 with total page 566 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seed development and germination; Phenotypic maternal effect of photoperiod on seed germination; Seed dormancy and germination; Seed vigor, stress and seed germination.

Download or read book O S U Theses and Dissertations 1978 1982 written by Oregon State University and published by . This book was released on 1983 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Agronomy News written by and published by . This book was released on 1978 with total page 712 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sept.-Oct. issue includes list of theses and dissertations for U.S. and Canadian graduate degrees granted in crop science, soil science, and agronomic science during the previous academic year.

Download or read book Comprehensive Dissertation Index Agriculture written by and published by . This book was released on 1984 with total page 1080 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Agriculture Agronomy written by University Microfilms International and published by . This book was released on 1977 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Comprehensive Dissertation Index written by and published by . This book was released on 1984 with total page 1086 pages. Available in PDF, EPUB and Kindle. Book excerpt: Vols. for 1973- include the following subject areas: Biological sciences, Agriculture, Chemistry, Environmental sciences, Health sciences, Engineering, Mathematics and statistics, Earth sciences, Physics, Education, Psychology, Sociology, Anthropology, History, Law & political science, Business & economics, Geography & regional planning, Language & literature, Fine arts, Library & information science, Mass communications, Music, Philosophy and Religion.

Download or read book Effect of Soil Temperature Seeding Date and Straw Mulch on Plant Development and Grain Yield of Two Winter Wheat and Two Winter Barley Cultivars written by Alpaslan Pehlivantürk and published by . This book was released on 1975 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two winter wheat (Triticum aestivum L. em Thell) and two winter barley (Hordeum vulgare L. em Thell) cultivars were grown with and without straw mulch utilizing six different planting dates. Soil temperature was recorded continuously at seeding depth from planting date through March of the crop year. A series of thermocouples connected to a point recorder were used for the soil temperature measurements. Soil temperature data were condensed through the use of a computer to obtain monthly averages for fallow treatments (bare and straw mulch) and diurnal variations. Plant growth in terms of days to emergence and days to tillering was noted for each planting date and related to the average soil temperature. Soil temperature differences between the bare and mulch (2400 kg/ha wheat straw) fallow treatments were small. Slightly higher soil temperatures were recorded in the mulched plots but the differences had no significant effects on emergence and tillering. Average soil temperatures decreased gradually at each subjecent planting date but differences in the time interval between planting, emergence and tillering for the first four dates were slight. When considering the first four dates of planting the time interval between planting and emergence ranged from 9 to 11 days, while between emergence to tillering time interval ranged from 17 to 29 days. For the fifth and sixth planting date the interval between planting and emergence and emergence and tillering increased sharply ranging between 14 and 20 days and 51 and 125 days, respectively. These increases in time intervals between plant growth stages corresponded with relatively rapid decreases in average soil temperatures during the same period. Significantly lower grain yields were observed for the early (14 August) and late (1 November) planting dates when compared to the other four planting dates. The early planting date produced excessive vegetative growth and many tillers early in the season and may have used much of the stored moisture in the soil in the fall. There was also severe lodging in these plots. The first two planting dates also showed heavy infestation of barley yellow dwarf virus. The plants from the late planting lacked sufficient growth to efficiently use the moisture that was available. Within the second to fifth planting dates all four cultivars exhibited a differential response in yield and for some agronomic traits indicating distinctly different types of adaptation. Higher yields were noted for the barley cultivars, Hudson and Schuyler, at the second and third planting dates while the yield levels of the wheat cultivars, McDermid and Moro, were higher at the fourth and fifth planting dates. Differential responses in plants per square meter and tillers per plant at the same planting dates showed opposite trends, e., as the former increased the latter decreased. Neither of these two traits appeared to contribute to grain yield. The fallow treatments, bare and straw mulch had no significant effect on grain yield in the cultivars studied. However, a significantly higher 1000 kernel weight was observed with the straw mulch treatment. Number of plants per square meter was significantly higher under bare fallow than under mulch fallow treatment. All cultivars showed differential response to fallow systems in tillers per plant but not in yield and other agronomic traits. McDermid and Hudson responded to the mulch fallow while Moro had good response to the bare fallow in tillers per plant. Schuyler responded almost the same to the both mulch and bare systems in tillers per plant.

Download or read book American Doctoral Dissertations written by and published by . This book was released on 1976 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Influence of Drought on Stand Establishment of Winter Wheat Cultivars written by R. H. Skinner and published by . This book was released on 1983 with total page 51 pages. Available in PDF, EPUB and Kindle. Book excerpt: Five varieties and three breeding lines of winter wheat (Triticum aestivum L.) were compared for drought resistance at the seedling stage. Emergence under a greenhouse line-source sprinkler system was compared with germination in PEG 6000 and mannitol solutions as well as with seed weight and the ability to emerge from deep planting. No significant correlation existed between line-source emergence and germination in PGE or mannitol, emergence from deep planting or seed weight. Within varieties, light seeds (average 50 seed weight 1.313 g) germinated better under moisture stress than heavier ones (average 50 seed weight = 1.991 g) but there was no significant correlation between seed weight and germination among varieties. Seedling maturation rates were measured using the Haun index while total dry weight was used to indicate productivity. Shoot weight, root weight, root/shoot ratio, leaf water potencial and plant height were compared with productivity and maturation rate. None were found to be correlated with the index. Plant height, shoot weight and root weight were all significantly correlated with total dry weight. Plant height is suggested as a convenient, nondestructive indicator of total plant productivity. No correlation was found to exist between emergence under drought conditions and the ability of seedlings to grow under moisture stress. What little relationship existed between the two was generally negative, making incorporation of drought resistance at both stages into one variety difficult.

Download or read book Effect of Soil Moisture Temperature Bulk Density and Texture on Emergence of Three Wheat Varieties Triticum Aestivum L written by Mahmut Basri Halitligil and published by . This book was released on 1975 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effects of soil moisture ( -2 to -17 bars), temperature (5 to 20°C), bulk density (0.90 to 1.40 gm/cm3) and texture (Bashaw silty clay and Woodburn silt loam) on germination and seedling emergence of three varieties (Yamhill, Bezostaya, Kirac 66) of wheat (Triticum Aestivum, L.) were evaluated under laboratory and field conditions. Experiments include: 1) germination of three wheat varieties in osmotic solutions made from Carbowax 6000 to evaluate the effect of osmotic potential and temperature oi germination, 2) measurement of seedling emergence for three wheat varieties in Bashaw and Woodburn soils as influenced by soil water potential and temperature, 3) measurement of seedling emergence for the three varieties at three planting dates to test the applicability of the laboratory response to field conditions, and 4) measurement of seedling emergence of Kirac 66 as affected by bulk density and soil water potential in Bashaw and Woodburn soils. The effect of seed protein content on germination and emergence was evaluated by using high and low protein samples (16.50 and 7.75 percent, respectively) of Yamhill wheat in the first three experiments. The number of days required to obtain 50 and 80 percent germination in osmotic solutions and seedling emergence in soil was significantly increased by lowering either temperature or water potential. Although significant interactions were measured, temperature affected germination more than water potential. There was a significant difference in the germination and emergence times of Yamhill, Bezostaya and Kirac 66. Kirac 66 emerged the fastest while Bezostaya consistantly emerged the slowest. Seed protein did not affect germination or seedling emergence of Yamhill variety. Models were developed using linear regression analysis for the laboratory seedling emergence study to predict the number of days required to obtain 50 and 80 percent emergence in Woodburn soil and 50 percent in Bashaw soil as a function of soil water potential and soil temperature. Since the response to the variables were similar, the models were composite for the three varieties. The models were used to determine soil water potential and temperature combinations which permit emergence to occur within a specified time. Soil texture and bulk density significantly affected the time required for seedling emergence. More days were required to obtain seedling emergence in Bashaw silty clay than in Woodburn silt loam soil at given soil water potential primarily because of less seedsoil contact. Emergence was delayed by bulk densities greater than 1.20 and 0.90 gm/cm3 in Woodburn and Bashaw soils, respectively, because of increased soil strength. Data collected from three seeding dates made in the field in general confirmed the findings in the laboratory concerning the effects of soil moisture and temperature. Bezostaya emerged the slowest while Yamhill emerged the fastest. Seed protein content did not affect emergence. Applicability of the laboratory models to field conditions could not be established because of insufficient data.

Download or read book Annual Meetings Abstracts written by American Society of Agronomy and published by . This book was released on 2000 with total page 518 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bibliography of Agriculture written by and published by . This book was released on 1991 with total page 510 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bibliography of Agriculture with Subject Index written by and published by . This book was released on 1991 with total page 530 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Handbook of Official Grain Standards of the United States written by United States. Agricultural Marketing Service. Grain Division and published by . This book was released on 1949 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Crop Stress and its Management Perspectives and Strategies written by B. Venkateswarlu and published by Springer Science & Business Media. This book was released on 2011-11-22 with total page 617 pages. Available in PDF, EPUB and Kindle. Book excerpt: Crops experience an assortment of environmental stresses which include abiotic viz., drought, water logging, salinity, extremes of temperature, high variability in radiation, subtle but perceptible changes in atmospheric gases and biotic viz., insects, birds, other pests, weeds, pathogens (viruses and other microbes). The ability to tolerate or adapt and overwinter by effectively countering these stresses is a very multifaceted phenomenon. In addition, the inability to do so which renders the crops susceptible is again the result of various exogenous and endogenous interactions in the ecosystem. Both biotic and abiotic stresses occur at various stages of plant development and frequently more than one stress concurrently affects the crop. Stresses result in both universal and definite effects on plant growth and development. One of the imposing tasks for the crop researchers globally is to distinguish and to diminish effects of these stress factors on the performance of crop plants, especially with respect to yield and quality of harvested products. This is of special significance in view of the impending climate change, with complex consequences for economically profitable and ecologically and environmentally sound global agriculture. The challenge at the hands of the crop scientist in such a scenario is to promote a competitive and multifunctional agriculture, leading to the production of highly nourishing, healthy and secure food and animal feed as well as raw materials for a wide variety of industrial applications. In order to successfully meet this challenge researchers have to understand the various aspects of these stresses in view of the current development from molecules to ecosystems. The book will focus on broad research areas in relation to these stresses which are in the forefront in contemporary crop stress research.