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Book Genetic Variation in Douglas fir

Download or read book Genetic Variation in Douglas fir written by David F. Van Haverbeke and published by . This book was released on 1987 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Genetic Variation of Douglas fir in the Northern Rocky Mountains

Download or read book Genetic Variation of Douglas fir in the Northern Rocky Mountains written by G. E. Rehfeldt and published by . This book was released on 1974 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Growth and Nutrient Allocation of Douglas fir Seedlings

Download or read book Growth and Nutrient Allocation of Douglas fir Seedlings written by Kim Everett and published by . This book was released on 2005* with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Regeneration of Douglas-fir following harvesting has proven difficult on many sites in British Columbia. As a result, alternative nursery practices are being explored to improve seedling growth. Using two experiments I aimed to identify an improved nutritional program for Douglas-fir seedlings. The objective of the first experiment was to identify the optimum nitrogen (N) source ratio for Douglas-fir between two inorganic sources of N, ammonium (NH4+) and nitrate (NO3- ). Seedlings were grown in controlled environments in aeroponic culture with solutions containing 0:100, 20:80, 40:60, 60:40, 80:20 or 100:0 NH4+:NO3- ratios. Growth and nutrient allocation was observed for 45 days. Different NH4+ and NO3-ratios resulted in significant differences in growth and nutrient allocation. Seedlings grown in solutions containing abundant and relatively equal portions of NH4+ and NO3- were characterized by the greatest relative growth rates, greatest biomass and stable internal nitrogen concentrations. Seedlings grown in solutions containing high NH4+ (80:20 and 100:0 NHS+:NO3- ) concentrations were characterized by lower relative growth rates, less biomass, lower internal nutrient concentrations and lower rates of photosynthesis and root respiration compared to seedlings with less NH4+ (20:80, 40:60 and 60:40 NH4+:NO3- ). Seedlings appeared to take up a greater proportion of NH4+ than NO3- from solution. The objective of the second experiment was to examine the implications of two nursery fertilization regimes for growth and nutrient dynamics. Seedlings were grown in a nursery with nutrients added at a constant rate (conventional fertilization) or at an exponentially increasing rate of 2% day-1 (exponential nutrient loading). At the time of planting, half of the conventionally fertilized seedlings were planted with slow release fertilizer packets. Growth and nutrient allocation was observed for two years following planting. In the field experiment, although exponential nutrient loading applied 25% more N in the nursery compared to the conventional regime, no benefits in growth or nutrient allocation were found. Two years after planting, there were no significant differences in height, root collar diameter or total dry mass between seedlings grown under the different nursery fertilizer regimes. In contrast, seedlings planted with additional fertilizer consistently outperformed seedlings grown with exponential nutrient loading, with greater height, root collar diameter and dry mass. Two growing seasons after planting there were no significant differences among treatments in whole-plant N concentrations.

Book Genetics of Douglas fir

Download or read book Genetics of Douglas fir written by Roy R. Silen and published by . This book was released on 1978 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book The Export Premium

Download or read book The Export Premium written by Donald F. Flora and published by . This book was released on 1993 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Growth and Nutrient Allocation of Douglas fir Seedlings

Download or read book Growth and Nutrient Allocation of Douglas fir Seedlings written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Regeneration of Douglas-fir following harvesting has proven difficult on many sites in British Columbia. As a result, alternative nursery practices are being explored to improve seedling growth. Using two experiments I aimed to identify an improved nutritional program for Douglas-fir seedlings. The objective of the first experiment was to identify the optimum nitrogen (N) source ratio for Douglas-fir between two inorganic sources of N, ammonium (NH4+) and nitrate (NO3- ). Seedlings were grown in controlled environments in aeroponic culture with solutions containing 0:100, 20:80, 40:60, 60:40, 80:20 or 100:0 NH4+:NO3- ratios. Growth and nutrient allocation was observed for 45 days. Different NH4+ and NO3-ratios resulted in significant differences in growth and nutrient allocation. Seedlings grown in solutions containing abundant and relatively equal portions of NH4+ and NO3- were characterized by the greatest relative growth rates, greatest biomass and stable internal nitrogen concentrations. Seedlings grown in solutions containing high NH4+ (80:20 and 100:0 NHS+:NO3- ) concentrations were characterized by lower relative growth rates, less biomass, lower internal nutrient concentrations and lower rates of photosynthesis and root respiration compared to seedlings with less NH4+ (20:80, 40:60 and 60:40 NH4+:NO3- ). Seedlings appeared to take up a greater proportion of NH4+ than NO3- from solution. The objective of the second experiment was to examine the implications of two nursery fertilization regimes for growth and nutrient dynamics. Seedlings were grown in a nursery with nutrients added at a constant rate (conventional fertilization) or at an exponentially increasing rate of 2% day-1 (exponential nutrient loading). At the time of planting, half of the conventionally fertilized seedlings were planted with slow release fertilizer packets. Growth and nutrient allocation was observed for two years following planting. In the field experiment, although exponential nutrient.

Book Response of Douglas Fir Seedlings to Nitrogen Sulfur and Phosphorus Fertilizers Classic Reprint

Download or read book Response of Douglas Fir Seedlings to Nitrogen Sulfur and Phosphorus Fertilizers Classic Reprint written by M. A. Radwan and published by Forgotten Books. This book was released on 2018-01-21 with total page 746 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excerpt from Response of Douglas-Fir Seedlings to Nitrogen, Sulfur, and Phosphorus Fertilizers This study, therefore, was designed to study effects of N, S, and P additions on growth and nutrient content of Douglas - fir seedlings grown in two forest soils in a lathhouse. We are aware of the limitations of pot tests in providing prescriptions that can be directly applied to field situations. However, the very limited information about Douglas - fir nutrition now available and the high cost of establishing field tests strongly justify preliminary experimentation with seedlings. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.

Book Fertilizer Abstracts

Download or read book Fertilizer Abstracts written by and published by . This book was released on 1978 with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Response of Douglas fir Seedlings to Nitrogen Sulfur and Phosphorus Fertilizers

Download or read book Response of Douglas fir Seedlings to Nitrogen Sulfur and Phosphorus Fertilizers written by M. A. Radwan and published by . This book was released on 1985 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Genetic Variation in Shoot growth Patterns of Douglas fir Populations from Southwest Oregon

Download or read book Genetic Variation in Shoot growth Patterns of Douglas fir Populations from Southwest Oregon written by Zeki Kaya and published by . This book was released on 1987 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study had three objectives: (1) to teat the hypothesis that multiple flushing of the terminal shoot (intermittent growth pattern) in Douglas-fir seedlings (Pseudotsuca menziesii var. menziesii) has an adaptive significance, especially in inland populations from the drier regions in southwest Oregon; (2) to evaluate the genetic and adaptive consequences of selecting for height increment in early testing programs; (3) to evaluate the utility of indirectly selecting for height increment by directly selecting for length and number of stem units. To accomplish objectives 1 and 2, seedling families were grown from two inland and two coastal sources (160 open-pollinated families in total) for two growing seasons in two test environments. In one environment ("dry") an intermittent moisture regime was created by withholding water during the growing season until seedlings reached -12 bars of moisture stress. Seedlings were then rewatered on a weekly schedule. In the other environment ("wet"), seedlings were watered weekly to maintain water stress of seedlings at lees than -3 bars. For objective 3. seedling families from one inland and one coastal source of Douglas-fir (80 open-pollinated families) were grown in plastic tubes for two growing seasons. Results supported the hypothesis that intermittent shoot growth is of adaptive significance in Douglas-fir in the first growing season. Shoot growth patterns varied genetically both between populations and among families within populations. As expected. families from drier inland environments, where periodic summer droughts are commons responded to the intermittent moisture regime with a higher frequency of multiple flushing. Families from coastal environments, where the moisture regime is more consisitently favorable during the growing seasons were less sensitive to the dry treatment and had a much higher frequency of seedlings which continued to grow despite the imposed drought. In the second growing season. patterns of intermittent shoot growth in inland and coastal families were not as expected. Shoot growth patterns did vary genetically between inland and coastal populations. Inland populations however, did not respond to the dry treatment with a greater frequency of multiple flushing. Apparently, inland families have adapted to drier environment and shorter growing season by relying predominantly on predetermined growth for height increment and are not able to respond to favorable growing conditions by extended free growth. Coastal families however, have developed a less regulated pattern of growth and rely more heavily on free growth for attaining height increment. The magnitude of genetic and adaptive effects of selecting for height increment in early testing programs depended on the origin of population and the environment of planting site. In inland populations early selection for total height increment mainly selects for predetermined growth. This would not lead to maladaptation in the more severe planting sites of inland southwest Oregon. Selected genotypes however would not be able to take advantage of longer growing season at favorable planting sites. In coastal populations early selection for height increment mainly selects for free growth. This may lead to maladaptation on even the favorable planting sites because with increased free growth. the length of the growth period is also increased. Slecting for length and number of stem units does not appear to be an efficient way of selecting for height increment in Douglas-fir. For this procedure to be effective, heritabilities of stem-unit measurements must be higher than heritability of height increment itself. Also genetic correlations between stem-unit measurements and height increment or its components (predetermined and free growth) must be strong. In this study, heritabilities of stem-unit measurements were small and correlations were weak.

Book Early Genetic Selection in Douglas fir

Download or read book Early Genetic Selection in Douglas fir written by Kurt H. Riitters and published by . This book was released on 1985 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis is concerned with developing techniques for identifying "superior" Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) parent trees based on seedling progeny evaluation. The growth responses of up to 14 open-pollinated families to shade, drought, and stand density were assessed in four experiments. A technique was developed to compare family height growth responses to increasing stand density while accounting for genetic variation in growth rates. Family rankings based on seedling evaluation criteria were compared with 15-year growth records for an earlier cohort from the same parent trees. The significant findings of this study were: (1) fifteen-year field height rankings were related to differences in budset date, height growth rate, and branchiness among seedlings grown with or without shade or drought stress; (2) seedling-field correlations were inversely related to seedling-seed weight correlations; (3) seedling-field correlations improved with age in the field; (L) family correlations between spaced-plant growth and closed-stand growth were low for measures of seedling size but high for measures of seedling shape, and; (5) there was genetic variation in height growth responses to increasing stand density in single-family seedling plots