Author: Kathleen Ann FishbeckPublisher:
ISBN:
Category :
Languages : en
Pages : 162
Book Description
Symbiotic Nitrogen Fixation in Alfalfa (Medicago Sativa L.) During Vegetative Regrowth
Author: Kathleen Ann FishbeckPublisher:
ISBN:
Category :
Languages : en
Pages : 162
Book Description
Symbiotic Nitrogen Fixation in Alfalfa (Medicago Sativa L.) During Vegetable Regrowth
Author: Kathleen Ann FishbeckPublisher:
ISBN:
Category :
Languages : en
Pages : 72
Book Description
Statistical Evaluation of Factors Affecting Symbiotic Nitrogen Fixation by Alfalfa (Medicago Sativa L.) and Soybean (Glycine Max Merr.)
Author: Ceferino Jucutan MartinezPublisher:
ISBN:
Category :
Languages : en
Pages : 552
Book Description
Inferencias estatisticas foram usadas para avaliar fatores que afetam a fixacao simbiotica de nitrogenio por alfafa (Medicago sativa L.) e soja (Glycine max Merr.). No estudo foram incluidos os efeitos de niveis de inoculacao, numero de inoculacao sobre a eficiencia simbiotica.
The Interactive Effects of Water Salinity and Management on Symbiotic Nitrogen Fixation in Alfalfa
Author: Thomas J. KeckPublisher:
ISBN:
Category : Alfalfa
Languages : en
Pages : 200
Book Description
A greehhouse study was conducted to assess the interactive effects of three irrigation water salinity levels (1. 0, 3. 0, and 9. 0 mmho/cm) and three quantities of water app lied per irrigation (120, 240, 360 ml) on plant growth and nitrogen fixation by alfalfa (Medicago sativa L. cv. Resistador). Harvest dates corresponded t o 10, 30, and 50 days after the initiation of salt and water treatments which were started after nodulation had been established in young plants. Alfalfa top growth was limited by both salt and water s tresses. Irrigation water s alinity had a grea t er effec t on top growt h than root grm;th while root distribution was unaffected by either the quant i ty of water app l ied or by water salinity. The effects of salinity on pl ant growth were reduced in the presence of l imi ting moisture. The specific nodul e act ivi t y (mmol c2H4/hr/g) of water s tressed alfalfa pl ants was enhanced by increasing the quantity of wat er applied a t each irriga t ion and was adversely effected by increased irrigation water salinity. In contrast, both nodulation and nodule growth were insensitive t o salt stress and sensi tive only to severe mo i s ture s tress. Alfalfa plants continued to exhibit acetylene reducing capacity at the third harvest even under severe moisture and salt stress. The species apparently continues to fix nitrogen even though environmental stress is quite substantial.
Host Plant Metabolism of Symbiotically Fixed Nitrogen in Alfalfa (Medicago Sativa L.) Root Nodules
Author: Randall Gene GroatResponse of N2-fixation in Alfalfa to Combined Nitrogen Additions
Author: Christopher Joseph PostPublisher:
ISBN:
Category :
Languages : en
Pages : 224
Book Description
Growth, Nodulatin and Nitrogen Fixation of Alfalfa (Medicago Sativa L.) and Red Clover (Trifolium Pratense L.) as Influenced by Soil Acidity and Liming
Author: Daniel Stewart Thomas RobertsPublisher:
ISBN:
Category : Alfalfa
Languages : en
Pages : 320
Book Description
The Effect of Preplant Nitrogen Fertilization and Soil Temperature on Biological Nitrogen Fixation and Yield of Alfalfa (Medicago Sativa L.)
Author: Philip E. ShulerPublisher:
ISBN:
Category : Alfalfa
Languages : en
Pages : 170
Book Description
The usefulness of preplant nitrogen (N) in establishing alfalfa in colder production areas has not been well characterized. This study was conducted to determine the effect of preplant N and soil temperature on yield, percent N derived from biological nitrogen fixation (PBNF), and shoot N concentration in alfalfa (Medicago sativa L. cv. 'Vernema'. Field experiments were conducted in 1987 and 1988 at Powell Butte, OR, to determine the effect of five levels of preplant N (0, 10, 20, 40, 60 kg ha−1) on yield and shoot N concentration of alfalfa. Growth chamber experiments were conducted from 1989 through 1991 to examine the effect of five levels of preplant N (0, 10, 20, 40, 80 kg ha−1) and three day/ - night soil temperatures (18/12°C, 24/16°C, 27/21°C) on yield, PBNF, and shoot N concentration of alfalfa. In field experiments, preplant N had no effect on shoot N concentration in either year. In 1987 there was no effect of preplant N on dry matter yield. Application of 20-40 kg N ha−1 preplant N increased dry matter yield in 1988. In growth chamber experiments, the highest rate of dry matter accumulation occurred at a soil temperature of 24/16°C. At 18/12°C and 24/16°C, 40 kg ha−1 preplant N resulted in increased shoot and root dry matter yield. At 18/12°C, 80 kg ha-1 preplant N increased PBNF 14% relative to the zero N control. There was no effect of preplant N on PBNF in plants grown at 24/16°C and 27/- 21°C. The rates of shoot N accumulation were similar at 18/12°C and 24/16°C, and were higher than at 27/21°C. Shoot N concentration was not affected by preplant N treatments. The use of 20-40 kg ha−1 preplant N may result in increased yield without decreasing PBNF when: 1) soil temperature remains below 15°C for at least two weeks after planting, and 2) soil nitrate level is less than 16 mg kg−1. Proper assessment of the use of preplant N in alfalfa establishment requires a careful consideration of both soil temperature and soil N availability.
Improvement of the Nitrogen Fixation Potential in Alfalfa (Medicago Sativa L.)
Author: David L. HoffmanPublisher:
ISBN:
Category : Alfalfa
Languages : en
Pages : 60
Book Description
Symbiotic Nitrogen Fixation
Author: P. GrahamPublisher: Springer Science & Business Media
ISBN: 9401110883
Category : Science
Languages : en
Pages : 206
Book Description
During the past three decades there has been a large amount of research on biological nitrogen fixation, in part stimulated by increasing world prices of nitrogen-containing fertilizers and environmental concerns. In the last several years, research on plant--microbe interactions, and symbiotic and asymbiotic nitrogen fixation has become truly interdisciplinary in nature, stimulated to some degree by the use of modern genetic techniques. These methodologies have allowed us to make detailed analyses of plant and bacterial genes involved in symbiotic processes and to follow the growth and persistence of the root-nodule bacteria and free-living nitrogen-fixing bacteria in soils. Through the efforts of a large number of researchers we now have a better understanding of the ecology of rhizobia, environmental parameters affecting the infection and nodulation process, the nature of specificity, the biochemistry of host plants and microsymbionts, and chemical signalling between symbiotic partners. This volume gives a summary of current research efforts and knowledge in the field of biological nitrogen fixation. Since the research field is diverse in nature, this book presents a collection of papers in the major research area of physiology and metabolism, genetics, evolution, taxonomy, ecology, and international programs.