Effect of ammonium nitrate on nodulation and nitrogen fixation (acetylene reduction) of the tropical legume Sesbania rostrata
01 Sep 1987-Vol. 3, Iss: 3, pp 235-241
TL;DR: Stem and root acetylene reduction were strongly inhibited by high mineral nitrogen concentrations; however root nitrogen fixation was more affected than stem nitrogen fixation, and stem nodulation was inhibited.
Abstract: The effect of ammonium nitrate on nodulation and nitrogen fixation (acetylene reduction activity) was investigated usingSesbania rostrata, a tropical legume with the ability to nodulate both roots and stems. Plants were grown in plastic pots on silica sand and gravel, inoculated one month after sowing and then continuously irrigated with an automatic irrigation system. Four nitrogen treatments were applied: 0, 1.5, 3.0 and 6.0mm NH4NO3. Related symbiotic parameters were evaluated 20 days later. With 3.0mm NH4NO3, root nodulation was inhibited. At that concentration, stem nodulation was not affected, but related nitrogenase activity decreased 85% and was completely inhibited at 6.0mm NH4NO3. Increasing NH4NO3 concentration resulted in a diminution of stem nodule size. Stem and root acetylene reduction were strongly inhibited by high mineral nitrogen concentrations; however root nitrogen fixation was more affected than stem nitrogen fixation.
Citations
More filters
TL;DR: This last property, together with its host-specific symbiotic nitrogen fixation, makes Azorhizobium highly specialized for stem nodulation of the aquatic legume Sesbania rostrata.
Abstract: Sesbania species can establish symbiotic interactions with rhizobia from two taxonomically distant genera, including the Sesbania rostrata stem-nodulating Azorhizobium sp. and Azorhizobium caulinodans and the newly described Sinorhizobium saheli and Sinorhizobium teranga bv. sesbaniae, isolated from the roots of various Sesbania species. A collection of strains from both groups were analyzed for their symbiotic properties with different Sesbania species. S. saheli and S. teranga bv. sesbaniae strains were found to effectively stem nodulate Sesbania rostrata, showing that stem nodulation is not restricted to Azorhizobium. Sinorhizobia and azorhizobia, however, exhibited clear differences in other aspects of symbiosis. Unlike Azorhizobium, S. teranga bv. sesbaniae and S. saheli did not induce effective stem nodules on plants previously inoculated on the roots, although stem nodulation was arrested at different stages. For Sesbania rostrata root nodulation, Sinorhizobium appeared more sensitive than Azorhizobium to the presence of combined nitrogen. S. saheli and S. teranga bv. sesbaniae were effective symbionts with all Sesbania species tested, while Azorhizobium strains fixed nitrogen only in symbiosis with Sesbania rostrata. In a simple screening test, S. saheli and S. teranga bv. sesbaniae were incapable of asymbiotic nitrogenase activity. Thus, Azorhizobium can easily be distinguished from Sinorhizobium among Sesbania symbionts on the basis of symbiotic and free-living nitrogen fixation. The ability of Azorhizobium to overcome the systemic plant control appears to be a stem adaptation function. This last property, together with its host-specific symbiotic nitrogen fixation, makes Azorhizobium highly specialized for stem nodulation of the aquatic legume Sesbania rostrata.
34 citations
Cites background from "Effect of ammonium nitrate on nodul..."
...Compared to root nodulation, stem nodulation and related N2 fixation are less inhibited by combined nitrogen (7, 19)....
[...]
...caulinodans system (19), is still poorly understood (27, 28)....
[...]
01 Jan 2019
TL;DR: This work focuses on the taxonomy, biodiversity, ecology and evolution of rhizobia, and the role of symbiosis genes in this taxonomy and evolution.
Abstract: Preface -- Chapter 1. Symbiosis between rhizobia and legumes -- Chapter 2. History of rhizobial taxonomy -- Chapter 3. Current Systematics of rhizobia -- Chapter 4. Genomics and evolution of rhizobia -- Chapter 5. Symbiosis genes: diversity and organization -- Chapter 6. Evolution of symbiosis genes: Vertical and horizontal gene transfer -- Chapter 7. Diversity of interactions between rhizobia and legumes -- Chapter 8. Geographical distribution of rhizobia -- Chapter 9. Environmental determinants of biogeography of rhizobia -- Chapter 10. Effects of host plants on biogeography of rhizobia -- Chapter 11. Rhizobial genomics and biogeography -- Chapter 12. Current status of rhizobial inoculants -- Chapter 13. Screening for effective rhizobia -- Chapter 14. Usage of rhizobial inoculants in agriculture -- Chapter 15. Rhizobial activity beyond nitrogen fixation -- Chapter 16. Working on the taxonomy, biodiversity, ecology and evolution of rhizobia -- Index -- Acknowledgments.
30 citations
01 Jan 2007
TL;DR: In this article, the authors focus on small-scale rice farmers in Northern Thailand to understand the social and technical relations involved in rice based farming systems, and to illuminate scope for participatory technology development more generally.
Abstract: Keywords: small-scale rice farmers, collective action, community rice seed, local innovations, green manure crop, contract farming, participatory technology development, up-scaling, technological configuration, grid-group theory, Northern Thailand Many small-scale rice farmers practise collective action to overcome production constraints, and to generate and redistribute benefits for maintaining improved household livelihoods. The practice is particularly important for small-scale rice farmers in Northern Thailand where rice-based livelihood diversification prevails. The thesis seeks to build an understanding of farmer capacity in cooperation, as well as to identify crucial enabling factors that stimulate collective action to enhance continued learning and adaptation for sustainable development, via analysis of group attributes in relation to four sets of elements: agro-ecological conditions, socio-economic variables, cultural context and the role of government intervention. The study focuses on small-scale rice farming in Northern Thailand , with the aim to understand the social and technical relations involved in rice based farming systems, and to illuminate scope for participatory technology development more generally. This thesis targets rice farmers because of their important contribution to the country's food security and social economic development. The research was carried out during 2003- 2005 in a village with viable forms of collective action (Dong Palan, DPL) and in another village (Buak Mue, BM), included for comparative purposes, where off-farm employment affects labour use and household composition in such a way that collective action eroded or has a different orientation. Both qualitative and quantitative methods were used for data collection. Semi-structured interviews of key informants, group meetings, focus group discussion, farmer workshops and participant observation were all employed. The collective action was explored under four case studies including (i) community rice seed production scheme, (ii) local innovations in rice farming (frog protection as integrated pest management practice, modification of weed slashing machine as hand-held rice harvesting equipment, and double rice transplanting technique), (iii) participatory technology development in green manure crop, and (iv) contract farming. There are various forms of collective actions, and the forms suitable for technology development depend on social and material circumstances in the local context. The varying organizational forms of collective action reveal a hybridity of institutional modalities, which is further described, using grid-group theory, by the level of regulation of individual behaviour and the level of absorption of individuals in group memberships. The most important institutional and individual mechanisms are flexible forms of benefit sharing, recognizing and managing common interests, trust building, and finally, joint problem solving and knowledge exchange among farmers themselves and between farmers and external agencies. This thesis evidently shows that effective technology development and agro-technological innovation depend on social relationships and, more specifically, on the capacity to link to existing forms of collective action. Technology that works is a configuration resulting from a combination of agro-ecological conditions, technological artifacts and social arrangements, including collective action. The incentive for people to participate in technology development as well as the management and development of resources is a major enabling factor for sustainable collective action. In addition, collective knowledge can make an important contribution to technology development and innovation so that people with long experiential learning from trial and error in rice farming are able to integrate their own knowledge with outside knowledge in developing technology. This thesis indicates that horizontal up-scaling worked in the context of DPL which exhibits good social networking among farmers, but not in BM village. The observed variety in organizational forms and social coherence leads to an important lesson for the practice of participatory technology development, namely that attractive technologies may be incommensurable with realities in rural economies. Hence, an insight from this thesis is that constructing a fit-for-all model of collective action for small-scale and sustainable technologies may not be desirable because of the different social and material conditionalities in the field.
16 citations
Cites background from "Effect of ammonium nitrate on nodul..."
...1981), and appears as a probable adaptive response to waterlogging this ability confers on this legume an advantage assimilating both soil and atmospheric nitrogen (Moudiongui and Rinaudo, 1987)...
[...]
01 Jan 2019
TL;DR: In this chapter, the history and current status of rhizobial inoculation application around the world are reviewed briefly, the strategy for screening and choosing effective rhizobia, preparation of inoculant and application in agriculture for specific legumes are discussed.
Abstract: In this chapter, the history and current status of rhizobial inoculation application around the world are reviewed briefly. Then, the strategy for screening and choosing effective rhizobia, preparation of inoculant and application in agriculture for specific legumes are discussed. Next, some microelements and biostimulants are proposed to be used together with rhizobial inoculants to enhance symbiotic nitrogen fixation. Finally, the other roles of rhizobia beyond nitrogen fixation are discussed.
5 citations
References
More filters
TL;DR: Nodulated plants of field pea were grown for 4 weeks in a range of constantly maintained levels of nitrate labelled with N15 to study the plant response to nitrate, and the distribution of the nitrogen assimilated from nitrate and from the atmosphere was assessed.
Abstract: Nodulated plants of field pea (Pisum arvense L.) were grown for 4 weeks in a range of constantly maintained levels of nitrate labelled with N15. The total and labelled nitrogen in soluble and insoluble fractions of different parts of the treated plants were determined, and from such measurements the distribution of the nitrogen assimilated from nitrate and from the atmosphere was assessed.
69 citations
TL;DR: A single inoculation of the stems of Aeschynomene plants with the rhizobial strain BTAi 1 induced the formation of green N 2 -fixing nodules visible within 8 days, induced to occur in the greenhouse also on non-flooded plants.
67 citations
TL;DR: Stem nodules of the legume Sesbania rostrata are ovoids, contain chlorophyll and have determinate growth and there is an intracellular release of Rhizobia by an endocytotic process.
Abstract: Stem nodules of the legume Sesbania rostrata are ovoids, contain chlorophyll and have determinate growth. They possess a large central mass of infected cells. Stem mamillae are regularly arranged i...
61 citations
TL;DR: It is concluded that combined nitrogen affects symbiotic nitrogen fixation via the carbohydrate supply to the bacteroids through the acetylene-reducing activity of isolated bacteroids.
Abstract: Addition of ammonium chloride or potassium nitrate to nodulated pea plants resulted in a decrease in acetylene-reducing activity. Both nodule growth and specific activity of the nodules were diminished. Acetylene-reducing activity of isolated bacteroids, treated with EDTA-toluene and supplied with ATP and dithionite, had not decreased after a 3-day treatment of the plants with NH4Cl or KNO3. The effect of combined nitrogen could be counteracted by raising the light intensity or by the addition of sucrose to the growth medium. The latter treatment reduced the nitrogen uptake by the plants. It is concluded that combined nitrogen affects symbiotic nitrogen fixation via the carbohydrate supply to the bacteroids.
47 citations
TL;DR: The results indicate that the added sugars alleviated the inhibitory effects of nitrates on symbiotic nitrogen fixation not only by increasing the carbohydrate supply so lentils could support both nitrogen fixation and nitrate reduction but also by inhibiting the accumulation of nitrate and, hence, lowering nitrate reductase activity in the leaves.
Abstract: Lentils (Lens esculenta Moench, cv. Tekoas) grown in a nutrient solution containing 15 millimolar nitrate had 84% fewer nodules than lentils grown in nitrate-free nutrient solution. Nodules from the nitrate-grown plants weighed 71% less than nodules from the nitrate-free plants. Nitrate-grown plants also fixed much less nitrogen (measured by acetylene reduction) than the nitrate-free plants. When lentils were grown in a solution containing 15 millimolar nitrate and 75 millimolar fructose, glucose, or sucrose, however, the nitrogen fixation activity of their nodules was similar to that of nodules from nitrate-free plants. Leaves of lentils grown in the nitrate-sugar solutions had only about 7% as much nitrate reductase activity and accumulated only 10% as much nitrate as leaves from lentils grown in the nitrate solution alone. Roots of lentils grown in the nitrate-sugar solutions had similar nitrate reductase activity but accumulated only 17 to 25% as much nitrate as roots from lentils grown in the nitrate solution. The results indicate that the added sugars alleviated the inhibitory effects of nitrate on symbiotic nitrogen fixation not only by increasing the carbohydrate supply so lentils could support both nitrogen fixation and nitrate reduction but also by inhibiting the accumulation of nitrate and, hence, lowering nitrate reductase activity in the leaves.
39 citations