Biogeochemical implications of global imbalance between the rates of marine dinitrogen (N2) fixation and denitrification have spurred us to understand the former process in the Arabian Sea, which contributes considerably to the global nitrogen budget. Heterotrophic bacteria have gained recent appreciation for their major role in marine N budget by fixing a significant amount of N2. Accordingly,...

Mutualism is of fundamental importance in ecosystems. Which factors help to keep the relationship mutually beneficial and evolutionarily successful is a central question. We addressed this issue for one of the most significant mutualistic interactions on Earth, which associates plants of the leguminosae family and hundreds of nitrogen (N2)-fixing bacterial species. Here we analyze the spatio-te...

This field experiment was established in Eastern Cameroon to examine the effect of selected rhizobial inoculation on N2-fixation and growth of Pueraria phaseoloides. Treatments consisted of noninoculated and Bradyrhizobium yuanmingense S3-4-inoculated Pueraria with three replications each. Ipomoea batatas as a non-N2-fixing reference was interspersed in each Pueraria plot. All the twelve plots ...

Plant growth is directly dependent upon an adequate supply of fixed nitrogen. Water and fixed nitrogen are the most common limiting factors for plant growth.There is an abundance of nitrogen in the atmosphere, but it is in the form of the relatively inert gas, N2, and this must be converted chemically or biologically into a more active form before plants can utilize it. Chemical fixation most c...

1.1 Biological nitrogen fixation and nitrogen nutrition in soybean plants Biological nitrogen fixation is one of the most important processes for ecosystem to access available N for all living organisms. Although N2 consists 78% of atmosphere, but the triple bond between two N atoms is very stable, and only a few group of prokaryotes can fix N2 to ammonia by the enzyme nitrogenase. Annual rate ...

The capacity of excised nodules from soybean plants to fix atmospheric N2 was demonstrated convincingly in 19521 by use of the sensitive '5N technique. Although the specific inhibitory effect of H2 on N2 fixation by nodulated red clover was discovered thirty years ago,2' 3 an understanding of the biochemistry of N2 fixation in symbionts has been delayed as a result of difficulties in obtaining ...

Although Illinois bundleflower is known to contribute N in forage systems (Dovel et al., 1990; Posler et al., Symbiotic N2 fixation capacity may affect productivity of the peren1993; Springer et al., 2001), there is a paucity of informanial legume Illinois bundleflower [Desmanthus illinoensis (Michx.) tion on its N2 fixation capability. Nodulation has been MacMill. ex B.L. Rob. & Fernald]. Our ...

Constructing nitrogen (N2) adsorption and activation sites on semiconductors is the key to achieving efficient N2 photofixation. Herein, Mn–W dual-metal WO3 are designed toward photoreduction via controlled Mn doping. Impressively, optimal 2.3% Mn-doped (Mn-WO3) exhibits a remarkable ammonia (NH3) production rate of 425 µmol gcat.?1 h?1, representing best catalytic performance among ever-report...

The amount of nitrogen gas (N2) available for microbial protein synthesis via nitrogen fixation in the rumen was estimated. Measurements were made of nitrogen fixation by ruminal ingesta from goats fed low protein rations for a prolonged period of time, and by ingesta from sheep fed high protein rations. Nitrogen fixation by rumen microorganisms incubated for 30 or 180 min in vitro was measured...