The cobalt requirement of subterranean clover in the field

1963 ◽  
Vol 14 (1) ◽  
pp. 39 ◽  
Author(s):  
PG Ozanne ◽  
EAN Greenwood ◽  
TC Shaw
Keyword(s):  
Nitrogen Fixation ◽  
Nitrogen Content ◽  
Symbiotic Nitrogen Fixation ◽  
Subterranean Clover ◽  
Applied Nitrogen

Yield increases of 30% were obtained on two subterranean clover pastures in response to dressings of 2 and 10 oz CoSO4.7H2O per acre. A dressing of salts containing chromium, nickel, vanadium, tungsten, aluminium, and iodine had no effect. Applications of cobalt increased the nitrogen content of the clover in all cases. No response to cobalt was obtained in the presence of adequate applied nitrogen. Clover growth was sharply reduced when cobalt contents fell below 0.04 p.p.m. The unfertilized soils on which the experiments were located contained only 0.022 and 0.019 p.p.m. cobalt in the 0–4 in. layer. Applied cobalt was not leached downward but remained in the surface 4 in. However, less than 0.5% of the applied cobalt was taken up by the pasture. To obtain a response to applied cobalt it appears necessary for legumes to be growing in soil containing Rhizobia capable of symbiotic nitrogen fixation; but the soil must also be very low in available cobalt and nitrogen.

Studies of seed pelleting as an aid to legume inoculation. 5. Effects of incorporation of molybdenum compounds in the seed pellet on inoculant survival, seedling nodulation and plant growth of lucerne and subterranean clover

1980 ◽  
Vol 20 (102) ◽  
pp. 63 ◽  
Author(s):  
RR Gault ◽  
J Brockwell
Keyword(s):  
Nitrogen Fixation ◽  
Plant Growth ◽  
Nitrogen Content ◽  
Significant Relationship ◽  
Storage Time ◽  
Sodium Molybdate ◽  
Subterranean Clover ◽  
Ammonium Molybdate ◽  
Molybdic Acid ◽  
Molybdenum Disulphide

Four molybdenum compounds were mixed with lime and applied as coatings to inoculated seed of lucerne (Hunter River) and subterranean clover (Mount Barker). The seed was sown immediately in molybdenum-deficient soil in the field or stored for periods up to 84 days before sowing. As storage time lengthened, the survival of both lucerne and clover rhizobia was adversely affected by sodium molybdate but not by molybdic acid, ammonium molybdate or molybdenum disulphide. This effect was reflected in poorer nodulation in the sodium molybdate treatments. Nitrogen fixation, using foliage nitrogen content as an index, was always higher in the molybdenum treatments than in the no-molybdenum controls. Both species appeared able to extract molybdenum from molybdenum disulphide. Otherwise, there were no treatment differences in plant growth, but there was a significant relationship between the proportion of seedlings nodulated by the inoculant strains and the amount of nitrogen fixation. It is concluded that seed-applied molybdenum would benefit pasture establishment in some circumstances and would not interfere with inoculant survival or seedling nodulation provided that sodium molybdate was not used for the purpose.

Nodulation and symbiotic nitrogen fixation by genotypes of blackgram [Vigna mungo (L.) Hepper] as affected by fertiliser nitrogen

2002 ◽  
Vol 53 (4) ◽  
pp. 453
Author(s):  
B. Singh ◽  
K. Usha
Keyword(s):  
Nitrogen Fixation ◽  
Symbiotic Nitrogen Fixation ◽  
Unit Area ◽  
Reductase Activity ◽  
Farming Systems ◽  
Vigna Mungo ◽  
Atmospheric Nitrogen ◽  
Nitrogen Treatments ◽  
Nitrite Content ◽  
Applied Nitrogen

Intercropping with legumes and non-legumes is commonly practised in many parts of the world to maximise productivity per unit area of land. In India, blackgram or urd [Vigna mungo (L.) Hepper] is a popular pulse legume component of intercropping farming systems. Often, however, potential production is compromised, particularly in high fertiliser input systems, because blackgram competes with the non-legume component of the system for nitrogen in the soil. In order to identify lines of blackgram that could obtain the majority of their nitrogen requirements from symbiotic fixation of atmospheric nitrogen rather than from uptake of soil nitrogen, 50 genotypes were screened for tolerance to (applied) nitrogen in soil. The parameters used to appraise tolerance were extent of root nodulation, the amount of nitrogen fixed, nitrate reductase activity in roots and nodules, and nitrite content of roots and nodules. There were 2 nitrogen treatments applied as urea, viz. 40 (N40) and 120 (N120) kg N per ha. There were 3 genotypes whose nitrogen-fixing effectiveness was apparently unimpaired by applications of nitrogen to the soil. Genotype NC-59308 nodulated and fixed atmospheric nitrogen satisfactorily at both the lower and higher levels of applied nitrogen. At N40, genotypes EC-48215 and PLU-726 formed a great abundance of large nodules effective in nitrogen fixation; even at N120, both lines had better symbioses than the majority of the 50 blackgram lines originally screened. These 3 genotypes are deemed worthy of further examination for their suitability for intercropping systems. How this might be done is discussed.

Nitrogen Nutrition of Cowpea (Vigna unguiculata)

1977 ◽  
Vol 13 (3) ◽  
pp. 241-252 ◽  
Author(s):  
P. J. Dart ◽  
P. A. Huxley ◽  
A. R. J. Eaglesham ◽  
F. R. Minchin ◽  
R. J. Summerfield ◽  
...  
Keyword(s):  
Nitrogen Fixation ◽  
Vigna Unguiculata ◽  
Symbiotic Nitrogen Fixation ◽  
Nitrogen Nutrition ◽  
Combined Nitrogen ◽  
Nitrogen Treatments ◽  
Seed Yields ◽  
Applied Nitrogen

SUMMARYAverage seed yields of effectively nodulated cowpea plants were 38% greater than those of non-nodulated plants when both received applied nitrogen at concentrations ranging from 60 to 240 ppm during one of three periods: emergence to first flower, first flower to mid pod-fill, or mid pod-fill to maturity. Nodulation increased seed yields by 45% when plants received a ‘basal’ level of 30 ppm N throughout growth. None of the combined nitrogen treatments could compensate non-nodulated plants for the loss of symbiotic nitrogen fixation. Non-nodulated plants relying on applied N branched less, produced fewer peduncles and set fewer pods on each peduncle than nodulated plants.

Effect of nitrogen and cobalt application on herbage and seed yields of serradella and subterranean clover

1985 ◽  
Vol 25 (3) ◽  
pp. 588 ◽  
Author(s):  
MDA Bolland
Keyword(s):  
Nitrogen Fixation ◽  
Field Experiment ◽  
Nitrogen Fertilizer ◽  
Dry Matter ◽  
Symbiotic Nitrogen Fixation ◽  
Subterranean Clover ◽  
Fertilizer Nitrogen ◽  
Matter Production ◽  
Winter Temperatures ◽  
Seed Yields

The response of serradella and subterranean clover to soil applications of cobalt in the absence and presence of regular applications of nitrogen fertilizer was measured in a field experiment on a nitrogen-deficient soil near Esperance, Western Australia. In an ancillary experiment, also sited near Esperance on a nitrogen-deficient soil, the responses of three serradella species and two cultivars of subterranean clover to regular applications of nitrogen were measured. Yields of herbage and seed were used to measure the response to the fertilizer treatments. Neither serradella, nor subterranean clover responded to cobalt application. However, in winter, herbage yields of serradella were markedly improved by regular applications of fertilizer nitrogen. Yield increases were three- to eight-fold, depending on the species. However, by springtime, there was no herbage response of serradella to fertilizer nitrogen. Seed yields of serradella and yields of subterranean clover at any harvest were unaffected by regular applications of nitrogen. It is concluded that low winter temperatures limit the rate of symbiotic nitrogen fixation for serradella which in turn limits dry matter production.

Nitrogen Nutrition of Cowpea (Vigna unguiculata). I. Effects of Applied Nitrogen and Symbiotic Nitrogen Fixation on Growth and Seed Yield

1977 ◽  
Vol 13 (2) ◽  
pp. 129-142 ◽  
Author(s):  
R. J. Summerfield ◽  
P. J. Dart ◽  
P. A. Huxley ◽  
A. R. J. Eaglesham ◽  
F. R. Minchin ◽  
...  
Keyword(s):  
Nitrogen Fixation ◽  
Seed Yield ◽  
Vigna Unguiculata ◽  
Symbiotic Nitrogen Fixation ◽  
Nitrogen Nutrition ◽  
Seed Yields ◽  
Applied Nitrogen

SUMMARYEffectively nodulated cowpea plants, grown in pots without applied nitrogen, were vegetatively equal to non-nodulated plants supplied with 60 ppm N throughout growth (88 days) and produced significantly greater seed yields. Supplying non-nodulated plants with 120 or 240 ppm N improved seed yields (but not significantly) compared with plants completely dependent on symbiotic fixation. Nodulation promoted branching, and improved pod set and/or retention compared with plants relying on applied N.

scholarly journals Plasmids Related to the Symbiotic Nitrogen Fixation Are Not Only Cooperated Functionally but Also May Have Evolved over a Time Span in Family Rhizobiaceae

2020 ◽  
Vol 12 (11) ◽  
pp. 2002-2014
Author(s):  
Ling-Ling Yang ◽  
Zhao Jiang ◽  
Yan Li ◽  
En-Tao Wang ◽  
Xiao-Yang Zhi
Keyword(s):  
Nitrogen Fixation ◽  
Gene Transfer ◽  
Horizontal Gene Transfer ◽  
Symbiotic Nitrogen Fixation ◽  
Gene Families ◽  
Time Span ◽  
Soil Conditions ◽  
Gene Gain ◽  
Nitrogen Fixing ◽  
Pan Genome

Abstract Rhizobia are soil bacteria capable of forming symbiotic nitrogen-fixing nodules associated with leguminous plants. In fast-growing legume-nodulating rhizobia, such as the species in the family Rhizobiaceae, the symbiotic plasmid is the main genetic basis for nitrogen-fixing symbiosis, and is susceptible to horizontal gene transfer. To further understand the symbioses evolution in Rhizobiaceae, we analyzed the pan-genome of this family based on 92 genomes of type/reference strains and reconstructed its phylogeny using a phylogenomics approach. Intriguingly, although the genetic expansion that occurred in chromosomal regions was the main reason for the high proportion of low-frequency flexible gene families in the pan-genome, gene gain events associated with accessory plasmids introduced more genes into the genomes of nitrogen-fixing species. For symbiotic plasmids, although horizontal gene transfer frequently occurred, transfer may be impeded by, such as, the host’s physical isolation and soil conditions, even among phylogenetically close species. During coevolution with leguminous hosts, the plasmid system, including accessory and symbiotic plasmids, may have evolved over a time span, and provided rhizobial species with the ability to adapt to various environmental conditions and helped them achieve nitrogen fixation. These findings provide new insights into the phylogeny of Rhizobiaceae and advance our understanding of the evolution of symbiotic nitrogen fixation.

scholarly journals Antioxidation and symbiotic nitrogen fixation function of prxA gene in Mesorhizobium huakuii

2019 ◽  
Vol 8 (10) ◽  
Author(s):  
Sanjiao Wang ◽  
Tiantian Lu ◽  
Qiang Xue ◽  
Ke Xu ◽  
Guojun Cheng
Keyword(s):  
Nitrogen Fixation ◽  
Symbiotic Nitrogen Fixation ◽  
Mesorhizobium Huakuii
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