Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Added nitrogen interaction  (3)
  • Somatic hybrid  (3)
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Biology and fertility of soils 20 (1995), S. 41-48 
    ISSN: 1432-0789
    Keywords: Added nitrogen interaction ; Ammonia fixation ; 15N ; Immobilization ; Fertilizer-induced solubilization
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Added N interactions were measured in four soil incubated with 15N-labelled urea or diammonium phosphate. The use of biologically active, γ-irradiated, or reinoculated γ-irradiated samples allowed us to separate added N interactions due to chemical and biological processes, and to distinguish real interactions from apparent effects. Real biologically mediated added N interactions were observed in one soil for both fertilizer sources and in three soils amended with urea. These real interactions increased with the N fertilizer rate, but did not differ significantly between N sources. Fertilizer-induced unlabelled organic N in soil extracts declined during incubation in both sterile and non-sterile samples, but the temporal decline was higher in biologically active soil. Changes in fertilizer-induced unlabelled organic N in the extracts of three soils attributed to biological processes were similar to the measured real biologically mediated added N interactions. The results are consistent with the hypothesis that real biologically mediated added N interactions arise from the mineralization of soil organic N solubilized by alkaline-hydrolysing N fertilizers.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Biology and fertility of soils 23 (1996), S. 93-98 
    ISSN: 1432-0789
    Keywords: Added nitrogen interaction ; Alkaline-hydrolysing fertilizer ; Aqua ammonia ; Gross N immobilization ; Gross N mineralization ; 15N ; Soluble organic N availability
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Organic N solubilized by NH3(aq) was extracted from 15N-labelled or unlabelled soil, concentrated and added to non-extracted soil, which was incubated under aerobic conditions at 27±1°C. Gross N mineralization, gross N immobilization, and nitrification in soils with or without addition of unlabelled soluble organic N were estimated by models based on the dilution of the NH 4 + or NO inf3 sup- pools, which were labelled with 15N at the beginning of incubation. Mineralization of labelled organic N was measured by the appearance of label in the mineral N pool. Although gross N mineralization and gross N immobilization were increased in two soils between day 0 and day 7 following addition of unlabelled organic N solubilized by NH3(aq), there was no increase in net N mineralization. Solubilization of 15N-labelled organic N increased and the 15N enrichment of the soluble organic N decereased as the concentration of NH3(aq) added increased. A constant proportion of approximately one-quarter of the labelled organic N added at different rates to non-extracted soil was recovered in the mineral N pool after an incubation period of 14 days, and the availability ratios calculated from net N mineralization data were 1.1:1 and 2.1:1 for 111 and 186 mg added organic-N kg-1 soil, respectively, indicating that the mineralization of organic N was increased by solubilization.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical and applied genetics 76 (1988), S. 915-922 
    ISSN: 1432-2242
    Keywords: Intergeneric somatic hybridisation ; Brassica ; Diplotaxis ; Somatic hybrid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The need to transfer genetic traits from Diplotaxis muralis (2n=42) to Brassica juncea (2n=36), a major oil seed crop of the tropical world, was realised. Since the two plant types are sexually incompatible, attempts were made to evolve parasexual hybrids as the result of protoplast fusion. Protoplasts of hypocotyl-derived calli of two cultivars of B. juncea were fused with normal and γ-irradiated mesophyll protoplasts of Diplotaxis muralis. Regeneration of 110 plants from the fused products was successfully achieved. Upon analysis of some of them, we realised that true somatic hybrids and partial somatic hybrids had been generated. Thus the primary goal of evolving intergeneric hybridisation products between these two plant types was fulfilled.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 1432-2242
    Keywords: Intergeneric somatic hybridization ; Brassica + Eruca ; Somatic hybrid ; Partial somatic hybrid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Hypocotyl calli-derived protoplasts of two cultivars of Brassica juncea (2n=36), a major oil-seed crop, were fused with normal as well as γ-irradiated mesophyll protoplasts of Eruca sativa (2n=22). The irradiation of the Eruca fusion partner increased the plating efficiency as well as the morphogenic potentiality of the fusion products over the normal fusion. Fertile plants could be regenerated from such fusion products. Analysis of 63 out of 181 plants regenerated showed that, indeed, 11 somatic hybrids (2n=58) and 10 partial somatic hybrids (chromosome number ranged between 50 and 56) had been obtained. Pollen viability (0%–82.9%) and seed set (0%–50%) of the hybrids indicated them to be useful for future studies.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1432-2242
    Keywords: Protoplast fusion ; Somatic hybrid ; Brassica juncea ; Diplotaxis harra ; Wild gene transfer
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract An attempt to transfer genes from droughttolerant Diplotaxis harra, a wild relative of Brassica species, to an elite oil-yielding cultivar, B-85, of mustard (Brassica juncea) was made through protoplast fusion, as the two plant systems are sexually incompatible. By following the standard protocol for PEG-mediated protoplast fusion followed by high pH, high Ca++, DMSO treatment and appropriate cell-culture technique, 16 presumptive somatic hybrid plants could be regenerated. Chromosomal analysis of four such somatic hybrids revealed that three of them were asymmetric. Analysis of morphological characters, meiotic chromosomes, and esterase isoenzyme pattern revealed that all the somatic hybrids were different from each other. Furthermore four chromosomes of each genome could undergo homoeologous pairing at meiosis indicating the possibilities for genetic recombination and chromosomal rearrangements. Irregular distribution of chromosomes at anaphase-II at meiosis has been a consistent feature of these plants. Eventually, pollen of all the somatic hybrids showed complete infertility preventing the recovery of any selfed seed. Nevertheless, ovule fertility of one somatic hybrid was not totally impaired as it had set some seeds upon backcrossing with the B. juncea parent. The esterase isoenzyme banding pattern of 24 individual progeny plants of this backcross provided evidence for their recombinant nature. It was thus confirmed that a transfer of genetic traits from Diplotaxis harra to B. juncea had indeed taken place. Furthermore, it was conceptualised that a transfer of alien genes through the protoplast-fusion technique is primarily possible in situations where meiotic pairing of the chromosomes of the two participating genomes generates recombinant gametocytes which can pass through subsequent filial generations.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Nutrient cycling in agroecosystems 36 (1993), S. 239-248 
    ISSN: 1573-0867
    Keywords: Added nitrogen interaction ; alkaline hydrolysis ; ammonia fixation ; aqua ammonia ; di-ammonium phosphate ; fertilizer-induced deamination ; urea
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Chemical interactions between soil N and alkaline-hydrolysing N fertilizers labelled with15N were studied in the laboratory using twelveγ-irradiated soils. Fertilizer was recovered in the soil organic N fraction via the process of NH3 fixation. NH3 fixation at day 7 varied from 1.8 to 4.6% of the N added as aqua ammonia at 1000 mg kg−1 soil. The amount of NH3 fixed increased with increasing rates of application of NH3(aq) and urea. The rate of NH3 fixation decreased with time, with more than 55% of the total NH3 fixation in 28 days occurring in the first week following application of 2000 mg urea-N kg−1 soil. Soil pH and NH3 fixation varied in response to N source, and increased in the order of di-ammonium phosphate 〈urea 〈 aqua ammonia at equivalent N concentrations. The alkaline hydrolysis of indigenous organic N occurred simultaneously with NH3 fixation, resulting in the release of unlabelled ammonium (deamination) and a real added nitrogen interaction in all but two of the soils studied. The release of NH 4 + initially increased up to a pH of 7.5, was inhibited between pH 8.5 and 9.0, but increased thereafter. The balance (Nbal) between NH3 fixation and deamination was either positive or negative, depending on the pH of the fertilized soil, which was directly related to N source and concentration for a given soil.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...