Showing papers on "Frankia published in 1982"
TL;DR: Using the OsO4 isolation method, Frankia strains were obtained from 27 provenances of the two alder species represented in Quebec and the sporulating or nonsporulating endophytic character was recognized as one of the valid criteria that should be used in the awaited species definition in the genus Frankia.
Abstract: Using the OsO4 isolation method, more than 200 Frankia strains were obtained from 27 provenances of the two alder species represented in Quebec, i.e., Alnus crispa (Ait.) Pursh. and Alnus rugosa (D...
204 citations
TL;DR: Using the simple serial dilution technique, five strains of actinomycetes were isolated from nodules of Casuarina equisetifolia and were assumed to belong to the genus Frankia because they possessed the morphological and cultural characteristics now admitted as specific to this genus.
Abstract: Using the simple serial dilution technique, five strains of actinomycetes were isolated from nodules of Casuarina equisetifolia. In spite of the fact that these strains did not nodulate the host pl...
86 citations
TL;DR: A simple procedure, based on the rapid filtration and washing of Frankia vesicle clusters, was devised for the isolation of Frankian strains from alder actinorhizal root nodules and is an improved method for the study ofFrankia diversity in alder root nodule.
Abstract: A simple procedure, based on the rapid filtration and washing of Frankia vesicle clusters, was devised for the isolation of Frankia strains from alder actinorhizal root nodules. Of 46 Alnus incana subsp. rugosa nodules prepared, 42 yielded isolates. A simple medium containing mineral salts, Casamino Acids, and sodium pyruvate proved to be the most effective for isolation. In general, colonies appeared 6 to 20 days after inoculation. On the basis of hyphal morphology, two distinct types of Frankia strains were characterized. Randomly selected isolates were tested for infectivity, and all formed root nodules on A. glutinosa. Because of its simplicity and efficiency, the procedure is an improved method for the study of Frankia diversity in alder root nodules.
75 citations
TL;DR: A pattern of compatibilities among hosts and endophytes was developed to explain differences in rates of acetylene reduction, which suggested that endophyte were not fully compatible with some or all of the host plants tested.
Abstract: SUMMARY
Frankia strains ArI5, AvcIl, AvsI2, CpI1 and MpI1, previously isolated from nodules of actinorhizal plants, were tested in association with various actinorhizal plants to determine differences in nitrogen-fixing effectiveness. Alnus incana ssp. rugosa, Alnus rubra, Alnus viridis ssp. crispa, Comptonia peregrina and Myrica gale plants, grown in nitrogen-free water culture, were inoculated with the cultured Frankia strains. Significant differences in rates of acetylene reduction were found among strains which suggested that endophytes were not fully compatible with some or all of the host plants tested. A pattern of compatibilities among hosts and endophytes was developed to explain differences in rates of acetylene reduction.
65 citations
TL;DR: The growth of Frankia isolates was monitored by dry weight, total protein and total ATP measurements under different temperature and pH regimes and significant correlations were found among all growth measures.
Abstract: The growth of Frankia isolates was monitored by dry weight, total protein and total ATP measurements under different temperature and pH regimes. Significant correlations (P<0.01) were found among all growth measures which meant that similar general conclusions were reached irrespective of the study method involved. The assessment of protein was the method of choice for regular assessments of Frankia growth due to its facility and relatively high sensitivity. The optimum temperature for growth of isolate LDAgp1 and AvcI1 was about 30°C while for CpI1 it lay between 30° and 35°C. No growth was observed at 40°C but some growth was observed at 10°C with isolate CpI1 and LDAgp1 over an extended growth period of 39 days. The range of pH favouring growth lay between 6 and 8. The optimum for LDAgp1 lay between 6.5 and 7, that for AvcI1 and CpI1 is close to 6.5. The pH response was medium dependent. Increases in biomass were observed for some isolates at 4.6 and above 8.0 on some media.
59 citations
TL;DR: Observed here are observations indicating that Frankia is able to grow outside the nodule of Casuarina equisetifolia and to proliferate in its vicinity.
Abstract: 17 genera of non-leguminous angiosperms bear NI-fixing root nodules initiated by an actinomycete known as Frankia [1,11]. The expanding volume of current literature attests to the significance vested in this symbiosis. However, to the best of our knowledge, no publications up to this point have dealt with the occurrence and behaviour of Frankia outside its specific niche, the nodule. Reported here are observations indicating that Frankia is able to grow outside the nodule of Casuarina equisetifolia and to proliferate in its vicinity. Our study is focused on Casuarina because these tropical and subtropical non-legumes play a major role by virtue of their ability to thrive on nitrogen-deficient soils.
27 citations
TL;DR: Vesicle clusters from both Alnus and Hippophae nodules showed no detectable activity of the glyoxylate cycle enzymes isocitrate lyase and malate synthase, suggesting the absence of a complete glycolysis in the endophyte.
Abstract: The occurrence and localization of enzymes involved in glycolysis, tricarboxylic acid cycle and glyoxylate cycle in root nodules of Alnus glutinosa (L.) Vill. and Hippophae rhamnoides L. ssp. rhamnoides were studied. The following enzymes, catalyzing reversible steps in the glycolysis, were found in both the endophyte Frankia spp. and the plant cytosol of Alnus nodules: fructose-1,6-diphosphate aldolase, glyceralde-hyde-3-phosphate dehydrogenase, phosphoglycerate kinase and enolase. The enzymes catalyzing irreversible steps in glycolysis, viz. hexokinase and pyruvate kinase, were detectable only in the plant cytosol. Similar results were obtained with nodule homogenates of Hippophae. This indicates the absence of a complete glycolysis in the endophyte. Vesicle clusters of the nodule endophyte of Alnus contained various dehydrogenases of the tricarboxylic acid cycle and showed activity of glutamate oxaloacetate transaminase. Respiration studies showed that vesicle clusters take up oxygen when supplied with NAD, glutamate and malate together. No oxygen uptake was found when any of these compounds was omitted. Vesicle clusters from both Alnus and Hippophae nodules showed no detectable activity of the glyoxylate cycle enzymes isocitrate lyase and malate synthase. Since these enzymes are known to be present in Frankia Avcll, when grown in a medium with Tween 80 as carbon source, it is suggested that the glyoxylate cycle enzymes are repressed in the root-nodule symbioses.
21 citations
TL;DR: Growth responses of Frankia isolates to decreasing water potential were monitored in systems where potentials were controlled by KCl, NaCl and Polyethylene glycol and the general pattern emerging was that isolates from Alnus glutinosa, A. viridis and Comptonia peregrina showed declining growth at potentials below −2 to −5 bar.
Abstract: Growth responses of Frankia isolates to decreasing water potential were monitored in systems where potentials were controlled by KCl, NaCl and Polyethylene glycol. The highest potential tested was −2 bar (basal medium). The general pattern emerging was that isolates fromAlnus glutinosa, A. viridis andComptonia peregrina showed declining growth at potentials below −2 to −5 bar. AMyrica gale isolate showed declining growth with decreasing potential. All isolates were more sensitive to decreases in potential in a matric controlled than an osmotic controlled system. They all showed approximately 50 percent growth reduction at −5 to −8 bar, and meagre growth at −16 bar after 35 days. The Comptonia isolate was the most vigorous at low potentials. Nitrogen fixation ability was monitored for two isolates. Highest specific activities were observed between −3 and −5 bar for the Myrica isolate and between −5 and −7.5 bar for theA. glutinosa isolate.
21 citations
TL;DR: It was investigated whether other Frankia strains behave similarly to Frankia AvcI1 regarding their nutritional demands and the ability of these actinomycetes to form root nodules on A lnus glutinosa.
Abstract: The isolation and in vitro cultivation of a Frankia sp. viz. Frankia CpI1, an actinomycete that gives rise to the formation of nitrogen-fixing root nodules on Comptonia peregrina was reported by Callaham et al. in 1978 [1]. Since that time a number of other Frankia strains has been isolated from root nodules of various non-leguminous plants, viz. Alnus glutinosa [2,3], Alnus rubra [4], Alnus viridis ssp. crispa [5,6], Myrica pennsylvanica [7], Elaeagnus umbellata [8,9], Casuarina equisetifolia [10], Hippopha~ sp. [11] and Shepherdia sp. [11]. Some research has been done in this laboratory on the Cand N-metabolism of Frankia AvcI 1, isolated from root nodules of Alnus viridis ssp. crispa [12-14]. It was shown that Frankia AvcI1 can utilize a number of fatty acids and the fatty acid residues of some Tweens as sole carbon source ([13], [12], respectively). No growth of Frankia AvcI 1 was observed on media containing glucose as sole carbon source, while the organism does not take up glucose from a medium containing both Tween-80 and glucose [12,14]. In the present contribution it was investigated whether other Frankia strains behave similarly to Frankia AvcI1 regarding their nutritional demands. Further investigations concerning some of the above-mentioned Frankia strains include the ability of these actinomycetes to form root nodules on A lnus glutinosa. Earlier it was shown [12] that Frankia AvcI1 cannot utilize succinate as sole carbon source. This phenomenon is due to the fact that no uptake of this compound occurs as shown in the present paper. Also some additional work has been done on the nitrogen metabolism of Frankia AvcI1. In earlier papers it was shown that free-living Frankia AvcI1 can utilize either NH~[13] or Casamino acids [12] as N-source. Glutamic acid and aspartic acid were found to be preferably taken up from a mixture of amino acids, whereas the concentrations of the other amino acids remained unchanged during the growth of the organism [12]. Some more details on the utilization of amino acids by Frankia AvcI1 are reported in the present work.
20 citations
TL;DR: Light and electron microscopic studies have established that the endophyte of root nodules of Discaria toumatou is an actinomycete resembling those of other Frankia-induced actinorhizal nodules, and both the hyphal and vesicular forms of theendophyte are surrounded by a polysaccharide capsule.
Abstract: Light and electron microscopic studies have established that the endophyte of root nodules of Discaria toumatou is an actinomycete resembling those of other Frankia-induced actinorhizal nodules. The prokaryotic micro-organism has septate hyphae of 0.4–0.7 µm diam., and forms spherical vesicles of approx. 4 µm diam. in the infected plant cells. These vesicles contain complete and incomplete septa, granulated regions, electrondense regions, and prominent nucleoids. No sporangia or spores were seen in the nodules. Both the hyphal and vesicular forms of the endophyte are surrounded by a polysaccharide capsule. The infected host cells contain a single, large, lobed nucleus, many large plastids and mitochondria, and a few microbodies.
13 citations
TL;DR: The twoPurshia species were similar in nodulation, nitrogen fixation and growth, although important exceptions exist that indicate species may differ in adaptability to certain soil conditions.
Abstract: Nitrogen fixing trees and shrubs may be useful in revegetation efforts. Speculation that insufficient endophyte populations in surface soils may limit non-leguminous symbiotic nitrogen fixation in marginal land was explored.Purshia tridentata andP. glandulosa seedlings were grown in greenhouse trials using ten soils from nativePurshia sites. Treatments include a control, an inoculated treatment, and six mmole nitrogen amendment. When inoculated with aP.tridentata crushed nodule inoculum, two of five non-nodulating soils and three sparsely nodulating soils produced well nodulated plants. Inoculation also increased nodule mass, total nitrogen, nitrogen content and shoot dry mass in plants from some of the soils. Of the three soils failing to produce nodulated plants when inoculated, one produced plants that responded well to nitrogen additions but failed to nodulate under low nitrogen conditions; another produced severely stunted plants indicating nutritional limitations on the host; and the third produced plants that were not nitrogen deficient. An application of nitrogen completely suppressed nodulation in all but one soil. The twoPurshia species were similar in nodulation, nitrogen fixation and growth, although important exceptions exist that indicate species may differ in adaptability to certain soil conditions.