Sensitivity of Rhizobium to selected isoflavonoids

1980 ◽  
Vol 26 (4) ◽  
pp. 542-545 ◽  
Author(s):  
C. E. Pankhurst ◽  
D. R. Biggs
Keyword(s):  
Effective Dose ◽  
Inhibitory Activity ◽  
Soft Agar ◽  
Biochanin A ◽  
Liquid Media ◽  
Fast Growing ◽  
Rhizobium Strains ◽  
Slow Growing

Eleven isoflavonoids were tested in both soft agar and liquid media for inhibitory activity against eight Rhizobium strains. Results of the two bioassays showed that pisatin, coumestrol, biochanin A, formononetin, genistein, rotenone, and vestitol lacked significant inhibitory activity. Phaseollin and maackiain were moderately inhibitory (ED50 (mean effective dose) = 30–100 μg/mL), and medicarpin and kievitone were strongly inhibitory (ED50 = 10–60 μg/mL) towards slow-growing R. japonicum and R. lupini and also towards two fast-growing Lotus rhizobia. In contrast, R. trifolii, R. leguminosarum, and R. phaseoli were not affected by these compounds (ED50 > 100 μg/mL), and R. meliloti was inhibited only by kievitone (ED50 = 30–60 μg/mL). At a concentration of 100 μg/mL, medicarpin and kievitone were found to be bactericidal to R. japonicum, R. lupini, and the fast-growing Lotus rhizobia.

Cholesterol is accumulated by mycobacteria but its degradation is limited to non-pathogenic fast-growing mycobacteria

2000 ◽  
Vol 46 (9) ◽  
pp. 826-831 ◽  
Author(s):  
Yossef Av-Gay ◽  
Rafat Sobouti
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Carbon Source ◽  
Sole Carbon Source ◽  
Mycobacterial Infection ◽  
Growth Media ◽  
Bacillus Calmette Guerin ◽  
Liquid Media ◽  
Fast Growing ◽  
Solid Media ◽  
Slow Growing

In this report we show that fast-growing non-pathogenic mycobacteria degrade cholesterol from liquid media, and are able to grow on cholesterol as a sole carbon source. In contrast, slow-growing mycobacteria, including pathogenic Mycobacterium tuberculosis and bacillus Calmette-Guérin (BCG), do not degrade and use cholesterol as a carbon source. Nevertheless, pathogenic mycobacteria are able to uptake, modify, and accumulate cholesterol from liquid growth media, and form a zone of clearance around a colony when plated on solid media containing cholesterol. These data suggest that cholesterol may have a role in mycobacterial infection other than its use as carbon source.Key words: mycobacteria, cholesterol, biodegradation.

scholarly journals Genotypic traits and tradeoffs of fast growth in silver birch, a pioneer tree

Oecologia ◽  
2021 ◽  
Author(s):  
Juha Mikola ◽  
Katariina Koikkalainen ◽  
Mira Rasehorn ◽  
Tarja Silfver ◽  
Ulla Paaso ◽  
...  
Keyword(s):  
Resource Competition ◽  
Leaf Growth ◽  
N Uptake ◽  
Insect Herbivory ◽  
Fast Growth ◽  
Grass Cover ◽  
Soil N ◽  
Fast Growing ◽  
Slow Growing ◽  
Leaf N

AbstractFast-growing and slow-growing plant species are suggested to show integrated economics spectrums and the tradeoffs of fast growth are predicted to emerge as susceptibility to herbivory and resource competition. We tested if these predictions also hold for fast-growing and slow-growing genotypes within a silver birch, Betula pendula population. We exposed cloned saplings of 17 genotypes with slow, medium or fast height growth to reduced insect herbivory, using an insecticide, and to increasing resource competition, using naturally varying field plot grass cover. We measured shoot and root growth, ectomycorrhizal (EM) fungal production using ergosterol analysis and soil N transfer to leaves using 15N-labelled pulse of NH4+. We found that fast-growing genotypes grew on average 78% faster, produced 56% and 16% more leaf mass and ergosterol, and showed 78% higher leaf N uptake than slow-growing genotypes. The insecticide decreased leaf damage by 83% and increased shoot growth, leaf growth and leaf N uptake by 38%, 52% and 76%, without differences between the responses of fast-growing and slow-growing genotypes, whereas root mass decreased with increasing grass cover. Shoot and leaf growth of fast-growing genotypes decreased and EM fungal production of slow-growing genotypes increased with increasing grass cover. Our results suggest that fast growth is genotypically associated with higher allocation to EM fungi, better soil N capture and greater leaf production, and that the tradeoff of fast growth is sensitivity to competition, but not to insect herbivory. EM fungi may have a dual role: to support growth of fast-growing genotypes under low grass competition and to maintain growth of slow-growing genotypes under intensifying competition.

scholarly journals Studies on the Regulation of Algal Growth by Gibberellin

1971 ◽  
Vol 24 (4) ◽  
pp. 1115 ◽  
Author(s):  
RC Jennings
Keyword(s):  
Red Algae ◽  
Algal Growth ◽  
Red Alga ◽  
General Phenomenon ◽  
Hypnea Musciformis ◽  
Fast Growing ◽  
High Concentrations ◽  
Amo 1618 ◽  
Slow Growing

CCC and Amo.1618, at relatively high concentrations only, inhibited the growth of excised branch apices of the red alga Hypnea musciformis. Neither GA3 nor GA7 stimulated growth of the alga in the presence or absence of these compounds, and gibberellin-like material extracted from H. musciformis also failed to stimulate growth. However, both gibberellins stimulated the growth of slow-growing, but not fast-growing, branch apices of the related red alga Gracilaria verucosa. It is concluded that endogenous gibberellins may not regulate the growth of H. musciformis, but this is likely to be a peculiarity of this species and not a general phenomenon in red algae.

SENSITIVITY AND ADAPTATION OF SELECTED RHIZOBIA AND AGROBACTERIA TO PARAQUAT

1985 ◽  
Vol 65 (3) ◽  
pp. 555-562 ◽  
Author(s):  
E. B. ROSLYCKY
Keyword(s):  
Key Words ◽  
Genetic Effect ◽  
Agrobacterium Radiobacter ◽  
Plant Weight ◽  
Fast Growing ◽  
Plant Symbiont ◽  
Paraquat Resistance ◽  
Rhizobium Lupini ◽  
The Relationship ◽  
Slow Growing

Sensitivity to paraquat as function of growth varied considerably among 15 rhizobia from seven cross-inoculation groups and 13 agrobacteria from five different species. No relationship was evident between the sensitivity and the "fast-growing" or the "slow-growing" characteristics among the rhizobia. The agrobacteria were uniformly less sensitive. Maximum stabilized paraquat resistance induced by the adptations ranged from 200 μg paraquat∙mL−1 in Rhizobium lupini 112, to 20 000 μg paraquat∙mL−1 in Agrobacterium radiobacter R-590 and A. tumefaciens A6-K1. No relationship was found between the sensitivity and the adaptability. Identical lytic patterns with six bacteriophages confirmed the relationship between the adapted and parent cultures suggesting no genetic effect of paraquat on susceptibility to lysis. The bacteria-plant symbiont interaction, including nodulation, plant weight, vigor and color, was unaffected by the adaptations to paraquat resistance. Similarly, the adaptations exerted no effect on tumorigenicity of A. tumefaciens A6-K1. Key words: Rhizobia, agrobacteria, adaptation, herbicides, paraquat, N2-fixation

scholarly journals Current state of Donetsk dendroflora

2016 ◽  
Vol 5 (2) ◽  
pp. 20-24
Author(s):  
Alexandr Zakharovych Glukhov ◽  
Lyudmila Valerievna Kharkhota ◽  
Georgy Alexandrovych Pasternak ◽  
Elena Nikolaevna Likhatskaya
Keyword(s):  
Age Structure ◽  
Steppe Zone ◽  
Age Group ◽  
Fast Growing ◽  
Industrial City ◽  
Current State ◽  
Study Results ◽  
Slow Growing ◽  
Trees And Shrubs ◽  
Fast Growing Species

We present the study results of modern dendroflora of Donetsk (a large industrial city of the south steppe zone). We have determined the species composition, analyzed the age structure of plantations, estimated the life condition of trees and shrubs. Plantations compose 76 species and 32 forms, types, sorts of trees, including 11 species and 9 sorts of the coniferous, as well as 79 species and 35 forms, sorts of shrubs, including 7 species and 19 sorts of the coniferous. Trees and shrubs belong to 78 genera, which are included into 38 families. The most represented family among the deciduous is Rosaceae Juss. - 46 species and 13 sorts, among the coniferous - Pinaceae Lindl. (9 species and 6 sorts), Cupressaceae Rich. ex Bartl. (7 species and 22 sorts). Tree species dominating in plantations are Populus bolleana Lauche (14,6% of the total number of trees), dominating shrubs are the sorts of Rosa hybrida (44,0% of the total number of shrubs). In the plantations studied we have indicated 33 species of trees and shrubs of the aboriginal fraction of local flora. Analysis of the age structure of plantations revealed that the majority of trees compose the age group of 20-29 years, the majority of shrubs - up to 10 years. Fast-growing species prevail in plantations (73% of the total number). Viability of the most part of trees of fast-growing and slow-growing species is estimated by 4 points, viability of moderate-growing species - by 6 points. The number of trees being in unsatisfactory condition (0 or 1-3 points) prevails among fast-growing species.

Variation of Taxane Content in Needles of Taxus x media Cultivars with Different Growth Characteristics

2006 ◽  
Vol 61 (9-10) ◽  
pp. 619-624 ◽  
Author(s):  
Xinkun Wang ◽  
Yinghua Huang ◽  
Andrew J. Mort ◽  
Yuhong Zeng ◽  
Charles G. Tauer ◽  
...  
Keyword(s):  
High Performance ◽  
Biomass Accumulation ◽  
Dry Weight ◽  
Growth Characteristics ◽  
Alternative Methods ◽  
Baccatin Iii ◽  
Fast Growing ◽  
Taxus X Media ◽  
Slow Growing ◽  
Group 1

AbstractNeedles from 17 different Taxus x media cultivars, belonging to 4 groups showing different growth characteristics, were analyzed using high performance liquid chromatography for their content of 10-deacetylbaccatin III, baccatin III, cephalomannine and paclitaxel (Taxol®). The 4 Taxus x media cultivar groups were: 1.) medium to fast growing and upright form; 2.) slow growing and upright form; 3.) fast growing and spreading form; and 4.) slow growing and spreading form. The purpose of this study was to identify yew cultivars of fast growth rate, upright growth and high taxane content in their needles. The highest content of paclitaxel was found in ‘Coleana’ of group 1 (378 μg/g of the extracted dry weight). Three cultivars in group 1, ‘Coleana’, ‘Stovekenii’ and ‘Hicksii’, make good candidates for taxane extraction because of their high paclitaxel and 10-deacetylbaccatin III content, fast biomass accumulation and upright growing form. They are also good starting materials to develop alternative methods for the production of paclitaxel and its analogous compounds through modern biotechnology approaches.

scholarly journals Effects of Initial Soil Properties on Three-Year Performance of Six Tree Species in Tropical Dry Forest Restoration Plantings

Forests ◽  
2019 ◽  
Vol 10 (5) ◽  
pp. 428 ◽  
Author(s):  
Valentina Carrasco-Carballido ◽  
Cristina Martínez-Garza ◽  
Héctor Jiménez-Hernández ◽  
Flavio Márquez-Torres ◽  
Julio Campo
Keyword(s):  
Soil Properties ◽  
Growth Rates ◽  
Tropical Dry Forest ◽  
Dry Forest ◽  
Diameter Growth ◽  
Relative Growth ◽  
Fast Growing ◽  
Initial Soil ◽  
Slow Growing ◽  
Fast Growing Species

Deforestation of tropical dry forest reduces soil fertility, with negative effects on future restoration intervention. To evaluate the effect of initial soil properties on three-year performance of six tree species in restoration settings, we measured C, N, and P contents in topsoils of 48 plots under minimal (exclusions of livestock grazing) and maximal (plantings of six native species) restoration intervention during two years in tropical dry forest in central Mexico. Survival and height and diameter relative growth rates were evaluated by species and by growth rank (three fast- and three slow-growing species). After two years, organic C and the C:N ratio increased early during natural succession; these increases might be related to high density of N2-fixing recruits at both intervention levels. Changes in N availability for plants (i.e., NO3− and NH4+ contents) occurred after cattle exclusion. After 40 months, the fast-growing legume Leucaena esculenta (DC.) Benth. had the highest survival (65.55%) and relative growth rate in both height (3.16%) and diameter (5.67%). Fast-growing species had higher survival and diameter growth rates than slow-growing species. Higher diameter growth rates for fast-growing species may be associated with a higher ability to forage for soil resources, whereas similar height growth rates for slow and fast-growing species suggested low competition for light due to slow natural succession at the site. Planted seedlings had higher survival possibly due to initial high NO3− content in the soil. Also, fast-growing species seem to benefit from initially higher pH in the soil. Both soil properties (i.e., pH and NO3−) may be augmented to favor the performance of fast-growing species in restoration plantings and to further accelerate soil recovery in tropical dry forests.

scholarly journals Differences in growth-economics of fast vs. slow growing grass species in response to temperature and nitrogen limitation individually, and in combination

BMC Ecology ◽  
2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Claudia Colesie ◽  
Zsofia Reka Stangl ◽  
Vaughan Hurry
Keyword(s):  
Nutrient Availability ◽  
Nitrogen Availability ◽  
Global Environmental Change ◽  
Performance Outcomes ◽  
Plant Performance ◽  
Grass Species ◽  
Growth Responses ◽  
Fast Growing ◽  
Environment Temperature ◽  
Slow Growing

Abstract Background Fast growing invasive alien species are highly efficient with little investment in their tissues. They often outcompete slower growing species with severe consequences for diversity and community composition. The plant economics trait-based approach provides a theoretical framework, allowing the classification of plants with different performance characteristics. However, in multifaceted background, this approach needs testing. The evaluation and prediction of plant performance outcomes in ecologically relevant settings is among the most pressing topics to understand and predict ecosystem functioning, especially in a quickly changing environment. Temperature and nutrient availability are major components of the global environmental change and this study examines the response of growth economic traits, photosynthesis and respiration to such changes for an invasive fast-growing (Bromus hordaceus) and a slow-growing perennial (Bromus erectus) grass species. Results The fully controlled growth chamber experiment simulated temperature—and changes in nitrogen availability individually and in combination. We therefore provide maximum control and monitoring of growth responses allowing general growth trait response patterns to be tested. Under optimal nitrogen availability the slow growing B. erectus was better able to handle the lower temperatures (7 °C) whilst both species had problems at higher temperatures (30 °C). Stresses produced by a combination of heat and nutrient availability were identified to be less limiting for the slow growing species but the combination of chilling with low nutrient availability was most detrimental to both species. Conclusions For the fast-growing invader B. hordeaceus a reduction of nitrogen availability in combination with a temperature increase, leads to limited growth performance in comparison to the slow-growing perennial species B.erectus and this may explain why nutrient-rich habitats often experience more invasion than resource-poor habitats.

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