Structural and physiological bases for effectivity of soybean nodules formed by fast-growing and slow-growing bacteria

1988 ◽  
Vol 66 (3) ◽  
pp. 526-534 ◽  
Author(s):  
J. Lin ◽  
K. B. Walsh ◽  
D. T. Canvin ◽  
D. B. Layzell
Keyword(s):  
Infected Cell ◽  
Central Zone ◽  
Dry Weight ◽  
Fast Growing ◽  
Infected Cells ◽  
Nitrogenase Activities ◽  
Total Dry Weight ◽  
Slow Growing ◽  
Fast Growing Rhizobia ◽  
Crosssectional Area

Five weeks after planting, the total dry weight of the association between the soybean cultivar Maple Arrow and the slow-growing rhizobia, Bradyrhizobium japonicum USDA 16, was 1.6 times that with the fast-growing rhizobia, Rhizobium fredii QB1130. In contrast, with the uncultivated variety, 'Peking', the USDA 16 association possessed only 0.58 of the dry weight of the QB1130 association. These growth characteristics could not be fully explained in terms of number or mass of nodules formed. Rather, the specific nodule activity (rate of H2 evolution in Ar–O2 per unit nodule mass) was lower in the poorly effective symbioses ('Maple Arrow' × QB1130; 'Peking' × USDA 16). Nodules of the less effective symbioses were characterized by large deposits of starch in the cortex and in uninfected cells of the central zone, a thick cortical zone, relatively less infected cell area in the central zone, and fewer bacteria per unit crosssectional area of infected cell. Therefore, there were fewer bacteria per nodule in these symbioses. When total nitrogenase activities were expressed per bacteroid number or per bacteroid volume, no significant differences were observed among the four symbioses. These results indicate that the poor effectivity of the 'Maple Arrow' × QB1130 and 'Peking' × USDA 16 symbioses was due to a limitation of either bacterial release from the infection thread or bacterial proliferation within the infected cells.

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.

A succinate transport mutant of Bradyrhizobium japonicum forms ineffective nodules on soybeans

1992 ◽  
Vol 38 (3) ◽  
pp. 230-234 ◽  
Author(s):  
Abdel Kader Yousef Gamal El-Din
Keyword(s):  
Bradyrhizobium Japonicum ◽  
Symbiotic Nitrogen Fixation ◽  
Morphological Changes ◽  
Dicarboxylic Acids ◽  
Starch Granules ◽  
Fast Growing ◽  
Dicarboxylate Transport ◽  
Transport Mutants ◽  
Infected Cells ◽  
Slow Growing

Biochemical evidence has shown that dicarboxylic acids actively support symbiotic nitrogen fixation by both fast- and slow-growing Rhizobium. Mutants defective in the active uptake of succinate have been previously described only in species of the fast-growing rhizobium. This article is a report on the isolation of mutants defective in dicarboxylate transport in a slow-growing species of rhizobium, Bradyrhizobium japonicum. One of these presumptive dicarboxylate transport mutants, GTS, was characterized further. Cultured GTS was unable to accumulate [14C]succinate above background levels but possessed normal rates of malate dehydrogenase, fumarase, and hydroxybutyrate dehydrogenase activities. When inoculated onto soybeans, GTS produced a Nod+, Fix− phenotype. The bacteroids isolated from these nodules failed to accumulate labelled succinate. Electron micrographs of nodules formed by inoculation with GTS appeared normal with the exceptions of more prominent peribacteroid spaces in the infected cells and the appearance of starch granules in the noninfected cells. The phenotypical and morphological changes observed for B. japonicum are similar to those previously reported for the fast-growing species. Key words: Fix−, mutant, Rhizobium, succinate, transport.

Fast- and slow-growing rhizobia: differences in sucrose utilization and invertase activity

1974 ◽  
Vol 20 (4) ◽  
pp. 605-609 ◽  
Author(s):  
G. Martinez-de Drets ◽  
A. Arias ◽  
M. Rovira de Cutinella
Keyword(s):  
Invertase Activity ◽  
Sucrose Phosphorylase ◽  
Fast Growing ◽  
New Evidence ◽  
Slow Growing ◽  
Fast Growing Rhizobia ◽  
Sucrose Utilization

Growth on sucrose by 64 strains of Rhizobium was determined, and differences in the use of this disaccharide by rhizobia were established. An inducible invertase was detected in strains of the fast-growing group of Rhizobium but neither invertase nor a sucrose phosphorylase was found in strains of the slow-growing group of Rhizobium.A new evidence to consolidate enzymatically slow-growing rhizobia in a different group from the fast-growing rhizobia is presented here.

Further Observations on the Virus of Epizootic Diarrhea of Infant Mice. An Electron Microscopic Study

1967 ◽  
Vol 25 ◽  
pp. 110-111
Author(s):  
W. G. Banfield ◽  
G. Kasnic ◽  
J. H. Blackwell
Keyword(s):  
Electron Microscope ◽  
Infected Cell ◽  
Microscopic Study ◽  
Intestinal Epithelium ◽  
Ultrastructural Study ◽  
Osmium Tetroxide ◽  
Lead Citrate ◽  
Electron Microscopic ◽  
Virus Particles ◽  
Infected Cells

An ultrastructural study of the intestinal epithelium of mice infected with the agent of epizootic diarrhea of infant mice (EDIM virus) was first performed by Adams and Kraft. We have extended their observations and have found developmental forms of the virus and associated structures not reported by them.Three-day-old NLM strain mice were infected with EDIM virus and killed 48 to 168 hours later. Specimens of bowel were fixed in glutaraldehyde, post fixed in osmium tetroxide and embedded in epon. Sections were stained with uranyl magnesium acetate followed by lead citrate and examined in an updated RCA EMU-3F electron microscope.The cells containing virus particles (infected) are at the tips of the villi and occur throughout the intestine from duodenum through colon. All developmental forms of the virus are present from 48 to 168 hours after infection. Figure 1 is of cells without virus particles and figure 2 is of an infected cell. The nucleus and cytoplasm of the infected cells appear clearer than the cells without virus particles.

BIOASSAY OF PROLACTIN

1969 ◽  
Vol 60 (1) ◽  
pp. 91-100 ◽  
Author(s):  
Charles S. Nicoll
Keyword(s):  
Epithelial Cells ◽  
Lipid Content ◽  
Dry Weight ◽  
Fat Content ◽  
Assay Sensitivity ◽  
Mucosal Epithelium ◽  
Wet Weight ◽  
Total Dry Weight

ABSTRACT The response of the pigeon crop-sac to systemically acting prolactin (injected subcutaneously) was evaluated by measuring the wet weight of the responsive lateral lobes of the organ and by determining the dry weight of a 4 cm diameter disc of mucosal epithelium taken from one hemicrop. Of several different injection schedules tested, administration of prolactin in four daily injections was found to yield optimal responses. When compared with a graded series of prolactin doses, measurement of the mucosal dry weight proved to be a better method of response quantification than determination of the crop-sac wet weight with respect to both assay sensitivity and precision. The submucosal tissue of the crop-sac was estimated to constitute about 64 % of the total dry weight of the unstimulated organ and it was found to be relatively unresponsive to prolactin stimulation in comparison with the mucosa. The lipid content of the mucosal epithelium was determined using unstimulated crop-sacs or tissues which showed varying degrees of prolactin-induced proliferation. The fat content of the mucosal epithelial cells increased only slightly more rapidly than the dry weight or the defatted dry weight of the mucosa. Suggestions are made for the further improvement of the systemic crop-sac assay for prolactin.

Impact of an Open Trellis on Canopy Growth, Light Interception, Yield, and Leaf Physiology of Red Raspberry (Rubus idaeus)

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 468b-468
Author(s):  
Stephen F. Klauer ◽  
J. Scott Cameron ◽  
Chuhe Chen
Keyword(s):  
Leaf Area ◽  
Total Nitrogen ◽  
Dry Weight ◽  
Light Interception ◽  
Rubus Idaeus ◽  
Above Ground Biomass ◽  
Red Raspberry ◽  
Leaf Physiology ◽  
Total Dry Weight ◽  
Upper Third

After promising results were obtained with an open-style split trellis (two top wires) in its initial year, two new trials were established in 1997 in northwest (Lynden) and southwest (Woodland) Washington. For the split trellis, actual yields were 33% (machine-picked 1/2 season) and 17% (hand-picked) greater, respectively, for the two locations compared to the conventional trellis (one top wire). In Woodland, canes from the split trellis had 33% more berries, 55% more laterals, 69% more leaves, and 25% greater leaf area compared with the conventional trellis. Greatest enhancement of these components was in the upper third of the canopy. Laterals were also shorter in this area of the split canopy, but there was no difference in average total length of lateral/cane between trellis types. Total dry weight/cane was 22% greater in the split trellis, but component partitioning/cane was consistent between the two systems with fruit + laterals (43%) having the greatest above-ground biomass, followed by the stem (30% to 33%) and the leaves (21% to 22%). Measurement of canopy width, circumference, and light interception showed that the split-trellis canopy filled in more quickly, and was larger from preanthesis through postharvest. Light interception near the top of the split canopy was 30% greater 1 month before harvest with 98% interception near the top and middle of that canopy. There was no difference between the trellis types in leaf CO2 assimilation, spectra, or fluorescence through the fruiting season, or in total nitrogen of postharvest primocane leaves.

scholarly journals Impact of Different Water Management Regimes on the Growth, Productivity, and Resource Use Efficiency of Dry Direct Seeded Rice in Central Punjab-Pakistan

Agronomy ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1151
Author(s):  
Sadam Hussain ◽  
Saddam Hussain ◽  
Zubair Aslam ◽  
Muhammad Rafiq ◽  
Adeel Abbas ◽  
...  
Keyword(s):  
Grain Yield ◽  
Hybrid Rice ◽  
Water Productivity ◽  
Dry Weight ◽  
Cost Ratio ◽  
Yield Attributes ◽  
Benefit Cost Ratio ◽  
Direct Seeded ◽  
Total Dry Weight ◽  
Benefit Cost

Dry direct-seeded rice has been shown to save irrigation water and labor. Nonetheless, irrigation management in dry direct-seeded rice has received very little attention. Here, we examined the potential of different irrigation regimes: aerobic rice (AR), alternate wetting and drying (AWD) and continuous flooding (CF) in dry direct-seeded rice cultivation on two rice cultivars (Pride-1 (hybrid indica) and NB-1 (inbred indica)). Growth, yield attributes, grain yield, total water input, water productivity and benefit cost ratio were measured. Our results showed that AR saved 11.22 and 28.40%, and 5.72 and 32.98% water compared with AWD and CF during 2018 and 2020, respectively. There was a significant difference in grain yield among treatments and cultivars. AWD and CF produced statistically same total dry weight and grain yield, while AR reduced the total dry weight by 31.34% and 38.04% and grain yield by 34.82% and 38.16% in comparison to AWD and CF, respectively, across the years. Except for 1000-grain weight and harvest index in AWD and CF, further differences in total dry weight and grain yield among irrigation treatments were primarily correlated with variations in yield attributes. Among the cultivars, hybrid rice performed better than inbred rice. Over the two-year period, hybrid rice increased total dry weight, grain yield, and water productivity by 9.28%, 13.05%, and 14.28%, respectively, as compared to inbred rice. Regarding water productivity (WP), the maximum percentage (40.90 and 26.53%) was recorded for AWD compared to AR and CF. Among cultivars, more water productivity (14.28%) was calculated for hybrid rice than inbred one. Chlorophyll and carotenoid contents, leaf area index and crop growth rate contributed to higher grain yield of hybrid rice under AWD and CF. In contrast to WP, the maximum benefit cost ratio was estimated to be higher for CF than that of AR and AWD. For the cultivars, the maximum value (2.26 in 2018 and 2.32 in 2020) was calculated for hybrid rice compared with the inbred one. In conclusion, these results suggests that AWD with maximum WP and CF with maximum BCR could be more efficient approaches than AR. Under CF, hybrid rice cultivars with higher yield and yield-related attributes, WP and BCR performed better.

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.

Effects of Temperature and CO2Concentration on the Growth of Cotton (Gossypium hirsutum), Spurred Anoda (Anoda cristata), and Velvetleaf (Abutilon theophrasti)

Weed Science ◽  
1988 ◽  
Vol 36 (6) ◽  
pp. 751-757 ◽  
Author(s):  
David T. Patterson ◽  
Maxine T. Highsmith ◽  
Elizabeth P. Flint
Keyword(s):  
Dry Matter ◽  
Dry Weight ◽  
Net Assimilation Rate ◽  
Assimilation Rate ◽  
Short Term ◽  
Leaf Weight ◽  
Matter Production ◽  
Total Plant ◽  
Net Assimilation ◽  
Total Dry Weight

Cotton, spurred anoda, and velvetleaf were grown in controlled-environment chambers at day/night temperatures of 32/23 or 26/17 C and CO2concentrations of 350 or 700 ppm. After 5 weeks, CO2enrichment to 700 ppm increased dry matter accumulation by 38, 26, and 29% in cotton, spurred anoda, and velvetleaf, respectively, at 26/17 C and by 61, 41, and 29% at 32/23 C. Increases in leaf weight accounted for over 80% of the increase in total plant weight in cotton and spurred anoda in both temperature regimes. Leaf area was not increased by CO2enrichment. The observed increases in dry matter production with CO2enrichment were caused by increased net assimilation rate. In a second experiment, plants were grown at 350 ppm CO2and 29/23 C day/night for 17 days before exposure to 700 ppm CO2at 26/17 C for 1 week. Short-term exposure to high CO2significantly increased net assimilation rate, dry matter production, total dry weight, leaf dry weight, and specific leaf weight in comparison with plants maintained at 350 ppm CO2at 26/17 C. Increases in leaf weight in response to short-term CO2enrichment accounted for 100, 87, and 68% of the observed increase in total plant dry weight of cotton, spurred anoda, and velvetleaf, respectively. Comparisons among the species showed that CO2enrichment decreased the weed/crop ratio for total dry weight, possibly indicating a potential competitive advantage for cotton under elevated CO2, even at suboptimum temperatures.

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.

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