Morphological, physiological and metabolic comparisons between runner-like and sheet-like inbred lines of a colonial hydroid.

1998 ◽  
Vol 201 (20) ◽  
pp. 2821-2831 ◽  
Author(s):  
NW Blackstone
Keyword(s):  
Inbred Line ◽  
Redox State ◽  
Inbred Lines ◽  
Colony Morphology ◽  
Colony Development ◽  
Metabolic Capacity ◽  
Stolon Development ◽  
Morphological Differences ◽  
Induced Changes ◽  
Colonial Hydroid

Hydractiniid hydroids display a range of morphological variation from sheet-like forms (i.e. closely spaced polyps with high rates of stolon branching) to runner-like forms (i.e. widely spaced polyps with low rates of stolon branching), thus exemplifying the patterns of heterochrony found in many colonial animals. A sheet-like and a runner-like inbred line of Podocoryne carnea were produced to investigate this heterochronic variation further. Selection on colony morphology at the time of the initiation of medusa production resulted in dramatic differences by the F5 and F6 generations. Compared with colonies of the sheet-like inbred line, runner-like colonies exhibited smaller sizes at the initiation of medusa production, more irregular colony shapes and diminished stolon development relative to polyp development. In addition to these differences in colony morphology, runner-like colonies also exhibited larger medusae and a greater amount of gastrovascular flow to the peripheral stolons. To assess differences in the metabolic capacity underlying this variaton in flow, the redox state of the polyp epitheliomuscular cells was measured using the fluorescence of NAD(P)H. In response to feeding-induced changes in gastrovascular flow, runner-like colonies show greater redox variation than sheet-like ones, plausibly corresponding to the greater amounts of flow generated by the former colonies relative to the latter. Perturbing the system with dilute solutions of 2,4-dinitrophenol similarly indicates that runner-like colonies contain more functionally oxidizable NAD(P)H. The correlation between gastrovascular flow and morphological differences supports the hypothesis that the former mediates the timing of colony development, perhaps in concert with the observed variation in the redox state of polyp epitheliomuscular cells.

The ffs Allele Conditions Flower Stem Fasciation in Red Beet

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 527f-528
Author(s):  
I.L. Goldman
Keyword(s):  
Genetic Control ◽  
Inbred Line ◽  
Goodness Of Fit ◽  
Female Parent ◽  
Inbred Lines ◽  
Chi Square ◽  
Recessive Character ◽  
Variable Expression ◽  
Red Beet ◽  
Flower Stem

A fasciated flower stem character arose spontaneously during development of the red beet (Beta vulgaris L.) inbred line W411. The fasciated character is manifest by a flattened flower stem with petioles coalesced into a twisted, ribbonlike appearance. No fasciation is present in the vegetative stem or petioles. An inheritance study was conducted to determine the genetic control of flower stem fasciation. The inbred line W411 was used both as a male and female parent in crosses with four red beet inbred lines. Segregating progenies in both the BC1 and F2 generations were developed and scored for the fasciated flower stem character. Variable expression of the fasciated flower stem phenotype was observed in these progenies; however, the presence of flattened flower stems at the stem/hypocotyl junction was unequivocal. Chi-square goodness-of-fit tests in both the BC1 and F2 generations did not deviate significantly from expected ratios for a monogenic recessive character for each genetic background. No reciprocal differences were detected for any cross in this group of four inbred lines, which suggests the lack of maternal effect for the fasciated character. The symbol ffs is proposed to describe the genetic control of the fasciated flower stem phenotype.

scholarly journals Inbreeding and thermal adaptation in Drosophila subobscura

Genome ◽  
2014 ◽  
Vol 57 (9) ◽  
pp. 481-488 ◽  
Author(s):  
Goran Zivanovic ◽  
Conxita Arenas ◽  
Francesc Mestres
Keyword(s):  
Inbred Line ◽  
Thermal Adaptation ◽  
Inbred Lines ◽  
Light Period ◽  
Drosophila Subobscura ◽  
Adaptive Potential ◽  
Line Number ◽  
Evolutionary Forces ◽  
Laboratory Conditions ◽  
Significant Line

Using a well-adapted Drosophila subobscura population (Avala, Serbia), a drastic experiment of inbreeding was carried out to assess whether the expected level of homozygosity could be reached or if other evolutionary forces affected the process. In general, no significant changes of inversion (or arrangement) frequencies were detected after 12 brother–sister mating generations. Furthermore, no significant differences were obtained between observed and expected (under the inbreeding model) karyotypic frequencies. Thus, these results seemed to indicate that the main evolutionary factor in the experiment was inbreeding. However, in the G12 generation, complete chromosomal fixation was reached only in two out of the eight final inbred lines. In these lines, the chromosomal compositions were difficult to interpret, but they could be likely a consequence of adaptation to particular laboratory conditions (constant 18 °C, food, light period, etc.). Finally, in a second experiment, the inbred lines presented higher fertility at 18 °C than at 13 °C. Also, there was a significant line effect on fertility: inbred line number 6 (A1, J1, U1+2; U1+2+6, E8, and O3+4+7) presented the highest values, which maybe the result of an adaptation to laboratory conditions. Thus, the results obtained in our experiments reflect the adaptive potential of D. subobscura inversions.

scholarly journals Stability Assessment of Single-Cross Maize Hybrids Using GGE-Biplot Analysis

2021 ◽  
Vol 13 (2) ◽  
pp. 78
Author(s):  
L. Musundire ◽  
J. Derera ◽  
S. Dari ◽  
A. Lagat ◽  
P. Tongoona
Keyword(s):  
Grain Yield ◽  
South African ◽  
Inbred Line ◽  
Inbred Lines ◽  
Yield Potential ◽  
Research Station ◽  
Gge Biplot ◽  
Single Cross ◽  
Ideal Genotype ◽  
Single Cross Hybrids

Grain yield potential of new maize hybrid varieties across target environments contributes to the uptake of these varieties by farmers. Evaluation of single-cross hybrids developed from test crossing introgressed inbred lines bred for three distinct environments to elite tropical inbred line testers was carried out. The study’s objective was to assess grain yield stability and genotype adaptability of the single-cross hybrids across South African environments relative to adapted commercial hybrid checks. One hundred and twenty-two introgressed inbred lines developed using the pedigree breeding program were crossed to four tropical elite inbred line testers using line × tester mating design to obtain 488 experimental single cross hybrids. Subject to availability of adequate seed for evaluation, a panel of 444 experimental single-cross hybrids was evaluated using an augmented design in two experiments defined as Population A and B for the study’s convenience in South African environments. Data for grain yield (t/ha) performance for experimental single-cross hybrids and commercial check hybrids in Population A and B across environments and individual environments identified experimental single-cross hybrids that had significant comparable grain yield (t/ha) performance relative to best commercial check hybrid (PAN6Q445B) on the market. The selected experimental single-cross hybrids 225, 89, 246 and 43 (Population A) and 112 (Population B) also had a better average rank position for grain yield (t/ha) relative to best commercial check hybrid. These selected experimental single-cross hybrids had a grain yield (t/ha) advantage range of 0.9-6.7% for Population A and 7.3% for Population A and B, respectively, relative to the adapted commercial check hybrid. GGE biplot patterns for which won-where for Population A indicated that at Potchefstroom Research Station and Ukulinga Research Station experimental single-cross hybrids 127 and135 were the vertex (winning) hybrids. Cedera Research Station did not have a vertex hybrid for Population A. For Population B, experimental single-cross hybrids 112, 117 and 18 were the vertex hybrids at Cedera Research Station, Ukulinga Research Station and Potchefstroom Research Station, respectively. Experimental single-cross hybrid 257 was identified as ideal genotype for Population A, while experimental single-cross hybrid 121 in Population B was the ideal genotype. Ideal environments were also identified as Ukulinga Research Station for Population A, and Cedera Research Station for Population B. Average-environment coordination (AEC) view of the GGE biplot in Population A indicated that experimental single-cross hybrids 1 was highly stable across environments. In comparison, Population B experimental single-cross hybrid 161 was highly stable across environments. In conclusion, selected single-cross hybrids in the current study can also be advanced for further evaluation with a possibility for identifying high yielding and stable single-cross hybrids for variety registration and release in target environments in South Africa.

Mapping of capillary flow, cellular redox state, and resting membrane potential in hypoperfused rat myocardium

1999 ◽  
Vol 277 (5) ◽  
pp. H2050-H2064 ◽  
Author(s):  
Frank Brasch ◽  
Marion Neckel ◽  
Rolf Volkmann ◽  
Gerhard Schmidt ◽  
Gerhard Hellige ◽  
...  
Keyword(s):  
Membrane Potential ◽  
Trypan Blue ◽  
Redox State ◽  
Capillary Flow ◽  
Resting Membrane Potential ◽  
Capillary Perfusion ◽  
Cellular Redox ◽  
Nadh Fluorescence ◽  
Induced Changes ◽  
Tetramethylrhodamine Methyl Ester

The influence on myocyte viability of ischemia-induced changes in capillary perfusion was studied in the hearts of anesthetized rats subjected to partial occlusion of the left coronary artery for 45 min. Timed plasma labeling was applied to determine perfusion patterns. Changes in the fluorescence of preloaded potential-sensitive dyes [tetramethylrhodamine methyl ester (TMRM) and bis-oxonol], of trypan blue, and of endogeneous NADH were utilized in characterizing myocyte viability in histological sections of the heart. Within the hypoperfused zone, localized areas appeared vascularly nonlabeled for periods of at least 10 min. Within these areas a reduction in TMRM fluorescence occurred in 82.5% of the tissue, signaling a reduced resting membrane potential. In the same areas 37.7% of the myocytes revealed an NADH fluorescence lower than that regularly found in anoxic tissues. This correlated with an especially low level of TMRM, with increased fluorescence bis-oxonol and with an accumulation of trypan blue. In conclusion, in localized hypoperfusion-induced zones lacking capillary flow, an inhomogeneous pattern of reductions in myocyte viability develops, which appears to be relevant in ischemia-induced arrhythmias.

scholarly journals Exercise-training-induced changes in metabolic capacity with age: the role of central cardiovascular plasticity

AGE ◽  
2013 ◽  
Vol 36 (2) ◽  
pp. 665-676 ◽  
Author(s):  
Eivind Wang ◽  
Morten Svendsen Næss ◽  
Jan Hoff ◽  
Tobias Lie Albert ◽  
Quan Pham ◽  
...  
Keyword(s):  
Exercise Training ◽  
Metabolic Capacity ◽  
Induced Changes

scholarly journals Evaluation of CIMMYT maize (Zea mays L.) germplasm by tropical inbred testers

2015 ◽  
Vol 43 (2) ◽  
pp. 131-139
Author(s):  
Uttam Chandel ◽  
BS Mankotia ◽  
KS Thakur
Keyword(s):  
Zea Mays ◽  
Inbred Line ◽  
Zea Mays L ◽  
Inbred Lines ◽  
Environment Interaction ◽  
Tropical Maize ◽  
Selected Lines ◽  
Heterotic Groups

Twenty five CIMMYT inbreds were crossed with four elite tropical maize testers. Results exhibited that one inbred line tester can select the top best lines from a large number of CIMMYT lines and two testers gave more reliable results than one tester did. However, when line × environment interaction was significant, selected lines by one tester in one environment were not necessarily same as those selected at another environment indicating thereby that different testers should be used for selecting best inbreds at different environments. This study also showed that inbred lines from different maize heterotic groups did not show any significant differences in identifying best CIMMYT germplasm DOI: http://dx.doi.org/10.3329/bjb.v43i2.21661 Bangladesh J. Bot. 43(2): 131-139, 2014 (September)

scholarly journals Change in root apical protein and peroxidase activity in response to aluminum in tolerant and sensitive maize inbred lines

2002 ◽  
Vol 14 (3) ◽  
pp. 219-224 ◽  
Author(s):  
Isabel Regina Prazeres de Souza ◽  
Vera Maria Carvalho Alves ◽  
Sidney Netto Parentoni ◽  
Antônio Carlos de Oliveira ◽  
Flávia França Teixeira ◽  
...  
Keyword(s):  
Protein Content ◽  
Inbred Line ◽  
Peroxidase Activity ◽  
Total Protein ◽  
Primary Root ◽  
Inbred Lines ◽  
Total Protein Content ◽  
Anionic Peroxidase ◽  
Sensitive Line ◽  
Peroxidase Isoforms

The effects of a short-term (80 min) exposure to 222 µM aluminum (Al) on the protein content and expression and on peroxidase activity and isoenzymes in the primary root of maize were evaluated. Two inbred lines differing in their level of tolerance to Al were used: Cateto 237 (tolerant) and L36 (sensitive). The apical 20 mm of the primary root was divided into 2-mm-long segments that were analyzed for total protein content and peroxidase activity. These results demonstrate that the total protein content along the root apex was not affected by Al in the tolerant inbred line, but decreased in the sensitive line. In the apical 2 mm of the root of the sensitive line, the expression of low molecular weight proteins (43 kDa or smaller) was decreased. Expression of low molecular proteins increased in the tolerant inbred line, even though total protein content did not increase. This suggests that some of these proteins could play a role in metal tolerance, perhaps as binding peptides. While the peroxidase activity of the tolerant inbred line did not change with exposure to Al, peroxidase activity in the apical 6 mm of the root of the sensitive line decreased. The tolerant inbred line constitutively expressed more anionic peroxidase isoforms. These results demonstrate that maintenance of protein expression may be an important component of the plant's resistance to Al stress, and that resistance to Al stress is associated with the higher expression of anionic peroxidase isoforms.

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