scholarly journals Gamma rays induced morphological, flowering and palynological modifications in horse gram (Macrotyloma uniflorum)

2021 ◽  
Vol 42 (5) ◽  
pp. 1363-1369
Author(s):  
S. Priyanka ◽  
◽  
R. Sudhagar ◽  
C. Vanniarajan ◽  
K. Ganesamurthy ◽  
...  

Aim: The quest was framed to analyse the effect of high dose of gamma rays on morphological, flowering, and palynological traits in horse gram (Macrotyloma uniflorum). Methodology: Two horse gram varieties PAIYUR 2 and CRIDA 1-18 R were mutated using 32 mutagenic combinations. Sterile plants produced by gamma rays: 400 Gy were utilized to study the alterations in morphological, flowering characters in 20 randomly selected plants, and palynological traits using scanning electron microscope. Results: Gamma rays (GR):400 Gy produced sterile plants with altered ideotype and reproductive traits. It reduced expression of yield attributing traits, delayed first flowering, modified anther, and pollen size. The palynological changes included genotype dependant variation in pili number, size and exine ornamentation. Interpretation: High gamma ray dose is lethal to horse gram which was evidenced through grave modifications in morphological and palynological traits. These alterations resulted in sterility. Sterile plants tried to repair the irradiation induced damages and hence failed to perform routine reproductive functions.

Phytotaxa ◽  
2021 ◽  
Vol 516 (3) ◽  
Author(s):  
PRADIP VIKRAM DESHMUKH ◽  
SIDDHARTHAN SURVESWARAN ◽  
RAMCHANDRA DNYANOBA GORE ◽  
MANOJ MADHWANAND LEKHAK

The endemic Indian genus Haplanthodes (Acanthaceae) is revised. Four species, viz. H. neilgherryensis, H. plumosa, H. tentaculata and H. verticillata and a new variety, H. neilgherryensis var. toranganensis are recognized. Lectotype is designated for Haplanthodes, Haplanthus plumosus and H. verticillaris. The nomenclature of the Linnaean name Ruellia tentaculata is also discussed. Micromorphology of seed using light microscope (LM) and scanning electron microscope (SEM) is observed for the first time, and two types, reticulate and micro papillate, have been recognized based on surface sculpturing pattern. The genus differs from the related genera Andrographis and Haplanthus by distinctly two grooved seeds with hygroscopic hairs. Pollen grains of the genus are oblate or prolate spheroidal, distinctly triangular, trizonocolporate with reticulate exine ornamentation.


Polymers ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 111 ◽  
Author(s):  
Jin-Oh Jeong ◽  
Jong-Seok Park ◽  
Young-Ah Kim ◽  
Su-Jin Yang ◽  
Sung-In Jeong ◽  
...  

Conducting polymer (CP)-based hydrogels exhibit the behaviors of bending or contraction/relaxation due to electrical stimulation. They are similar in some ways to biological organs and have advantages regarding manipulation and miniaturization. Thus, these hydrogels have attracted considerable interest for biomedical applications. In this study, we prepared PPy/PVP hydrogel with different concentrations and content through polymerization and cross-linking induced by gamma-ray irradiation at 25 kGy to optimize the mechanical properties of the resulting PPy/PVP hydrogel. Optimization of the PPy/PVP hydrogel was confirmed by characterization using scanning electron microscopy, gel fraction, swelling ratio, and Fourier transform infrared spectroscopy. In addition, we assessed live-cell viability using live/dead assay and CCK-8 assay, and found good cell viability regardless of the concentration and content of Py/pTS. The conductivity of PPy/PVP hydrogel was at least 13 mS/cm. The mechanical properties of PPy/PVP hydrogel are important factors in their application for biomaterials. It was found that 0.15PPy/PVP20 (51.96 ± 6.12 kPa) exhibited better compressive strength than the other samples for use in CP-based hydrogels. Therefore, it was concluded that gamma rays can be used to optimize PPy/PVP hydrogel and that biomedical applications of CP-based hydrogels will be possible.


Author(s):  
V. Pushpayazhini ◽  
R. Sudhagar ◽  
C. Vanniarajan ◽  
S. Juliet Hepziba ◽  
J. Souframanien

Background: Horse gram is the potential rainfed legume in Indian farming. The major limitation in horse gram breeding is the narrow variability. Variability induction and its estimation would sustain food security. Methods: Variability was induced using gamma rays, electron beam and ethyl methanesulfonate and their combinations. The induced variation for the economic traits, their inheritance and genetic gain were ascertained. Result: The analysis of variance indicated the induction of significant variation for yield attributing traits. The population was grouped into 10 constellations by the virtue of induced variation. The groups I, II and V were the largest comprising of 38, 31 and 19 mutants respectively. The mutants exhibited significant intra and inter group variation. The mutagens induced the maximum variability for plant height (32.24%), 100 seed weight (25.42%) and number of pods per plant (19.18%). The mutants possessed high genotypic and phenotypic coefficients of variation for all the characters except flowering traits and duration. The induced variability for the yield attributing traits possessed significant breeding value as the heritability (86.66%-99.72%) and genetic advance as percent of mean (10.65-81.94) were high and the environmental influence was the minimum.


Phytotaxa ◽  
2019 ◽  
Vol 397 (3) ◽  
pp. 213 ◽  
Author(s):  
BURCU YILMAZ ÇITAK

The present study reports for the first time detailed palynological traits of the Turkish species Iberis. Both light microscope (LM) and scanning electron microscope (SEM) were used for the characterisation of the species. Radially symmetrical, isopolar, and tricolpate pollen grains were observed as common characters in all of the examined taxa. The pollen grains were prolate-spheroidal with polar axes ranging from 21.97 to 29.25 µm and equatorial axes ranging from 20.34 to 26.09 µm. Their polar shapes were subcircular to subtriangular. Two types of exine ornamentation were observed using a SEM. A numerical UPGMA analysis showed that the dimensions of polar axes, equatorial axes and outline in polar view (amb) were the most valuable variables for separating the Iberis species.


2019 ◽  
Vol 53 (15) ◽  
pp. 2065-2076 ◽  
Author(s):  
Elham M Hegazi ◽  
HM Eyssa ◽  
AA Abd El-Megeed

The effect of high gamma irradiation and nanosilica on the structure and mechanical properties of the acrylonitrile butadiene rubber seal materials was investigated in this study. Acrylonitrile butadiene rubber nanocomposites containing (25, 50 and 75 phr) unmodified and modified nanosilica were irradiated at different doses (0, 0.2, 0.4, 0.6, 0.8, 1 MGy). The dispersion of nanosilica-based filler in acrylonitrile butadiene rubber was investigated by scanning electron microscope. Fourier-transform infrared analysis, swelling, crosslinking, mechanical and the thermal resistance properties of acrylonitrile butadiene rubber nanocomposites were investigated. From the results, it is clear that with modified nanosilica, acrylonitrile butadiene rubber phase crosslinking is accelerated with increasing γ-doses compared to unmodified nanosilica and seems to enhance physical, mechanical and the thermal properties of the rubber. The surface of the acrylonitrile butadiene rubber nanocomposites was investigated by scanning electron microscope and found better dispersion for acrylonitrile butadiene rubber with 25 phr of modified nanosilica at 0.6 MGy. The compression set of the results indicated that 25 phr modified nanosilica has best properties under high gamma irradiation.


2011 ◽  
Vol 39 (2) ◽  
pp. 223-228 ◽  
Author(s):  
AN Gomurgen ◽  
I Potoglu Erkara ◽  
H Altnozlu

Chromosome and pollen morphology of Centaurea lycopifolia Boiss. & Kotschy were studied. The chromosome number is 2n = 34 with haploid karyotype formula 9m + 9sm. Metaphase chromosome length ranging from 6.16 to 2.23 μm and the total haploid chromosome length was 65, 85 μm. The light and scanning electron microscope investigations revealed spheroidal-subprolate, the amb triangular and tricolporatae pollens in the taxon. Exine ornamentation was tectatae and microechinate-scabrate. Key words: Centaurea lycopifolia; Chromosome; Pollen morphology; Endemic; Turkey DOI: 10.3329/bjb.v39i2.7484 Bangladesh J. Bot. 39(2): 223-228, 2010 (December)


2014 ◽  
Vol 73 (1) ◽  
pp. 90-103 ◽  
Author(s):  
Shahryar Saeidi Mehrvarz ◽  
Narjes Yousefi ◽  
Maryam Mohammadi ◽  
Thomas Marcussen

AbstractPollen morphology of 17 species of Viola representing five sections, Melanium, Plagiostigma, 'Spathulidium' ined., Sclerosium, and Viola, was studied using light and scanning electron microscope. Pollen grains were usually symmetrical, tetrazonocolporate to pentazonocolporate in section Melanium and trizonocolporate to tetrazonocolporate in the other four sections. Pollen shape was circular to subtriangular, tetragonal or pentagonal in polar view and prolate to oblate, spheroidal or pyramidal in equatorial view. Exine ornamentation was granulate, psilate and mostly perforate. The psilate type was only observed in V. modesta.We found heteromorphy in aperture number in V. caspia of section Viola, V. occulta of section Melanium and V. behboudiana of section Sclerosium, which corroborates their higher ploidy than in related species (octoploid versus tetraploid).


2021 ◽  
Vol 11 (9) ◽  
pp. 1561-1570
Author(s):  
Yuanyuan Li ◽  
Shuzhi Sam Ge ◽  
Kun Mo ◽  
Biao Liu

As polymers, rubber materials are easily affected by radiation; therefore, their radiation resistance must be considered for their use in robots and automation equipment in high-radiation environments. In this study, the properties of several common rubber materials, ethylene propylene diene monomer (EPDM), nitrile rubber (NBR), hydrogenated nitrile rubber (HNBR), fluororubber (FKM), and acrylate rubber (ACM), were investigated under high-dose gamma-ray irradiation. The dose rate of gamma rays was 66.76 Gy/min, and the cumulative dose was 1214965.24 Gy. Oxidative decomposition of the double bond of EPDM occurred, leading to slight decreases in the strength and elongation. NBR and HNBR were mainly subjected to crosslinking of the molecular structure, resulting in small increases in strength and significant decreases in elongation. The cyano decomposition reaction occurred in ACM, and its crystallinity increased, leading to embrittlement and decreases in the strength and elongation. Oxidative decomposition and cross-linking simultaneously occurred in FKM, resulting in an increase in strength and decreases in elongation and the elastic modulus.


1967 ◽  
Vol 31 ◽  
pp. 469-471
Author(s):  
J. G. Duthie ◽  
M. P. Savedoff ◽  
R. Cobb
Keyword(s):  

A source of gamma rays has been found at right ascension 20h15m, declination +35°, with an uncertainty of 6° in each coordinate. Its flux is (1·5 ± 0·8) x 10-4photons cm-2sec-1at 100 MeV. Possible identifications are reviewed, but no conclusion is reached. The mechanism producing the radiation is also uncertain.


1994 ◽  
Vol 144 ◽  
pp. 635-639
Author(s):  
J. Baláž ◽  
A. V. Dmitriev ◽  
M. A. Kovalevskaya ◽  
K. Kudela ◽  
S. N. Kuznetsov ◽  
...  

AbstractThe experiment SONG (SOlar Neutron and Gamma rays) for the low altitude satellite CORONAS-I is described. The instrument is capable to provide gamma-ray line and continuum detection in the energy range 0.1 – 100 MeV as well as detection of neutrons with energies above 30 MeV. As a by-product, the electrons in the range 11 – 108 MeV will be measured too. The pulse shape discrimination technique (PSD) is used.


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