Different Doses Of Gamma Rays Research Articles

Influence of gamma-irradiation on the physical properties of epoxy/polyaniline composites and application as gamma dosimeter

Abstract The epoxy/pani samples doped with a specified weight ratio of polyaniline pani ware prepare by casting method. Using different doses of gamma rays (0, 2, and 4 kGy) were used to irradiated the prepared samples. Irradiated and non-irradiated samples were imaged using a FE-scanning electron microscope and were found to have regular morphology, and irradiation had obvious effect on this morphology at 4 kGy. When studying the crystal structure of the samples, it was found the samples have a polycrystalline structure, and this structure tends to improve after irradiation, this was verified using X-ray diffraction. Likewise, D.C electrical conductivity increased with increasing gamma radiation doses. Also study the effect of irradiation with gamma rays on optical properties and demonstrate the clear effect of these rays on optical properties. It was also found that the optical energy gap with (indirect allowed transition) was decreases after the irradiation process. Together, these results indicate the possibility of using these samples in the manufacture of gamma dosimeters.

Effects of irradiation on the survival of Sarcocystis bradyzoites in beef.

Sarcocystis is a food-borne zoonotic protozoan whose final hosts are humans, dogs, cats, and other carnivores and intermediate hosts are birds and mammals, especially humans and herbivores. Humans become infected by eating raw and undercooked meat contaminated with bradyzoites or by consuming water or food contaminated with the sporocyst stage of the parasite. The aim of this study was to investigate the effects of gamma radiation and electron beam on the survival rate of Sarcocystis bradyzoites in infected beef and to determine the effective dose. Three replicates of 100g of infected meat were treated with different doses (0.5, 1, 1.5 and 2kGy). As a control, 20g of contaminated meat was stored separately at 4°C. The viability of the bradyzoites after digestion in pepsin solution was assessed, stained (trypan blue) and unstained, under a stereomicroscope. To assess survival of the bradyzoites, the irradiated meat samples were fed to 30 dogs. After 10 days, faecal samples were examined for sporocysts. The results showed that the highest and lowest mortality rate of Sarcocystis bradyzoites in infected organs using electron beam at a dose of 2kGy were 92.5% and 100%, respectively, and the lowest mortality rate at a dose of 0.5kGy were 2.5% and 7.89%, respectively. The results of statistical analysis showed that the mortality rate of Sarcocystis bradyzoites was significant between different doses of gamma ray and electron beam, so that gamma rays were better compared to electron beam in destroying Sarcocystis bradyzoites.

A comparative study of the mechanical and thermal properties of EPDM rubber/cement kiln dust composite cured by ionizing radiation

In this work, cement kiln dust (CKD) will be studied as an unconventional filler for ethylene-propylene-diene terpolymer (EPDM) rubber as an alternative to silica, which is widely used as filler for many types of rubber. (EPDM)/CKD rubber composites were fabricated using ionizing radiation. EPDM rubber was blended with different portions of cement-kiln dust 5, 10, 15, 20, 25, and 30 phr (phr = parts per hundred rubber). The prepared composites were cured by exposing to different doses of gamma rays up to 150 kGy to enhance the crosslinking of the EPDM rubber. The thermo-mechanical properties of the EPDM/CKD and EPDM/Si composites were investigated as a function of irradiation dose. The results showed a significant improvement in elongation and tensile strength by incorporating cement dust into EPDM rubber up to 20 phr, which is not significantly different from composites incorporated with silica. Gamma irradiation significantly improved the properties of all formulations.

Inducing potential mutants in rice using different doses of gamma rays for improving agronomic traits

Inducing potential mutants in rice using different doses of gamma rays for improving agronomic traits

Gamma radiation-induced alterations in nanocrystalline titanium nitride (TiN) particles: A structural perspective

The effect of gamma radiation on the structure of nanocrystalline TiN particles was studied. Initially, nanocrystalline TiN particles were exposed to gamma radiation at doses of 50 kGy, 200 kGy, 900 kGy and 3.5 MGy. The crystal structure of non-irradiated and irradiated samples with different doses of gamma rays was studied by X-ray diffraction method. As a result of the determination analysis of the X-ray diffraction spectra by the Rietvield method, the dependence of the lattice parameters on the radiation dose was established. The effect of gamma irradiation on the size of crystallites was determined by the Scherrer equation. The amorphization occurred in nanocrystalline TiN particles was calculated by the method of integration of diffraction peaks. It was determined that 2.5% amorphization occurred in the specified irradiation interval.

Increased yield performance of mutation induced Soybean genotypes at varied agro-ecological conditions.

In soybean breeding program, continuous selection pressure on traits response to yield created a genetic bottleneck for improvements of soybean through hybridization breeding technique. Therefore an initiative was taken to developed high yielding soybean variety applying mutation breeding techniques at Plant Breeding Division, Bangladesh Institute of Nuclear Agriculture (BINA), Bangladesh. Locally available popular cultivar BARI Soybean-5 was used as a parent material and subjected to five different doses of Gamma ray using Co60. In respect to seed yield and yield attributing characters, twelve true breed mutants were selected from M4 generation. High values of heritability and genetic advance with high genotypic coefficient of variance (GCV) for plant height, branch number and pod number were considered as favorable attributes for soybean improvement that ensure expected yield. The mutant SBM-18 obtained from 250Gy provided stable yield performance at diversified environments. It provided maximum seed yield of 3056 kg ha-1 with highest number of pods plant-1 (56). The National Seed Board of Bangladesh (NSB) eventually approved SBM-18 and registered it as a new soybean variety named 'Binasoybean-5' for large-scale planting because of its superior stability in various agro-ecological zones and consistent yield performance.

Mutagenic sensitivity analysis in soybean (Glycine Max L. Merill)

The seeds of soybean were treated with nine different doses of Gamma rays and six different doses of EMS to study the mutagenic sensitivity of physical and chemical mutagen. The treated seeds along with control were sown to raise M1 generation. Germination percentage was recorded in laboratory as well as in the field condition the higher doses showed drastic reduction in germination, and survival percentage. The Probit analysis showed that the LD50 value of Gamma rays based on laboratory and field germination was 335.68 Gy and 283.40 Gy respectively while for EMS it was 0.28% and 0.23% respectively.

Genotype‐by‐environmental interaction effects on earliness, semi‐dwarfism, and yield of rice (Oryza sativa L.) mutants in Tamil Nadu, India

AbstractRice plant architecture improvement helps in the effective and efficient source–sink relationship to enhance yield. The most preferred plant architecture in rice is dwarf type. Improved White Ponni (IWP) is a tall, medium duration, released variety of Tamil Nadu, India, yielding 300 kg more than parental line White Ponni, which is suitable for second season transplanting. To induce variation in plant height to select semi‐dwarf mutants, IWP was subjected to mutagenesis in 2011 using different doses of gamma rays to develop semi‐dwarf and short‐duration mutants. The selection was carried out in segregating populations of M2, and an evaluation of selected better‐performing mutants was done up to 70 selected mutants in M5. Nineteen M5 homozygous, semi‐dwarf, and short‐duration mutants that outperformed the IWP were evaluated in 2015–2016 across five contrasting environments of Tamil Nadu in India. The genotypes were grown in a randomized complete block design with two replications with IWP as a control. In the additive main effects and multiplicative interaction (AMMI) biplot, the analysis revealed that PC1 and PC2 accounted for 49% and 18% of the variation, respectively. Interaction principal component analysis‐1 scores were observed for the mutants, viz., IWP‐15‐5, IWP‐22‐1, and IWP‐30‐5, indicating their superior performance. In the GGE biplot, E1 (Aduthurai), E4 (Coimbatore), and E5 (Thirupathisaram) were the ideal environments for selecting high‐yielding mutants. IWP‐6‐5 and IWP‐16‐2 were the stable mutants for yield (23.59 and 24.51 g, respectively) but with a lower mean than other mutants at favorable environments. Based on the two models, E2 (Killikulam) and E3 (Madurai) were the favorable locations for exploiting high yields; IWP‐30‐5, IWP‐22‐2, and IWP‐22‐3 were stable across environments. These stable, high‐yielding, and early maturing mutants show potential for further advancement and eventual release of new rice varieties.

Delineation of selection criterion using pearson correlation and path coefficient analysis in mutant mungbean (Vigna radiata) lines

An experiment was conducted at the research farm of Sardarkrushinagar Dantiwada Agricultural University, Sardarkrushinagar, Gujarat to evaluate plant characteristics associated with grain yield and its attributes in mutant mungbean (Vigna radiata L.) lines in north Gujarat condition through correlation and path analyses during 2019. Eight independent and 1 dependent variable were evaluated for the character association analysis of the 1200 mutant mungbean lines. The uniform, healthy and dry seeds of mungbean variety GM 4 were treated with 4 different doses of gamma rays at B. A. R. C, Trombay, Mumbai during summer 2019. Selection and evaluation was performed till the M2 generation and final M3 generation was grown using augmented design in 21 blocks containing 57 selections and 3 checks. Five plants selected randomly from each replicated lines and subjected to data assortment and analysisusing OPSTAT. The seed yield was significantly and positively associated with both number of clusters per plant and number of pods per plant. Same traits, as concluded through the path analysis, had a significant positive direct effect on seed yield. Moderate magnitude of indirect positive effect was detected for number of cluster per plant thorough number of pod per plant (0.162). In order to achieve proper array of relation on seed yield, more traits need to be included in the study, clearly evidenced by the high residual effect of path analysis (0.535). Heatmap interpretation reveals colour grading according to the degree of correlation among the traits. Selection method entered on these 2 traits along with others will be productive to increase seed yield in mungbean.

Field assessment of yield and its contributing traits in cowpea treated with lower, intermediate, and higher doses of gamma rays and sodium azide.

Across the globe, plant breeders of different organizations are working in collaboration to bring preferred traits to crops of economic importance. Among the traits, "high yielding potential" is the most important as it is directly associated with food security and nutrition, one of the sustainable development goals. The Food and Agriculture Organization acknowledges plant breeders' role and efforts in achieving local and global food security and nutrition. Recognizing the importance of pulses and increasing pressure on food security, the United Nations General Assembly declared 2016 the "International year of Pulses" owing to their preferred traits such as climate change resilience, wide adaptability, low agriculture input, and protein- and nutrient-rich crops. Keeping all these developments in consideration, we initiated an induced mutagenesis program by treating cowpea (Vigna unguiculata L. Walp.) with different doses of gamma rays and sodium azide aiming to enhance the yielding potential of an otherwise outstanding variety viz., Gomati VU-89 and Pusa-578. We noticed a substantial increase in mean values of agronomic traits in putative mutants raised from seeds treated with lower and intermediate doses of mutagens. Statistical analysis such as correlation, path, hierarchical clustering analysis (HCA), and principal component analysis (PCA) were used to assess the difference between mutagenized and control populations. A significant and positive correlation of yield with yield-attributing traits was recorded. However, among all the yield attributing traits, seeds per pod (SPP) depicted the maximum direct impact upon yield, and therefore, working on this trait may yield better results. A widely used PCA revealed 40.46% and 33.47% of the total variation for var. Gomati VU-89 and var. Pusa-578, respectively. Cluster analysis clustered treated and control populations into separate clusters with variable cluster sizes. Cluster V in the variety Gomati VU-89 and cluster V and VI in the variety Pusa 578 comprised of putative mutants were higher yielding and hence could be recommended for selection in future breeding programs. We expect to release such mutant lines for farmer cultivation in Northern parts of India depending on the performance of such high-yielding mutant lines at multilocations.

INDUCCIÓN DE VARIABILIDAD EN EL VIGOR DE PLÁNTULA, CARACTERES MORFOLÓGICOS Y AUTOINCOMPATIBILIDAD DE PLANTAS M1 DE TRES VARIEDADES DE Physalis ixocarpa Brot. MEDIANTE RAYOS GAMMA 60Co

<p><strong>Background. </strong>The husk tomato (<em>Physalis ixocarpa</em> Brot. ex Horm.) is an obligated allogam species with gametophyte auto-incompatibility, which impedes the generation of endogamic lines by auto-fecundation to obtain hybrids. <strong>Objective.</strong> To evaluate the effect of six doses of <sup>60</sup>Co gamma rays (from 0 to 300 Gy) applied to seeds, over seedling vigor, growth and reproductive features of M<sub>1</sub> plants of three husk tomato varieties (Manzano, Verde Puebla, and San Miguel). <strong>Methodology.</strong> The 18 treatments were distributed in a completely randomized design with five replications for the variables related to seedling vigor and 10 replications for the morphological and reproductive plant variables. <strong>Results.</strong> The radiation decreased emergency and survival of seedlings, height, and length of roots of M<sub>1</sub> seedling. Regarding the growth of M<sub>1</sub> plants, the doses of 100 and 300 Gy stimulated only height, the other doses had the same response as the control. Irradiation did not change self-incompatibility, as no fruit produced seed. <strong>Implications.</strong> The study allows to determine the sensitivity of the peel tomato to irradiation, by subjecting seeds to different doses of gamma rays and assess whether it is possible to obtain outstanding individuals in force and flowers that present self-fertilization, considering all the advantages of this type of pollination (form lines, to generate hybrids). <strong>Conclusions.</strong> The M<sub>1</sub> plants of the varieties Manzano and Verde Puebla excelled in growth; but those of San Miguel presented more self-pollinated flowers. The three varieties resulted sensitive to radiation; but growth variables varied depending on the variety and dose of radiation.<strong></strong></p>

Titer improvement of mycophenolic acid in the novel producer strain Penicillium arizonense and expression analysis of its biosynthetic genes

Mycophenolic acid (MPA) is the active ingredient in the most important immunosuppressive pharmaceuticals. It has antifungal, antibacterial, antiviral, anti-psoriasis, and antitumor activities. Therefore, its overproduction in addition to gene expression analysis was our main target. Through this study, we isolated a novel potent mycophenolic acid (MPA) producer strain of the genus Penicillium from the refrigerated Mozzarella cheese and it was identified with the molecular marker ITS and benA genes as P. arizonenseHEWt1. Three MPA overproducer mutants were isolated by exposing the wild type to different doses of gamma-rays, and the fermentation conditions for the highest production of MPA were optimized. The results indicated that MPA amounts produced by the mutants MT1, MT2, and MT3 were increased by 2.1, 1.7, and 1.6-fold, respectively, compared with the wild-type. The growth of both mutant and wild-type strains on PD broth, adjusted to pH 6 and incubated at 25 °C for 15 d, were the best conditions for maximum production of MPA. In a silico study, five orthologs genes of MPA biosynthesizing gene clusters in P. brevicompactum were predicted from the genome of P. arizonense. Sequencing and bioinformatic analyses proved the presence of five putative genes namely mpaA, mpaC, mpaF, mpaG, and mpaH in the P. arizonense HEWt1 genome. Gene expression analysis by qRT-PCR indicated an increase in the transcription value of all annotated genes in the three mutants over the wild type. A highly significant increase in the gene expression of mpaC, mpaF, and mpaH was observed in P. arizonense-MT1 compared with wild-type. These results confirmed the positive correlation of these genes in MPA biosynthesis and are the first report regarding the production of MPA by P. arizonense.Kew word.Mycophenolic acid, Penicillium arizonense, mutagenesis, gene expression.

Characterization of gamma ray induced mutations in PepYLCV-infecting local pepper in Karo Regency, Sumatra Utara, Indonesia

Plant mutation breeding plays a pivotal role in increasing plant genetic variability, pest and disease resistance and yield production. Gamma ray irradiation induced to infected plants to obtain resistant mutant plants. This research aims to examine the morphological characterization of pepper plants and the mutant plants produced from irradiated PepYLCV-infecting local pepper from Karo Regency, Sumatra Utara, Indonesia. The research was conducted in January to October 2021 in farming land in Tongkoh Village, Dolat Rayat District, Karo Regency, Sumatra Utara, using non-Factorial Randomized Block Design. The mutation was induced by exposing the seeds of local chili to varied doses (D): 0 (uninfected seeds and unirradiated infected seeds), 150, 200 and 250 Gy and was performed using T-Test, replicated 3 times. The results of research showed that different doses of gamma rays significantly affected the mutant plants from the observation on its plant height, stem diameter, canopy and fruit lengths, fruit weight, number of branches, leaves and fruits. Plant induced with gamma ray 150 Gy found to have the longest canopy and fruit and also demonstrated the highest number of branches, flowers, leaves and the highest fruit weight compared to other higher doses. The exposure of gamma irradiation gave positive effect to infected chili to enhance their resistance in order to produce higher yield.

Mutagenic-sensitivity and variability in the putative mutants of polyembryonic mango genotypes

Polyembryonic mango genotypes are considered the best resources for developing rootstocks owing tothe production of uniform, true-to-type nucellar seedlings with the deep tap root systems. However, their use inbreeding programmes is often limited by a narrow genetic base due to maternal inheritance. Hence, enhancementin or creation of variability for traits of interest becomes a pre-requisite, if rootstock breeding in mango has tobe undertaken. In this study, we attempted to induce variability in polyembryonic mango genotypes, Bappakkai,Nekkare and Kurukkan by treating their kernels with different doses of gamma rays ranging from 15 to 35 Gy.The results revealed delayed germination and a decrease in germination percentage with increasing dosageof gamma irradiation. The lethal dose (LD50) values for gamma radiation were determined, based on the seedgermination percentage using Probit analysis values, which were 22.39 Gy, 19.95 Gy, and 19.95 Gy for Bappakai,Nekkare and Kurukkan, respectively. Other traits like the number of seedlings emerging per kernel, plant height,inter-nodal length, and the number of leaves showed a gradual decrease in their mean values with increasingirradiation dosage. The results suggest the effectiveness of induced mutation in bringing about variability intraits like plant height for developing dwarf rootstocks to be used in high-density planting.

Synthesis and characterization of gamma irradiated polyvinyl chloride/graphite carbon nitride nanocomposite films for electronic applications

This study introduces the synthesis of graphite-carbon nitrite (g-C3N4) using thermal treatment of urea. The prepared powder is treated to generate nanoparticles. The structure and grain size of the g-C3N4 have been obtained via X-ray diffraction (XRD) technique and transmission electron microscope. The graphite-carbon nitride on Polyvinyl Chloride (PVC/g-C3N4) nanocomposite films were produced by mixing different concentrations (0, 3, 5, 7, 10 and 20 wt%) of nanoparticles with Polyvinyl Chloride (PVC) solutions. The structure and elemental composition of the prepared nanocomposites films PVC/g-C3N4 were studied by using XRD, scanning electron microscope (SEM), (EDX), infrared spectroscopy (IR) and electron spin resonance (ESR). Also, spectral distribution of the optical absorbance for the PVC/g-C3N4 nanocomposites films was studied in the wavelength range from 190 to 1100 nm. Thermal stability of the investigated nanocomposites films was investigated by thermal gravimetric analysis technique (TGA). The effect of various concentrations of the g-C3N4 and different doses of gamma-rays on the polymeric matrix and electrical properties of PVC film also has been investigated. The g-C3N4 additives on PVC influenced the crystal structure and optical properties of the nanocomposites films. The nanocomposite film with 10% g-C3N4 achieved higher values of the refractive index and optical conductivity compared with the other films. With different doses of gamma-ray irradiation, the crystal structure and optical properties of PVC/g-C3N4 nanocomposite films were changed in accordance to the cross-linking process within the PVC polymeric chains where a structural rearrangement can be occurred as a result of gamma irradiation. The elemental composition and morphological study of PVC/g-C3N4 nanocomposite films have been checked by the scanning electron microscopy which indicated the homogeneous dispersion of g-C3N4 nanoparticles within PVC network. Finally, electrical properties of PVC/g-C3N4 nanocomposite films with different ratios and distinct gamma doses also have been studied.

Acquired radioresistance in EMT6 mouse mammary carcinoma cell line is mediated by CTLA-4 and PD-1 through JAK/STAT/PI3K pathway

Cancer recurrence is often associated with the acquisition of radioresistance by cancer tissues due to failure in radiotherapy. The underlying mechanism leading to the development of acquired radioresistance in the EMT6 mouse mammary carcinoma cell line and the potential pathway involved was investigated by comparing differential gene expressions between parental and acquired radioresistance cells. EMT6 cell line was exposed to 2 Gy/per cycle of gamma-ray and the survival fraction between EMT6-treated and parental cells was compared. EMT6RR_MJI (acquired radioresistance) cells was developed after 8 cycles of fractionated irradiation. The development of EMT6RR_MJI cells was confirmed with further irradiation at different doses of gamma-ray, and both the survival fraction and migration rates were measured. Higher survival fraction and migration rates were obtained in EMT6RR_MJI cells after exposure to 4 Gy and 8 Gy gamma-ray irradiations compared to their parental cells. Gene expression between EMT6RR_MJI and parental cells was compared, and 16 genes identified to possess more than tenfold changes were selected and validated using RT-PCR. Out of these genes, 5 were significantly up-regulated i.e., IL-6, PDL-1, AXL, GAS6 and APCDD1. Based on pathway analysis software, the development of acquired radioresistance in EMT6RR_MJI was hypothesized through JAK/STAT/PI3K pathway. Presently, CTLA-4 and PD-1 were determined to be associated with JAK/STAT/PI3K pathway, where both their expressions were significantly increased in EMT6RR_MJI compared to parental cells in the 1st, 4th and 8th cycle of radiation. As a conclusion, the current findings provided a mechanistic platform for the development of acquired radioresistance in EMT6RR_MJI through overexpression of CTLA-4 and PD-1, and novel knowledge on therapeutic targets for recurrent radioresistant cancers.

Exploring the Relationship between Yield and Its Attributing Traits in the Induced (M2) and Recurrent Irradiated (RM2) Population of Finger Millet (Eleusine coracana L. Gaertn) Using Path Coefficient Analysis

Mutation breeding has evolved as an efficient tool for creating novel variability. Induced mutagenesis is the method of treating the base material only once, whereas recurrent mutagenesis involves subjecting the first generation (M1) to another dose of mutagen for creating extensive spectrum of genetic variations in the population. Path coefficient analysis in the induced and recurrent irradiated population measures the strength of relationship between yield attributing traits and grain yield, both directly and indirectly. The present investigation was undertaken during Kharif, 2019-20 at the K block, GKVK, University of Agricultural Sciences, Bangalore. The two genotypes of finger millet viz., GPU 28 and KMR 204 have undergone single and recurrent irradiation with different doses of gamma rays (300Gy, 400Gy) and EMS (0.1%) at Bhaba Atomic Research Centre, Mumbai. Observations were recorded for 9 quantitative traits viz., days to 50% flowering, plant height, productive tillers plant-1, ear head plant-1, fingers ear-1, finger length, panicle weight plant-1(g), test weight (g) and grain yield plant-1 (g). The studies on path analysis revealed that panicle weight and test weight established positive and direct effect towards grain yield in the induced population of finger millet. Similarly, in the recurrent irradiated population with gamma rays panicle weight, test weight, finger ear-1, 50% flowering, ear plant-1 and finger length showed direct positive effect for grain yield whereas in the recurrent irradiated population with EMS panicle weight followed by test weight, fingers ear-1, plant height, productive tillers plant-1, finger length and 50 % flowering exhibited direct positive effect for grain yield. Henceforth, direct selection based on grain yield and its attributing traits would benefit in developing high yielding variety in the crop improvement programme of finger millet.

Evaluation of Advanced Mutant Restorer Lines for Enhancing Outcrossing Rate and Hybrid Seed Production of Diverse Rice Cytoplasmic Male Sterile Lines

Hybrid rice seed production predominantly relies on the pollen ability of restorer lines and the stigma properties of the cytoplasmic male sterile (CMS) lines. Improving the pollen ability and agronomic performance of restorer lines could be achieved using mutation to reinforce the outcrossing rate and seed set percentage of CMS lines. Two commercial restorer cultivars (Giza-178 and Giza-179) were treated with three different doses of gamma-ray; 200, 300, and 400 Gy. The derived mutant restorer lines were selfed and constantly evaluated with their corresponding parental cultivars until the M6 generation. Six promising mutant lines were chosen based on their performance to be evaluated with their parents for their pollen and agronomic characteristics. The novel-induced mutant restorer lines exhibited significant differences in all studied pollen and agronomic characteristics. The mutant restorer lines R4 and R7 exhibited superior desirable anther length (2.36 and 2.38 mm, in the same order), anther width (0.47 and 0.45 mm), pollen fertility (97.50 and 97.31%), basal pore length (218.8 and 299.5 mm), apical length (103.6 and 108.1), number of pollen grains per anther (1810 and 1832), plant height (121.8 and 115.9 cm), fertile tillers (23.50 and 18.89), number of spikelets per panicle (203.2 and 202.5), panicle length (25.34 and 24.26 cm), number of filled grains per panicle (195.5 and 191.8), seed set percentage (95.56 and 96.63%), and grain yield (11.01 and 11.36 t/ha). Based on the results of the first two seasons, the two novel promising restorers and their parental cultivars were crossed with four diverse CMS lines. The seed set percentage and hybrid seed production of the crossed CMS lines were evaluated for further two seasons. The results exposed that the combinations derived from restorer lines R4 and R7 with most of the evaluated CMS lines produced the uppermost seed set percentage outcrossing rate. Particularly in combination with CMS2, the restorer lines R4 and R7 displayed the highest seed set percentage (39.57 and 34.80%), number of tillers fertile per hill (25.31 and 23.32), seed yield (2.02 and 1.81 t/ha), and harvest index (23.88 and 22.66%). Conclusively, the derived gamma-ray-induced mutant restorer lines R4 and R7 could be exploited as a new source for ensuring desirable pollen and anther characteristics in order to improve the outcrossing rate of CMS lines and hybrid rice seed production.

Caenorhabditis elegans NHR-14/HNF4α regulates DNA damage-induced apoptosis through cooperating with cep-1/p53

BackgroundNuclear hormone receptors are involved in transcriptional regulation and many important cellular processes including development and metabolism. However, its role in DNA damage-induced apoptosis remains elusive.MethodsSynchronized young adult animals were irradiated with different doses of gamma-Ray, and then put back to culture at 20 °C. Germline cell apoptosis was scored at different time point.ResultsDeletion of nhr-14 led to decreased DNA damage-induced germline apoptosis, but not the physiological programmed cell death. We also demonstrate that nhr-14 functions downstream of the DNA damage checkpoint pathway. Moreover, we show that nhr-14 regulates egl-1 and ced-13 transcription upon DNA damage. Mechanistically, NHR-14 forms a complex with CEP-1/p53 and binds directly to the egl-1 promoter to promote egl-1 transcription..ConclusionsOur results indicate that NHR-14/HNF4α cooperates with CEP-1/p53 to regulate DNA damage-induced apoptosis.Graphic abstract3SXEF2qkT2QHPu1N_hpJxUVideo abstract

Resolving the acute gamma irradiation and ethyl methanesulphonate induced lethality for Jasminum sambac L. (Aiton) cv. Ramanathapuram Gundumalli

Crop improvement in Jasminum sambac through induced mutagenesis entails the insight on the sensitiveness of the individual plant materials of a species to different classes and nature of the mutagens. The current assessment was undertaken to analyse the mutagenic effect of acute gamma irradiation and EMS in Jasminum sambac cv. Ramanathapuram Gundumalli. Semi-hardwood cuttings of the plants were exposed to different dosage levels of gamma rays varying from 0 Gy (control) to 40 Gy and decapitated rooted cuttings were treated with EMS from 0 mM (control) to 90 mM. The M1V1 generation was evaluated by treating the cuttings with four different doses of gamma rays (15 Gy, 20 Gy, 25 Gy and 30 Gy) and three concentrations of EMS (45 mM, 60 mM, 75 mM) formulated using respective LD50 doses.  The lethality dosage (LD50) value for the cultivar Ramanathapuram Gundumalli was determined to be 21.37 Gy and 64.57 mM for gamma irradiation and EMS, respectively applying the probit curve analysis. The maximal reduction in the survival of cuttings of 75% and 71% correspondingly in gamma and EMS treatments was discerned at higher doses in comparison to the lower doses. The plants studied in M1V1 generation for growth and flowering characters exhibited variable responses pertaining to differing doses or concentrations of the specific mutagenic means. Keywords: Jasminum sambac, gamma irradiation, EMS, LD50 and semi-hardwood cuttings