The current investigation was carried out to study the effect of different doses of gamma irradiation on in vitro shoot cultures of carnation (Dianthus caryophyllus L.) and characterization of mutants using ISSR markers. The trial was undertaken at the experimental farm and laboratory of the Department of Floriculture and Landscaping, Dr. YS Parmar University of Horticulture and Forestry, Nauni, Solan (HP). The experiment on ten carnation genotypes i.e. 7 mutants, 3 parents viz.; 'Dark Rendezvous', 'Madras' and 'Tempo' was laid out in Randomized Block Design (RBD) under polyhouse conditions. All the mutants developed after the irradiation with gamma rays showed variation in color. In this study, different morphological parameters of the mutants and their parents were recorded. Among different mutants, maximum plant height was recorded in mutant of 'Dark Rendezvous' i.e. 'Rendez-Vous A(2)' (67.70 cm) and maximum flower size in 'Rendez-Vous C-2' (8.40 cm). Duration of flowering was recorded maximum in 'Tempo A(1)' (67.67 days) and vase life in 'Rendez-Vous C-1' (14.79 days). For the majority of the characters analyzed, all mutants performed better in comparison to parents. Moreover, for the characterization of mutants at the molecular level, ten ISSR primers were used and DNA polymorphism was observed with four primers. A total of fifteen polymorphic bands were produced by these four primers. No monomorphic band was observed with any primer resulting in 100% polymorphism. Variations in the plant material can be explained through genetic polymorphism. These results directly strengthen the significance of mutation breeding in developing improved carnation cultivars and substantiate the use of molecular characterization for validating genetic variation. Furthermore, they emphasize the scope for the commercial expansion of carnation cultivation through the selection of promising mutants.

The European Pulsar Timing Array (EPTA) and Indian Pulsar Timing Array (InPTA) collaborations have measured a low-frequency common signal in the combination of their second and first data releases respectively, with the correlation properties of a gravitational wave background (GWB). Such signal may have its origin in a number of physical processes including a cosmic population of inspiralling supermassive black hole binaries (SMBHBs); inflation, phase transitions, cosmic strings and tensor mode generation by non-linear evolution of scalar perturbations in the early Universe; oscillations of the Galactic potential in the presence of ultra-light dark matter (ULDM). At the current stage of emerging evidence, it is impossible to discriminate among the different origins. Therefore, in this paper, we consider each process separately, and investigate the implications of the signal under the hypothesis that it is generated by that specific process. We find that the signal is consistent with a cosmic population of inspiralling SMBHBs, and its relatively high amplitude can be used to place constraints on binary merger timescales and the SMBH-host galaxy scaling relations. If this origin is confirmed, this is the first direct evidence that SMBHBs merge in nature, adding an important observational piece to the puzzle of structure formation and galaxy evolution. As for early Universe processes, the measurement would place tight constraints on the cosmic string tension and on the level of turbulence developed by first-order phase transitions. Other processes would require non-standard scenarios, such as a blue-tilted inflationary spectrum or an excess in the primordial spectrum of scalar perturbations at large wavenumbers. Finally, a ULDM origin of the detected signal is disfavoured, which leads to direct constraints on the abundance of ULDM in our Galaxy.

We present the results of a search for continuous gravitational wave signals (CGWs) in the second data release (DR2) of the European Pulsar Timing Array (EPTA) Collaboration. The most significant candidate event from this search has a gravitational wave frequency of 4-5 nHz. Such a signal could be generated by a supermassive black hole binary (SMBHB) in the local Universe. We present the results of a follow-up analysis of this candidate using both Bayesian and frequentist methods. The Bayesian analysis gives a Bayes factor of 4 in favour of the presence of the CGW over a common uncorrelated noise process. In contrast, the frequentist analysis estimates the p-value of the candidate to be < 1%, also assuming the presence of common uncorrelated red noise. However, comparing a model that includes both a CGW and a gravitational wave background (GWB) to a GWB only, the Bayes factor in favour of the CGW model is only 0.7. Therefore, we cannot conclusively determine the origin of the observed feature, nor can we rule it out as a CGW source. We present results of simulations that demonstrate that data containing a weak gravitational wave background can be misinterpreted as data including a CGW and vice versa, providing two plausible explanations for the EPTA DR2 data. Further investigations combining data from all PTA collaborations will be needed to reveal the true origin of this feature.

The Australian, Chinese, European, Indian, and North American pulsar timing array (PTA) collaborations recently reported, at varying levels, evidence for the presence of a nanohertz gravitational wave background (GWB). Given that each PTA made different choices in modeling their data, we perform a comparison of the GWB and individual pulsar noise parameters across the results reported from the PTAs that constitute the International Pulsar Timing Array (IPTA). We show that despite making different modeling choices, there is no significant difference in the GWB parameters that are measured by the different PTAs, agreeing within $1\sigma$. The pulsar noise parameters are also consistent between different PTAs for the majority of the pulsars included in these analyses. We bridge the differences in modeling choices by adopting a standardized noise model for all pulsars and PTAs, finding that under this model there is a reduction in the tension in the pulsar noise parameters. As part of this reanalysis, we "extended" each PTA's data set by adding extra pulsars that were not timed by that PTA. Under these extensions, we find better constraints on the GWB amplitude and a higher signal-to-noise ratio for the Hellings and Downs correlations. These extensions serve as a prelude to the benefits offered by a full combination of data across all pulsars in the IPTA, i.e., the IPTA's Data Release 3, which will involve not just adding in additional pulsars, but also including data from all three PTAs where any given pulsar is timed by more than as single PTA.

This paper presents high-performance computing efforts with FPGA for the accelerated pulsar/transient search for the square kilometre array (SKA). Case studies are presented from within SKA and pathfinder telescopes highlighting future opportunities. It reviews the scenario that has shifted from offline processing of the radio telescope data to digitizing several hundreds/thousands of antenna outputs over huge bandwidths, forming several hundreds of beams, and processing the data in the SKA real-time pulsar search pipelines. A brief account of the different architectures of the accelerators, primarily, the new generation field programmable gate array-based accelerators, showing their critical roles to achieve high-performance computing and in handling the enormous data volume problems of the SKA is presented here. It also presents power-performance efficiency of this emerging technology and presents potential future scenarios.

We report the discovery of three millisecond pulsars (MSPs): PSRs J1120−3618, J1646−2142, and J1828+0625 with the Giant Metrewave Radio Telescope (GMRT) at a frequency of 322 MHz using a 32 MHz observing bandwidth. These sources were discovered serendipitously while conducting the deep observations to search for millisecond radio pulsations in the directions of unidentified Fermi Large Area Telescope (LAT) γ-ray sources. We also present phase coherent timing models for these MSPs using ∼5 yr of observations with the GMRT. PSR J1120−3618 has a 5.5 ms spin period and is in a binary system with an orbital period of 5.6 days and minimum companion mass of 0.18 M ⊙, PSR J1646−2142 is an isolated object with a spin period of 5.8 ms, and PSR J1828+0625 has a spin period of 3.6 ms and is in a binary system with an orbital period of 77.9 days and minimum companion mass of 0.27 M ⊙. The two binaries have very low orbital eccentricities, in agreement with expectations for MSP-helium white dwarf systems. Using the GMRT 607 MHz receivers having a 32 MHz bandwidth, we have also detected PSR J1646−2142 and PSR J1828+0625, but not PSR J1120−3618. PSR J1646−2142 has a wide profile, with significant evolution between 322 and 607 MHz, whereas PSR J1120−3618 exhibits a single peaked profile at 322 MHz and PSR J1828+0625 exhibits a single peaked profile at both the observing frequencies. These MSPs do not have γ-ray counterparts, indicating that these are not associated with the target Fermi LAT pointing emphasizing the significance of deep blind searches for MSPs.

Dahlia is a popular bulbous ornamental plant being used as bedding plant, pot plant and for cut flowers. Under sub-montane, sub tropical conditions, 24 cultivars of Dahlia variabilis L. were planted in randomized complete block design and their flowering and vegetative growth characters were evaluated and genetic and phenotypic variance were estimated using ANOVA. Phenotypic and genetic coefficients of variation were recorded maximum for leaf area (34.5% and 33.5%) implies that variability is mostly controlled by the genetic component. Heritability (broad sense) was maximum for flowering duration (98.6%) followed by plant height (97.8%). Estimated genetic gain was high for leaf area (66.9%) followed by internodal length (55.2%). Flower number was found positively correlated with plant height, flower stalk length, number of side shoots, plant spread and number of leaves. Path co-efficient analysis showed that stalk length had maximum positive direct effect on number of flowers per plant (2.62) followed by days taken to bud formation (1.13), flowering duration (0.85), number of leaves (0.81), plant spread (0.78) at genetic level. The results suggest that there are sufficient genetic variation available among tested cultivars and can be used for genetic improvement of dahlia.

Context. Globular clusters (GCs) contain a unique pulsar population, with many exotic systems that can form only in their dense stellar environments. Such systems are potentially very interesting for new tests of gravity theories and neutron-star mass measurements. Aims. The leap in sensitivity of the upgraded Giant Metrewave Radio Telescope (uGMRT) in India, especially at low radio frequencies (< 1 GHz), motivated a new search for radio pulsars in a group of eight southern GCs. We aim to image these clusters in order to have independent measurements of the radio fluxes of known pulsars and the identification of bright radio sources that could be pulsars missed by pulsation search pipelines due to their inherent limitations. Methods. The observations were conducted at 650 MHz (Band 4 receivers) on Terzan 5, NGC 6441, NGC 6440, and NGC 6544, and at 400 MHz (Band 3 receivers) on NGC 6652, NGC 6539, NGC 1851, and M 30. Segmented acceleration and jerk searches were performed on the data. Simultaneously, we obtained interferometric data on these clusters, which were later converted into radio images. Results. We discovered PSR J1835−3259B, a 1.83-ms pulsar in NGC 6652; this is in a near-circular wide orbit of 28.7-h with an unidentified low-mass (∼0.2 M⊙) companion, likely a helium white dwarf. We derived a ten-year timing solution for this system. We also present measurements of scattering, flux densities, and spectral indices for some of the previously known pulsars in these GCs. Conclusions. A significant fraction of the pulsars in these clusters have steep spectral indices. Additionally, we detected eight radio point sources not associated with any known pulsar positions in the radio images. There are four newly identified sources, three in NGC 6652 and one in NGC 6539, as well as one previously identified source in NGC 1851, NGC 6440, NGC 6544, and Terzan 5. Surprisingly, our images show that our newly discovered pulsar, PSR J1835−3259B, is the brightest pulsar in all GCs we have imaged; like other pulsars with broad profiles (Terzan 5 C and O), its flux density in the radio images is much larger than in its pulsations. This indicates that their pulsed emission is only a fraction of their total emission. The detection of radio sources outside the core radii but well within the tidal radii of these clusters show that future GC surveys should complement the search analysis by using the imaging capability of interferometers, and preferentially synthesise large number of search beams in order to obtain a larger field of view.

We performed deep observations to search for radio pulsations in the directions of 375 unassociated Fermi Large Area Telescope (LAT) gamma-ray sources using the Giant Metrewave Radio Telescope (GMRT) at 322 and 607 MHz. In this paper we report the discovery of three millisecond pulsars (MSPs), PSR J0248+4230, PSR J1207-5050 and PSR J1536-4948. We conducted follow up timing observations for around 5 years with the GMRT and derived phase coherent timing models for these MSPs. PSR J0248+4230 and J1207-5050 are isolated MSPs having periodicities of 2.60 ms and 4.84 ms. PSR J1536-4948 is a 3.07 ms pulsar in a binary system with orbital period of around 62 days about a companion of minimum mass 0.32 solar mass. We also present multi-frequency pulse profiles of these MSPs from the GMRT observations. PSR J1536-4948 is an MSP with an extremely wide pulse profile having multiple components. Using the radio timing ephemeris we subsequently detected gamma-ray pulsations from these three MSPs, confirming them as the sources powering the gamma-ray emission. For PSR J1536-4948 we performed combined radio-gamma-ray timing using around 11.6 years of gamma-ray pulse times of arrivals (TOAs) along with the radio TOAs. PSR J1536-4948 also shows evidence for pulsed gamma-ray emission out to above 25 GeV, confirming earlier associations of this MSP with a >10 GeV point source. The multi-wavelength pulse profiles of all three MSPs offer challenges to models of radio and gamma-ray emission in pulsar magnetospheres.

We report on the simultaneous Giant Metrewave Radio Telescope (GMRT) and Algonquin Radio Observatory (ARO) observations at 550-750 MHz of the scintillation of PSR B1508+55, resulting in an similar to 10000-km baseline. This regime of measurement lies between the shorter few 100- to 1000-km baselines of earlier multistation observations and the much longer earth-space baselines. We measure a scintillation cross-correlation coefficient of 0.22, offset from zero time lag due to a similar to 45-s traversal time of the scintillation pattern. The scintillation time of 135 s is 3x longer, ruling out isotropic as well as strictly one-dimensional scattering. Hence, the low cross-correlation coefficient is indicative of highly anisotropic but two-dimensional scattering. The common scintillation detected on the baseline is confined to low delays of less than or similar to 1 mu s, suggesting that this correlation may not be associated with the parabolic scintillation arc detected at the GMRT. Detection of pulsed echoes and their direct imaging with the Low-Frequency Array (LOFAR) by a different group enable them to measure a distance of 125 pc to the screen causing these echoes. These previous measurements, alongside our observations, lead us to propose that there are at least two scattering screens: the closer 125-pc screen causing the scintillation arc detected at GMRT, and a screen further beyond causing the scintillation detected on the GMRT-ARO baseline. We advance the hypothesis that the 125-pc screen partially resolves the speckle images on the screen beyond leading to loss of coherence in the scintillation dynamic spectrum to explain the low cross-correlation coefficient.

Water scorpion, Laccotrephes maculatus Fabr. is unisexual and exhibits sexual dimorphism. The males are relatively smaller with conspicuous connexival spines and possess distinct external genitalia. The male reproductive organs include a pair of testis, a pair of vasa deferentia, a pair of vesicula seminalis, two pairs of accessory glands and unpaired median ductus ejaculatorious. The female reproductive organs possess a pair of ovaries, a pair of lateral oviducts, a common oviductus communis, a vagina and the spermatotheca.

We report on the simultaneous Giant Metrewave Radio Telescope (GMRT) and Algonquin Radio Observatory (ARO) observations at 550-750 MHz of the scintillation of PSR B1508+55, resulting in a ∼10,000-km baseline. This regime of measurement lies between the shorter few 100-1000 km baselines of earlier multi-station observations and the much longer earth-space baselines. We measure a scintillation cross-correlation coefficient of 0.22, offset from zero time lag due to a ∼ 45 s traversal time of the scintillation pattern. The scintillation time of 135 s is 3× longer, ruling out isotropic as well as strictly 1D scattering. Hence, the low cross-correlation coefficient is indicative of highly anisotropic but 2D scattering. The common scintillation detected on the baseline is confined to low delays of ≲ 1 μs, suggesting that this correlation may not be associated with the parabolic scintillation arc detected at the GMRT. Detection of pulsed echoes and their direct imaging with the Low Frequency Array (LOFAR) by a different group enable them to measure a distance of 125 pc to the screen causing these echoes. These previous measurements, alongside our observations, lead us to propose that there are at least two scattering screens: the closer 125 pc screen causing the scintillation arc detected at GMRT, and a screen further beyond causing the scintillation detected on the GMRT-ARO baseline. We advance the hypothesis that the 125-pc screen partially resolves the speckle images on the screen beyond leading to loss of coherence in the scintillation dynamic spectrum, to explain the low cross-correlation coefficient.

Context. Pulsar radio emission undergoes dispersion due to the presence of free electrons in the interstellar medium (ISM). The dispersive delay in the arrival time of the pulsar signal changes over time due to the varying ISM electron column density along the line of sight. Accurately correcting for this delay is crucial for the detection of nanohertz gravitational waves using pulsar timing arrays. Aims. We aim to demonstrate the precision in the measurement of the dispersion delay achieved by combining 400−500 MHz (BAND3) wide-band data with those at 1360−1460 MHz (BAND5) observed using the upgraded GMRT, employing two different template alignment methods. Methods. To estimate the high precision dispersion measure (DM), we measure high precision times-of-arrival (ToAs) of pulses using carefully generated templates and the currently available pulsar timing techniques. We use two different methods for aligning the templates across frequency to obtain ToAs over multiple sub-bands and therefrom measure the DMs. We study the effects of these two different methods on the measured DM values in detail. Results. We present in-band and inter-band DM estimates of four pulsars over the timescale of a year using two different template alignment methods. The DMs obtained using both these methods show only subtle differences for PSRs J1713+0747 and J1909−3744. A considerable offset is seen in the DM of PSRs J1939+2134 and J2145−0750 between the two methods. This could be due to the presence of scattering in the former and profile evolution in the latter. We find that both methods are useful but could have a systematic offset between the DMs obtained. Irrespective of the template alignment methods followed, the precision on the DMs obtained is about 10−3 pc cm−3 using only BAND3 and 10−4 pc cm−3 after combining data from BAND3 and BAND5 of the uGMRT. In a particular result, we detected a DM excess of about 5 × 10−3 pc cm−3 on 24 February 2019 for PSR J2145−0750. This excess appears to be due to the interaction region created by fast solar wind from a coronal hole and a coronal mass ejection observed from the Sun on that epoch. A detailed analysis of this interesting event is presented.

FRB 20180916B is a well-studied repeating fast radio burst source. Its proximity (~150 Mpc), along with detailed studies of the bursts, have revealed many clues about its nature -- including a 16.3-day periodicity in its activity. Here we report on the detection of 18 bursts using LOFAR at 110-188 MHz, by far the lowest-frequency detections of any FRB to date. Some bursts are seen down to the lowest-observed frequency of 110 MHz, suggesting that their spectra extend even lower. These observations provide an order-of-magnitude stronger constraint on the optical depth due to free-free absorption in the source's local environment. The absence of circular polarization and nearly flat polarization angle curves are consistent with burst properties seen at 300-1700 MHz. Compared with higher frequencies, the larger burst widths (~40-160 ms at 150 MHz) and lower linear polarization fractions are likely due to scattering. We find ~2-3 rad/m^2 variations in the Faraday rotation measure that may be correlated with the activity cycle of the source. We compare the LOFAR burst arrival times to those of 38 previously published and 22 newly detected bursts from the uGMRT (200-450 MHz) and CHIME/FRB (400-800 MHz). Simultaneous observations show 5 CHIME/FRB bursts when no emission is detected by LOFAR. We find that the burst activity is systematically delayed towards lower frequencies by ~3 days from 600 MHz to 150 MHz. We discuss these results in the context of a model in which FRB 20180916B is an interacting binary system featuring a neutron star and high-mass stellar companion.

Two strains of annual chrysanthemum [Glebionis coronaria (L.) Spach] viz. GC-W (White) and GC-Y (Yellow), as part of their proposed INM schedule were applied with certain organic (Biofertilizers, Jeevamrit) and inorganic fertilizers (NPK) in various combinations. Same observations on various growth and flowering and yield parameters were recorded both the strains in two successive years. Results revealed that growth parameters such as maximum plant height (95.31 cm), plant spread (45.19 cm), flowering parameters such as minimum number of days taken for first flower opening (95.01 days), maximum number of flowers per plant (170.50), individual flower weight (2.30 g), duration of flowering (54.97 days) and yield parameters such as maximum flower yield per plant (490.80 g) were recorded in the plants receiving the treatment of Azotobacter, Phosphate Solubilizing Bacteria (PSB) and 75% recommended dose of fertilizers (20 g N and 10 g P2O5 / m2). Whereas maximum flower size at the time of peak flowering (5.91 cm), was found in the plants supplied with Azotobacter, PSB and 50% RDF. The observed cost benefit ratio in both the strains ranged from 1.92 (GC-W) to 2.00 (GC-Y).

Flower production is considered as a profitable business enterprise and is regarded as a means of socio-economic development in India. The economic importance of floriculture was not considered and it was not practiced commercially but in present times, it has emerged as a profitable venture. The country has tremendous potential when it comes to expanding the floriculture as a profitable business and possesses certain advantages over other flower growing countries like congenial climatic conditions, cheap labour, huge market base and support from the Central and state Govt. Development of advanced technologies in raising ease the life of human beings In spite of all these, the stake holders are experiencing several constraints with respect to production of quality cut flowers in huge quantum including their marketing. Several schemes have been started by the National as well as the State Govt. to promote the commercial flower production among different categories of farmers in the state. In spite of all the assistance provided by the Govt., growers are experiencing certain problems in production International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 9 Number 11 (2020) Journal homepage: http://www.ijcmas.com

Barleria cristata L. ‘Alba’ is a white flowering perennial shrub used as a hedge and specimen plant in landscaping and has potential of being grown as a pot plant too. The study was conducted on this plant to ascertain the effect of benzyl adenine (BA), paclobutrazol with pinching (shoot decapitation) for making it a presentable pot plant. The experiment was laid out in a Completely Randomized Design (Factorial) using three levels of pinching i.e. no pinching(control), single pinching, double pinching with three levels of each BA (drench) and paclobutrazol (foliar spray) i.e. 0 ppm, 100 ppm and 200 ppm each. The results revealed that the double pinched plants coupled with the application of BA @ 200 ppm and paclobutrazol @ 200 ppm had recorded maximum values for number of side shoots per plant (25.00), number of leaves per plant (110.80), number of flower clusters per plant (28.87), number of flowers per cluster (11.07), number of flowers per plant opened at a time (28.93) and duration of flowering (36.33). However, maximum pot presentability score (88.00) was found in those plants which exhibited optimum plant height (28.39 cm) and plant spread (30.81 cm) along with other pot presentability attributes with the application of double pinching, paclobutrazol and BA @ 100 ppm each. In the light of the presentability attributes of the Barleria in the pots, treatment combination of double pinching, BA (100 ppm) and paclobutrazol (100 ppm) found to be most suitable.

Solid waste disposal is major problem in the world, flower waste is an integral part of this Floral waste is one of the major concerns. However, like any other natural solid waste floral waste can we technologically improvised on, converting it to value-added. Degradation otherwise is a very slow process and it causes a massive hazard to wellbeing of our surroundings primarily soil and water. Therefore, there is a need of proper and eco-friendly process for floral waste degradation. Looking into the harmful impact of the improper disposal of wastes on the environment and the slow degradation of these wastes, emphasis should be given on how we can transform this waste to wealth, by their utilisation in diverse sectors, ranging from agriculture to various other industries, creating various value- added products that can help generate livelihood as well.