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The present investigation was conducted during kharif 2021 in paddy growing regions of Northern Karnataka. Pooled analysis of variance across locations, showed significant difference for all the traits selected except days to 50 percent flowering and grain length for GxE source of variation. Eberhart and Russel stability model was used to identify the stable performing genotypes for particular trait across the diverse environments. Out of 21 genotypes evaluated two genotypes (MAS-26 and MAS-946) were high performing but not consistent in their performance for yield and yield attributing traits across the diverse environments. The genotypes CR Dhan-201, Indrani, CR Dhan-206 were found to be the most stable genotypes across evaluated climatic conditions for grain yield in Northern parts of Karnataka. [ABSTRACT FROM AUTHOR]

Two biologically active classes of compounds coumarins and triazoles were employed to form the Schiff bases. The synthesized Schiff base viz., 3-aryl-[(1-isocyano-4-methyl-7-hydroxycoumarin)]-5-methyl-1,3,4-triazoline-2-one and its substituents were obtained by the condensation of amino group of mono and disubstituted derivatives of 3-methyl-5-oxo-1,2, 4-triazoles with 8-formyl-7-hydroxy-4-methylcoumarin in alcohol. The characterization were studied by elemental analysis, IR, 1H NMR and mass spectra. The biological activities of the compounds were assayed against two bacterial via, B. subtilis, E.coli and two fungal strains A. niger, C.albican. The results indicate that the present compounds may serve as better fungicides when compared to bactericides. The synthesized compounds have turned to be wonder compounds possessing antimicrobial properties. [ABSTRACT FROM AUTHOR]

Wheat is one of major cereal crops with paramount importance that is cultivated across the globe. Fusarium head blight (FHB) is a catastrophic disease of wheat which has recently risen to prominence due to its direct impact on the quality and quantity of wheat on a global scale. During a field survey conducted in Rabi 2021-22, wheat spikes showing characteristic symptoms of head blight were observed in northern parts of the Karnataka, India, in the districts Bagalkote, Belagavi and Dharwad. The infected spikelets from the heads with symptoms of infection were washed well in distilled water and surface sterilized using 1% sodium hypochlorite solution. They were further washed using sterilized distilled water to remove the traces of sodium hypochlorite. These spikelets were then transferred to sterile potato dextrose agar (PDA) plates under aseptic conditions. The plates were incubated at a temperature of 27±1°C for ten days to obtain good fungal growth. The fungus produced white to orangish pink, dense mycelia and hyaline septate hyphae. Macroconidia were sickle-shaped measuring 35.7 to 52.6 x 3.2 to 5.1 µm, dorsoventrally curved with an elongated basal cell ending in a prominent long foot; the apical cell was also elongated, tapered, slightly curved. Spores had 3 to 4 cells and formed on monophialide. Microconidia and chlamydospores were present only in a few isolates. Fungal genomic DNA was extracted from all the established isolates using CTAB (Cetyl-trimethyl ammonium bromide) method (Murray and Thompson, 1980). The ITS region of r-DNA and translation elongation factor-1 alpha ( TEF-1α ) genes of the ten isolates were amplified using ITS1/ITS4 primer pair (White et al. 1990) and the species-specific EF1F/EF1R primer pair (O'Donnell et al., 1998) respectively, to detect and distinguish within Fusarium species. The results exhibited 95% similarity with Fusarium poae with GenBank Accession No. XMO44849482.1. which was previously reported as a causal agent of Fusarium head blight of wheat in Georgia, USA. The TEF1-α sequences were deposited in the GenBank and the accession numbers from OP716756 to OP716765 were obtained. For the pathogenicity test, spore suspension containing a load of 10 8 conidia ml -1 was prepared from ten days old Fusarium poae culture and sprayed on the healthy wheat heads of the susceptible variety UAS-304 during anthesis stage by using hand atomizer. Control plants were sprayed in a similar manner with sterile distilled water. In order to enhance disease development and increase the accuracy of the evaluation, humidity was maintained for 72 hours post-inoculation period by covering each spike with a plastic bag and misting at least once daily. The characteristic head blight symptoms were observed in the inoculated wheat spikes. No symptoms were noticed in the water-treated control. The plants initially showed bleaching in single spikelet after seven days of inoculation, which eventually spread to the entire spike. After fourteen days of inoculation, the spikes showed blighted appearance with pinkish or orangish mass of mycelia grown on the affected region. The pathogen was further reisolated from the infected plants and examined under the microscope. The similar morphological features as that of the originally inoculated pathogen was observed, hence fulfilling Koch's postulates. To our knowledge, this is the first report of Fusarium poae causing head blight of wheat in India. Keeping the current climate change scenario in view, the plausibility of this pathogen causing a major havoc in the near future must not be ignored, considering the fact that it has a wide host range and highly evolving nature. The ubiquity of the Fusarium head blight recently in northern parts of Karnataka urges the need to conduct further studies on the variability, distribution and management of the pathogen.