27 research outputs found

    Genetic Variability and Heritability for Growth and Yield in Cucumber (Cucumis sativus L.)

    Get PDF
    Quantification of variability is the most essential pre-breeding tool in any crop improvement programme. The present investigation was carried out to assess variability existing in twenty four diverse cucumber genotypes. Results revealed high phenotypic and genotypic coefficient of variation for yield per plant, fruit flesh thickness, number of fruits per plant, number of nodes per plant, number of branches per plant, average fruit weight, internode length and vine length. High heritability, coupled with high genetic advance as per cent mean, was recorded for all the characters studied except days to first female-flower opening, days to 50% flowering and days to first-fruit harvest, indicating a scope for improvement through selection

    Biochemical characterization of defense responses in rose genotypes in response to artificial inoculation with black spot pathogen Diplocarpon rosae

    Get PDF
    Resistance responses in the leaves of eight rose genotypes, Knock Out (highly resistant), Arka Nishkant (moderately resistant), R. multiflora (highly susceptible), Arka Swadesh (highly susceptible), IIHRR 13-4 (susceptible), Arka Parimala (susceptible), R. indica (susceptible) and IIHRR 4-15-12 (moderately susceptible), exhibiting varied levels of resistance against black spot were investigated post artificial inoculation with black spot pathogen, Diplocarpon rosae. There was consistent increase in the activities of defense related enzymes such as catalase, peroxidase, polyphenol oxidase, superoxide dismutase and phenylalanine ammonia lyase and other defense related secondary metabolites like phenols and flavonoids at different phases of black spot progression and increase was high in resistant genotypes Knock Out and Arka Nishkant. The peak activity of defense enzymes and high concentration of other metabolites was witnessed during early stages of infection in the resistant genotypes while it was during later phase in the susceptible genotypes. These results suggested that the faster and stronger activation of defense system is associated with the resistance against black spotin the rose genotypes

    Efficacy of Major Plant Extracts/Molecules on Field Insect Pests

    Get PDF
    Insect pests are considered the major hurdle in enhancing the production and productivity of any farming system. The use of conventional synthetic pesticides has led to the emergence of pesticide-resistant insects, environmental pollution, and negative effects on natural enemies, which have caused an ecological imbalance of the predator-prey ratio and human health hazards; therefore, eco-friendly alternative strategies are required. The plant kingdom, a rich repertoire of secondary metabolites, can be tapped as an alternative for insect pest management strategies. A number of plants have been documented to have insecticidal properties against various orders of insects in vitro by acting as antifeedants, repellents, sterilant and oviposition deterrents, etc. However, only a few plant compounds are applicable at the field level or presently commercialised. Here, we have provided an overview of the broad-spectrum insecticidal activity of plant compounds from neem, Annona, Pongamia, and Jatropha. Additionally, the impact of medicinal plants, herbs, spices, and essential oils has been reviewed briefl

    Identification and characterization of Tobacco streak virus, as a new causative agent of necrosis disease of Anthurium

    No full text
    194-200Tobacco streak virus (TSV) was detected from Anthurium samples collected from Anthurium variety Medioria Red from College of Horticulture, Bangalore, India grown under polyhouse cultivation. Sap inoculation of the samples expressing positive reaction through direct antigen coating-enzyme linked immunosorbant assay (DAC-ELISA) produced both localized and systemic infection. The localized infection produced circular necrotic lesions on the leaves of cowpea cv. C152 plants. The samples were also confirmed through dot blot immunibinding assay (DIBA), which showed positive reaction by producing circular, purple coloured spot against TSV specific antibody. Further molecular characterization of TSV through RT-PCR with coat protein gene specific primers produced amplicon size of 929 bp pertaining to RNA3 region. The basic local alignment search tool (BLAST) analysis of coat protein gene through National Centre for Biotechnology Information (NCBI) database had nucleotide and amino acid sequence similarity of 97.6 to 98.8 % and 94.9 to 97.4 %, respectively with known strains of TSV from India. Phylogenetic analysis of the nucleotide sequences Confirmed the Anthurium strain of TSV forms single subgroup with other crop of Indian isolates. This study provides important clues about spread of TSV. To the best of our knowledge it is the first detailed study of TSV infecting Anthurium

    Not Available

    No full text
    Not AvailableABSTRACT Quantification of variability is the most essential pre-breeding tool in any crop improvement programme. The present investigation was carried out to assess variability existing in twenty four diverse cucumber genotypes. Results revealed high phenotypic and genotypic coefficient of variation for yield per plant, fruit flesh thickness, number of fruits per plant, number of nodes per plant, number of branches per plant, average fruit weight, internode length and vine length. High heritability, coupled with high genetic advance as per cent mean, was recorded for all the characters studied except days to first female-flower opening, days to 50% flowering and days to first-fruit harvest, indicating a scope for improvement through selection.Not Availabl

    Not Available

    No full text
    Not AvailableThe Study was conducted to assess the variations in relative susceptibility levels among the populations of diamondback moth in major cabbage growing areas of South Karnataka. The LC50 values were varied across insecticides for single population and also across the populations of geographical locations. The LC50value of Bengaluru, Kolar and Chikkaballapura populations recorded highest for dichlorvos 76 EC (15.63, 31.82 and 22.51 ÎŒg a.i. ml-1) and the lowest LC50value of Bengaluru, Kolar and Chikkaballapura populations recorded for emamectin benzoate 5 SG (3.13 ÎŒg a.i. ml-1), cyantraniliprole 10.26 OD (4.48 ÎŒg a.i. ml-1) and Spinosad 45 SC (2.48 ÎŒg a.i. ml-1) was found to be highly toxic to the third instar larvae of P. xylostella. This clearly indicated that the rate of evolution of resistance in P. xylostella was varied across insecticides and also across geographical locations.Not Availabl

    Exploitation of Hybrid Vigour and Combining Ability Studies for Yield and Its Attributing Traits in Ridge Gourd [Luffa acutangula (Roxb.) L.]

    Get PDF
    Twelve parental lines (7 lines and 5 testers) were crossed in Line × Tester mating design and 35 F1 hybrids of ridge gourd obtained and were studied to investigate the extent of heterosis and combining ability for yield and related traits. Result revealed that the crosses, COHB-1 × Deepthi (25.95 %), COHB-33 × Deepthi (11.07 %) and COHB-32 × Pusa Nutan (5.09 %) exhibited maximum and significant positive heterosis over the commercial check (Naga) for fruit yield per vine. Among the parents, maximum and significant gca effects was recorded in the line COHB-33 (0.66) followed by Pusa Nutan (0.60) and Deepthi (0.44) for fruit yield per vine. The maximum sca effects was observed in the cross COHB-1 × Deepthi (1.64) followed by COHB-32 × Arka Sumeet (1.12) and COHB-32 × Pusa Nutan (1.03)

    Studies on floral morphology in different genotypes of Jasminum sambac

    No full text
    Not AvailableThe present investigation was undertaken to study the floral morphology behavior among 22 genotypes of Jasminum sambac. Results revealed that among the different genotypes, cluster bearing habit in terminal position was recorded in genotypes Iruvatchi and IIHR JS - 5, whereas other genotypes recorded forked cymes of cluster flowers in terminal and axillary. Three different shapes of flower bud was recorded among the genotypes, viz. pointed and long, pointed and short, rounded and short. Flower bud colour and colour on flower bud opening was white (155 B or 155 C) and pink tinge on flower bud was recorded in IIHR JS - 5. Star and round shaped flower was observed among different genotypes. Three different types of flowers were recorded, viz., single, double and multi-whorled (3 to 6). Among 22 genotypes, Arka Aradhana recorded longest bud (3.85 cm) and corolla (2.11 cm). The genotype IIHR JS - 5 recorded the longest corolla tube (2.29 cm) and Iruvatchi recorded maximum number of forks per cyme (14). Maximum number of calyx lobe was recorded in Gundumallige (8.79 cm), whereas longest calyx lobe was recorded in Soojimalli (1.49 cm). Bigger size of flower was recorded in Soojimalli (4.64 cm) and maximum number of petals was observed in IIHR JS - 1 (40). The information generated on floral morphological traits in different genotypes will facilitate the planned crop improvement programmes in jasmine.Not Availabl

    Transcriptional Responses of the Bdtf1-Deletion Mutant to the Phytoalexin Brassinin in the Necrotrophic Fungus Alternaria brassicicola

    No full text
    Brassica species produce the antifungal indolyl compounds brassinin and its derivatives, during microbial infection. The fungal pathogen Alternaria brassicicola detoxifies brassinin and possibly its derivatives. This ability is an important property for the successful infection of brassicaceous plants. Previously, we identified a transcription factor, Bdtf1, essential for the detoxification of brassinin and full virulence. To discover genes that encode putative brassinin-digesting enzymes, we compared gene expression profiles between a mutant strain of the transcription factor and wild-type A. brassicicola under two different experimental conditions. A total of 170 and 388 genes were expressed at higher levels in the mutants than the wild type during the infection of host plants and saprophytic growth in the presence of brassinin, respectively. In contrast, 93 and 560 genes were expressed, respectively, at lower levels in the mutant than the wild type under the two conditions. Fifteen of these genes were expressed at lower levels in the mutant than in the wild type under both conditions. These genes were assumed to be important for the detoxification of brassinin and included Bdtf1 and 10 putative enzymes. This list of genes provides a resource for the discovery of enzyme-coding genes important in the chemical modification of brassinin
    corecore