66 research outputs found

    Fine mapping of rice drought QTL and study on combined effect of QTL for their physiological parameters under moisture stress condition

    Get PDF
    The present investigation was undertaken to study the effect of different yield QTL (DTY2.2, DTY3.1 and DTY8.1) under drought and their physiological response to drought stress. Backcross Inbred Lines (BILs) of IR64 (CB-193 and CB-229) along with IR64, APO and the traditional rice variety Norungan were raised in green house condition under water stress and control to evaluate the effect of the QTL on grain yield. The BIL CB-193 recorded higher photosynthetic rate (22.051), transpiration rate (7.152) and Ci/Ca ratio (0.597) whereas the BIL CB-229 recorded high relative water content (80.76%). It was found that the combination of three QTL (CB-229) performed better than the susceptible parent and the line with two QTL (CB-193 Fine-mapping of two QTLs viz., qDTY2.2 and qDTY8.1, for grain yield (GY) were conducted using backcross derived lines. Composite interval mapping analyses resolved the originally identified qDTY2.2 region of 6.7 cM into a segment of 2.1 cM and two sub QTLs at region between RM23132 and RM1578 (75.75 cM- 77.66 cM), RM515 and RM1578 (75.11 cM-77.66 cM) were identified in qDTY8.1 region. However this study provides a unique opportunity to breeders to introgress such regions together as a unit into high-yielding drought-susceptible varieties through MAS

    Assessment of variability parameters and diversity of panicle architectural traits associated with yield in rice (Oryza sativa L.)

    Get PDF
    The rice panicle, a pivotal reproductive structure, signifies the transition from vegetative to reproductive growth in plants. Comprising components such as the rachis, primary and secondary branches, seed quantities and branch lengths, panicle architecture profoundly influences grain production. This study delves into the diversity of panicle architecture traits and scrutinizes variability parameters across 69 distinct rice genotypes. Our findings underscore substantial variations in panicle architecture traits among genotypes. Particularly noteworthy are traits with the highest coefficient of variation (CV%), encompassing the count of secondary branches, single plant yield, productive tillers per plant, seeds per secondary branch and panicle weight. Correlation analysis reveals robust positive connections between panicle weight, the number of filled grains per panicle, 1000-grain weight and single plant yield. The number of secondary branches exhibits the most substantial phenotypic coefficient of variation (PCV%) at 47.14%, accompanied by a genotypic coefficient of variation (GCV%) of 43.57%. Traits such as days to 50% flowering, plant height and number of filled grains per panicle manifest high heritability (97.04%, 91.24% and 76.22% respectively) and notable genetic advancement (23.11%, 39.62% and 47.49%). The principal component analysis identifies the primary component (PC1) as the principal contributor to variance. Biplot analysis accentuates positive correlations between attributes like the number of filled grains per panicle, panicle length, plant height, primary branch count, panicle weight, seeds per primary branch and the number of secondary branches with single plant yield. By employing Mahalanobis D2 statistics, the classification of genotypes into 6 distinct clusters reveals clusters III and IV as distinguished by their significant inter-cluster and intra-cluster distances. This comprehensive analysis unveils the potential for harnessing panicle architecture traits to enhance grain production and advances our comprehension of intricate relationships within diverse rice genotypes

    Corporate Social Responsibility Strategies of Spanish Listed Firms and Controlling Shareholders’ Representatives

    Get PDF
    This article aims at analyzing how controlling shareholders’ representatives on boards affect corporate social responsibility (CSR) strategies (disclosing CSR matters) in Spain, a context characterized by high ownership concentration, one-tier boards, little board independence, weak legal protection for investors, and the presence of large shareholders, especially institutional shareholders. Furthermore, among controlling shareholders’ representatives, we can distinguish between those appointed by insurance companies and banks and those appointed by mutual funds, investment funds, and pension funds. The effect of these categories of directors on CSR strategies is, therefore, also analyzed. Our findings suggest that controlling shareholders’ representatives have a positive effect on CSR strategies, as do directors appointed by investment funds, pension funds, and mutual funds, while directors appointed by banks and insurance companies have no impact on CSR strategies. This analysis offers new insights into the role played by certain types of directors on CSR strategies

    Neurilemmoma of the orbit - a case report

    No full text

    Phytochemical analysis, synthesis, antitumor and antimicrobial activity of Silver Nanoparticles using flower extracts of Ixora coccinea

    No full text
    Abstract: This study aims to analyse aqueous, ethanolic and methanolic extracts of flowers of Ixora coccinea for the presence of various phytochemicals and synthesised silver nanoparticles using the aqueous extract of Ixora coccinea flowers and also checked the antimicrobial activity, TLC studies using both the extracts. The presence of various phytochemicals viz., alkaloids, tannins, carbohydrates, flavonoids, terpenes and glycosides were analysed by standard biochemical screening methods. The synthesised silver nanoparticles (SNPs) were characterised by using UV-Vis Spectroscopy, FTIR, XRD, SEM, TEM The synthesised nanoparticles were found to be spherical in shape with average size in the range of 5-10 nm and also showed inhibitory zones to the bacterial cultures. The results revealed that the aqueous extract of Ixora coccinea flowers is a very good bioreductant for the synthesis of silver nanoparticles

    Not Available

    No full text
    Not AvailableOne of priority research area in rice is identification of suitable genotypes for rain fed condition. Quantifying the drought tolerance genotypes was done with different stress indices obtained from the yield data under severe drought and irrigated condition with four backcross inbred lines derived from the cross between IR64 (drought susceptible) and Apo (drought tolerant) which carried three mega QTL in different combination of classes namely qDTY2.2, qDTY3.1 and qDTY8.1. The genotype CB 229 is the highly tolerant one confirmed by tolerant and susceptible indices, which had three DTY QTL (qDTY2.2, qDTY3.1 and qDTY8.1) combinations maximizes the yield in drought condition. Among the selection indices, YI, MPI, DRI, STI, HM, GMP, MRP and RE are the best indices to identify tolerant genotype. Clustering based on principal component analysis exhibits that CB 229, CB 193-2 and CB 193-3 falls on the quarter where tolerant indices found. Overall study shows that the selection based on stress indices may be rewarded to identify superior genotypes under severe drought condition.Not Availabl

    Not Available

    No full text
    Not AvailableAmong the abiotic stresses, drought is the major factor for heavy yield losses in rice production. The present study was undertaken with an aim of understanding the effect of mega QTLs of Apo controlling yield under drought. The BILs viz., CB 229 and CB 193-3 were evaluated for their drought responses under green house conditions along with the parents Apo, IR64 and check Norungan during Summer 2015, Kharif 2015, Rabi 2015-16. The results from this study reported that, Apo and BILs had higher photosynthetic rate when compared to IR64 under drought. CB 229 had low reduction per cent of photosynthesis (45.25%), Ci/Ca (23.88%), conductance (52.38%) and RWC (25.72%) compared to susceptible parent IR64. Number of filled grains was much higher in Apo, CB229 and CB 193-3 when compared to IR64 under stress condition. The significant reduction in single plant yield under moisture stress condition was observed in all the genotypes especially in IR64 (65.15%). Reduction was relatively less in the donor Apo and BILs. CB 229 showed a greater RWC, conductance, moderate transpiration rate, increased water uptake, a higher assimilation rate and a higher grain yield under the moisture stress condition compared to the other BIL and IR64. It was found that CB 229 with three QTL, i.e., qDTY2.2, qDTY3.1 and qDTY8.1, showed better performance than CB 193-3 with two QTL, qDTY3.1 and qDTY8.1, under severe stress while in irrigated condition CB 229 was onpar with IR64.Not Availabl
    • 

    corecore