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The present study was carried out in Kashmir (India) to assess the genetic variability for grain yield and component traits among 14 red rice ecotypes from temperate region (locally known as Zag for its coloured kernels) and correlation and path coefficients were also studied for fifteen agro-morphological characters. Genotypic and phenotypic coefficients of variation were high for grain yield, secondary branches per panicle and panicle weight; moderate for grain number per panicle, grain length:breadth (L:B) ratio and panicle density. High heritability accompanied by high to moderate genetic advance for panicle density, days to 50% flowering, plant height, grain number indicated the predominance of additive gene action for the expression of these characters. Grain yield was found to be positively and significantly correlated with number of tiller per plant, panicle density m-2 and number of grain per panicle at both genotypic and phenotypic levels indicating the importance of these characters for yield improvement in this material. The results of genotypic path analysis revealed that panicle density had the highest positive direct effect followed by plant height and days to flower. The overall results indicated that selection favouring higher panicle density, test weight and panicle weight and medium plant height with a reasonable balance for moderate grain number would help to achieve higher grain yield in this population of red rice ecotypes.

The present study was carried out in Kashmir (India) to assess the genetic variability for grain yield and component traits among 14 red rice ecotypes from temperate region (locally known as Zag for its coloured kernels) and correlation and path coefficients were also studied for fifteen agro-morphological characters. Genotypic and phenotypic coefficients of variation were high for grain yield, secondary branches per panicle and panicle weight; moderate for grain number per panicle, grain length:breadth (L:B) ratio and panicle density. High heritability accompanied by high to moderate genetic advance for panicle density, days to 50% flowering, plant height, grain number indicated the predominance of additive gene action for the expression of these characters. Grain yield was found to be positively and significantly correlated with number of tiller per plant, panicle density m-2 and number of grain per panicle at both genotypic and phenotypic levels indicating the importance of these characters for yield improvement in this material. The results of genotypic path analysis revealed that panicle density had the highest positive direct effect followed by plant height and days to flower. The overall results indicated that selection favouring higher panicle density, test weight and panicle weight and medium plant height with a reasonable balance for moderate grain number would help to achieve higher grain yield in this population of red rice ecotypes.

The F3 population of eighteen different cross combinations using five local and seven exotic genotypes was used to study the genetic parameters, heritability, correlation and path coefficients for fourteen quantitative characters under temperate conditions. The selected progenies showed highly significant difference for most of the agro-morphological characters. Comparatively high phenotypic coefficients of variation were observed for all the character than genotypic coefficient variation. High heritability (%) was recorded for days to 50% flowering (96%) followed by days to maturity (95%) and grain yield per plant (84%). High genetic advance were observed for grain yield (47%) followed by biological yield/plant (27%) and harvest index (25%). Days to 50% flowering was positively and significantly correlated with days to maturity, grain length with LB ratio flag leaf length with grain breadth and panicle length with grain breadth at genotypic level. Path coefficient analysis revealed that harvest index and biological yield has highest direct effect on yield followed by days to maturity and number of grain per panicle. Biological yield per plant has highest indirect effect on yield via days to flowering followed by grain weight via biological yield per plant, grain breadth via days to 50 % flowering and flag leaf length via biological yield per plant. Therefore, information on the genetic parameters such as coefficient of variation, heritability, genetic advance and the influence of environment on the expression of these characters will help the breeder to evolve suitable cultivars within a short time for hill ecologies.

The F3 population of eighteen different cross combinations using five local and seven exotic genotypes was used to study the genetic parameters, heritability, correlation and path coefficients for fourteen quantitative characters under temperate conditions. The selected progenies showed highly significant difference for most of the agro-morphological characters. Comparatively high phenotypic coefficients of variation were observed for all the character than genotypic coefficient variation. High heritability (%) was recorded for days to 50% flowering (96%) followed by days to maturity (95%) and grain yield per plant (84%). High genetic advance were observed for grain yield (47%) followed by biological yield/plant (27%) and harvest index (25%). Days to 50% flowering was positively and significantly correlated with days to maturity, grain length with LB ratio flag leaf length with grain breadth and panicle length with grain breadth at genotypic level. Path coefficient analysis revealed that harvest index and biological yield has highest direct effect on yield followed by days to maturity and number of grain per panicle. Biological yield per plant has highest indirect effect on yield via days to flowering followed by grain weight via biological yield per plant, grain breadth via days to 50 % flowering and flag leaf length via biological yield per plant. Therefore, information on the genetic parameters such as coefficient of variation, heritability, genetic advance and the influence of environment on the expression of these characters will help the breeder to evolve suitable cultivars within a short time for hill ecologies.

Curie temperature of polycrystalline barium hexaferrite (BaFe12O19), prepared by conventional solid state technique, is anomalously and significantly enhanced (by nearly 15%) by energetic heavy ion irradiation (150 MeV, Ag12+) at ambient temperature due to dense electronic excitations Moderate fluence (1 × 1012 ions/cm2) induces structural defects giving rise to above enhancement. As established by X-ray diffraction, scanning electron microscopy and Raman studies, higher fluence (1 × 1013 ions/cm2) has structurally transformed the sample to amorphous phase with marginal change in magnetization and Curie temperature.

Analysis of variance for 11 traits under investigation revealed significant variability among the genotypes. This indicated an extensive range of genetic variability existed among the genotypes of blackgram. On the basis of higher mean performance than general mean, genotype PU-19 reported higher seed yield/plant along with higher number of seeds/pod, number of clusters/plant, number of pods/ cluster. Hence, recommended for the enhancement of area under this variety particular in rainfed ecology. On pooled basis seed yield/plant had significant correlation with all yield contributors except plant height. Number of seeds/pod, number of clusters/plant, number of pods/cluster and seed yield/plant signified high heritability as well as high genetic advance as percentage of mean indicated the presence of additive gene action, while plant height and number of pods/ plant exhibited modest heritability as well as modest genetic advance as percentage of mean. Consequently, suggesting the presence of additive gene action and phenotypic selection for such traits may be useful in the future of blackgram improvement programs.