Genetic and phenotypic variability of yield components in wheat, Triticum aestivum L.

Abstract

The heritability, phenotypic variability and components of variance for spike length and number of spikelets per spike have been studied in 50 cultivars from different selection centers all over the world. The experiment was performed in randomized block design in three replications on the experimental field in two years. A total number of 60 plants have been analyzed in the full maturity stage. Average estimated values of spike length and number of spikelets per spike differed significantly among years and among cultivars. The highest average value of spike length had Mironovskaya 808 cultivar (V =14.5 cm), and the lowest value was found in Etoille de Choisy (J=8.1 cm) and San Pastore cultivar (V =8.2). During investigated periods the highest average value for number of spikelets/spike had Sava cultivar (V=28.2), and the lowest value expressed Frontana cultivar (V =19.2). The average variation coefficient for spike length was 8.0%, and for number of spikelets per spike was 7.5%. The lowest variability for spike length was established in Pernel cultivar (V=4.8%) and the highest in Lepenica cultivar (V=12.9%). The coefficient of variation for number of spikelets per spike ranged from 4.7% in Bankut 1205 to 12.4% in Norin 10 cultivar. The obtained heritability values in broad sense were fairly high for spike length (96.4%) and number of spikelets per spike (79.1%). Phenotypic analysis of variance indicated that genetic variance took a larger portion of the total phenotypic variability for spike length (81.82%) and for number of spikelets per spike (57.36%) than influence of environmental factors on expressing of analyzed yield components

Developing a Selection Criterion for Terminal Heat Tolerance in Bread Wheat Based on Various Mopho-Physiological Traits

“…Thus genetic advance has an added edge over heritability as a guiding factor to breeders in various selection programmes. Genetic advance expressed as a percentage of mean was observed to be high (>50%) for canopy temperature depression (CTD I) and membrane thermostability (Zecevic et al, 2010, Rehman et al, 2016. Genetic advance coupled with high heritability was reported for canopy temperature depression and membrane injury percentage (Kumar et al, 2016;Gowda et al, 2011), which is in conformity with the present findings.…”

“…High heritability estimate was exhibited by membrane thermostability (93.35), NDVI-III (87.10), NDVI-I (8.10) and NDVI-II (85.77). The remaining traits showed moderate levels of heritability (Dwivedi et al, 2003;Atta et al, 2008;Zecevic et al, 2010).…”

“…Genetic advance coupled with high heritability was reported for canopy temperature depression and membrane injury percentage (Kumar et al, 2016;Gowda et al, 2011), which is in conformity with the present findings. Moderate estimate of genetic advance (25%-50%) was reported for number of tillers per plant, NDVI I, CTD (I & II) and spike length, whereas low estimate of genetic advance was reported for rest of the traits like grain yield per plant and 1000 kernel weight (Singh et al, 2008;Tripathi et al, 2015;Zecevic et al, 2010).To predict the reliable estimates of additive or non-additive effects, heritability should be considered in conjugation with genetic advance (Burton 1952, Johnson et al, 1955. High heritability with high genetic advance was found for membrane thermostability indicated the additive effect of genes and selection may be effective for the trait.…”

Effect of Some Preceded Peanut Cultivars on Wheat Yield and Agro – Economic Feasibility Under Two Cropping Systems in Sandy Soil

“…4, No. 2; grain weight per spike is very important yield components, which directly influence to yield and depends on grain number and grain chemical composition (Zecevic et al, 2010).…”

Correlated Response and Path Analysis for Different Characters in F3 Segregating Generation of Wheat (Triticum aestivum Em. Thell. L.)

“…The correlation coefficients become insufficient for using yield components as selection criteria to improve grain yields. It is reasonable to know whether any yield components has a direct or indirect effect on grain yield, so that selection studies can be carried out successfully (Khayatnezhad et al, 2010;Zecevic et al, 2005).…”