Genetic variance and heritability estimation of hybridized pepper plants (Capsicum annuum L.) F2 progeny for begomovirus resistance in growth stage

Pepper is widely cultivated as a condiment and cash crop in Indonesia. However, Pepper yellow leaf curl disease (PepYLCD) caused by begomovirus is currently seriously affect the domestic pepper production. Breeding for begomovirus resistance material by crossing is currently necessary to overcome the constraint. The present study is aimed to determine the resistance of pepper (C. annuum) plants F2 progenies to begomovirus infection in the growth stage. Two local C. annuum accessions, BaPep-5 as a resistance donor for pepy-1 begomovirus resistance gene (locally called Perintis) and BaPep-4 as a susceptible parent (locally called Kencana) were crossed to generate F2 progenies. The research was conducted in Agricultural Extension Training Centre (BLPP) Saree and Horticulture Laboratory of Syiah Kuala University from February to July 2020. 500 F2 progenies were transplanted to the field along with 15 plants of each parent as control. The result suggested that plant height and crown width had the highest broad sense heritability value, whereas the dichotomous height, stem diameter, secondary branch, and tertiary branch had the lowest broad sense heritability value. Coefficient of genetic variance and coefficient of phenotypic variance from overall characteristics were relatively low which suggest the narrow sense to slightly narrow sense heritability.

Lens fluorescence and skin fluorescence in the Copenhagen Twin Cohort Eye Study: Covariates and heritability

Lens and skin fluorescence are related to the systemic accumulation of advanced glycation end products, which is accelerated in diabetes. We have examined lens fluorescence and skin fluorescence in healthy adult twins. The study enrolled twins aged median 59 years from a national population-based registry. Diabetic individuals were excluded from analysis. The interrelatedness between fluorescence parameters and relations between fluorescence and age, current HbA1c and smoking pack years were examined using correlation tests and mixed model linear regression analyses. Broad-sense heritability was analyzed and compared for lens fluorescence, skin fluorescence and HbA1c. Lens fluorescence and skin fluorescence were crudely interrelated (R = 0.38). In linear regression analyses, age explained a larger fraction of the variance in lens fluorescence (R2 = 32%) than in skin fluorescence (R2 = 20%), whereas HbA1c explained smaller variance fractions (R2 = 3% and 8%, respectively) followed by smoking pack years (4% and 3%, respectively). In multivariate analyses, age, HbA1c and smoking pack years combined explained more of the variance in lens fluorescence (R2 = 35%) than in skin fluorescence (R2 = 21%), but the influence of HbA1c on lens fluorescence was not statistically significant (p = .2). Age-adjusted broad-sense heritability was 85% for lens fluorescence, 53% for skin fluorescence and 71% for HbA1c in best fitting heritability models. Both fluorescence parameters increased with age, current glycemia and cumulative smoking. Lens fluorescence was found to be a predominantly heritable trait, whereas skin fluorescence was more influenced by environmental factors and closer related to current glycemia. The results suggest that skin fluorophores have a faster turn-over than lens fluorophores.

High Heritability of Glycyrrhizic Acid, Glabridin, Liquiritin and Liquiritigenin in Licorice (Glycyrrhiza Glabra L.) Populations of Iran

Glycyrrhiza glabra L. is an herbaceous, perennial plant with high distribution in Iran. Genetic variability, heritability and correlation among characters in 22 populations of G. glabra L. were studied. The genetic parameters among the traits including phenotypic variances, genotypic variances, genotype by environment variances, broad-sense heritability and genotypic and phenotypic correlation coefficients were studied. Variance components analysis showed that the extent of phenotypic coefficient of variation (PCV) was fairly higher for all the examined traits compared with genotypic coefficient of variation (GCV). Glabridin (GLA) exhibited high GCV and PCV (156.07% and 156.68%, respectively). The broad sense heritability varied from 38.92–99.79% and narrow sense heritability ranged from 9.70 % to 24.94%. Heritability of GLA, glycyrrhizic acid (GLY), liquiritin (LI), liquiritigenin (LIQ), rutin (RU) and rosmarinic acid (RA) were very high, exhibiting more than 97% heritability. Therefore, these critical characteristics can efficiently be selected and inherited in breeding programs. In most traits, the genotypic correlations showed the same direction as the phenotypic correlations. The contents of GLA and LIQ showed a positive correlation with majority of morphological traits. Therefore, selecting individual plants having desired morphological traits can be correlated with high contents of bioactive compounds in the harvested root.

Estimating genetic variability, gene effect, heritability, and genetic advance of yield component agronomic traits: towards the improvement of peanut agronomic traits.

Background: Peanut is an important oil and legume food crop for human and feed for livestock. Peanut yield association characters like pod and seed traits are the most widely targeted parameter. Peanut yield is a function of growth rate, duration of reproductive growth, and the fraction of crop growth rate which are partitioned toward pod yield. For effective selection, heritability along with genetic advance is more useful than the estimation of only heritability. Methods: The present study field design was laid out using single row and single plot techniques. Pod length, pod width, pod length by width, seed length, seed width, seed length by width yield contributing data were collected both from two parents and 251 RIL populations across two locations in two consecutive cropping seasons (2015/2016 & 2016/2017). Data analysis was computed through SAS ver.9.4 and PBTools ver.1.4. Results: The highest genotypic coefficient of variation was found in pod length (22.47), number of pods per plant (23.66), pod yield per plant (28.43), multiple seedpods per plant (30.44). The highest narrow sense heritability was found in seed length (66%), pod length by width (87%), and pod thickness (93%), meanwhile, the highest broad sense heritability values have been recorded in seed length (99%), seed length by width (99%), number of pods per plant (95%), shelling percentage (94%), pod thickness (93%), thickness of pod shells (92), seed yield per plant (89%), seed thickness (87%), seed width (83%), multiple seedpods per plant (79%), and pod weight per plant (75%). The highest genetic advance as percent of mean values occurred in multiple seedpods per plant (215.44), number of pods per plant (85.28), pod yield per plant (64.90), seed yield per plant (63.49), thickness of pod shells (56.87), pod length by width (36.55), seed length by width (30.98), and seed length (23.26). Conclusions: Additive gene effects were observed in the traits of seed length, seed length by width, pod length, pod width, pod length by width, pod thickness, thickness of pod shells, and multiple seedpods per plant. The highest broad sense heritability values coupled with high genetic gain were estimated in multiple seedpods per plant, number of pods per plant, pod weight plant, seed weight per plant, thickness of pod shells, pod length by width, seed length by width. Therefore, in the present study, use more pod and seed-related traits than the previous findings.

Accurate determination of genotypic variance of cell wall characteristics of a Populus trichocarpa pedigree using high-throughput pyrolysis-molecular beam mass spectrometry

Background Pyrolysis-molecular beam mass spectrometry (py-MBMS) analysis of a pedigree of Populus trichocarpa was performed to study the phenotypic plasticity and heritability of lignin content and lignin monomer composition. Instrumental and microspatial environmental variability were observed in the spectral features and corrected to reveal underlying genetic variance of biomass composition. Results Lignin-derived ions (including m/z 124, 154, 168, 194, 210 and others) were highly impacted by microspatial environmental variation which demonstrates phenotypic plasticity of lignin composition in Populus trichocarpa biomass. Broad-sense heritability of lignin composition after correcting for microspatial and instrumental variation was determined to be H2 = 0.56 based on py-MBMS ions known to derive from lignin. Heritability of lignin monomeric syringyl/guaiacyl ratio (S/G) was H2 = 0.81. Broad-sense heritability was also high (up to H2 = 0.79) for ions derived from other components of the biomass including phenolics (e.g., salicylates) and C5 sugars (e.g., xylose). Lignin and phenolic ion abundances were primarily driven by maternal effects, and paternal effects were either similar or stronger for the most heritable carbohydrate-derived ions. Conclusions We have shown that many biopolymer-derived ions from py-MBMS show substantial phenotypic plasticity in response to microenvironmental variation in plantations. Nevertheless, broad-sense heritability for biomass composition can be quite high after correcting for spatial environmental variation. This work outlines the importance in accounting for instrumental and microspatial environmental variation in biomass composition data for applications in heritability measurements and genomic selection for breeding poplar for renewable fuels and materials.

Agronomic characters, genetic and phenotypic diversity coefficients, and heritability of 12 genotypes of rice

Kartahadimaja J, Utomo SD, Yuliadi E, Salam AK, Warsono, Wahyudi A. 2021. Agronomic characters, genetic and phenotypic diversity coefficients, and heritability of 12 genotypes of rice. Biodiversitas 22: 1091-1097. The achievement of national rice production is always below the target. One of the causes is the low productivity of the varieties grown due to the stagnant genetic capacity of these varieties. The assembly of new lines through breeding is one solution that can increase the genetic capacity of new varieties. Genetic diversity is one of the factors that influence the success of plant breeding. Ten new F9 rice lines were successfully assembled showing various phenotypes. The identification of the specific advantages of each of these new rice lines was based largely on the phenotypic response. The research objective was to identify the genetic advantages of each line through the analysis approach of genetic diversity coefficient (GDC), Phenotific Diversity Coefficient (PDC), and broad-sense heritability. The research was designed on a randomized completely block design (RCBD) with ten new F9 rice lines and two comparison varieties as treatments, repeated three times. The variables observed were plant height, maximum number of tillers, number of productive tillers, flowering time, harvesting time, panicle length, number of grain per panicle, number of filled grains per panicle, number of empty grain per panicle, grain length, grain width, grain thickness, and grain yield per hectare. The data were analyzed using Analysis of Variance (ANOVA), if there was a difference between the mean values, it was continued with a 5% LSD test. The results showed that (i) the genotypes tested showed wide genetic and phenotypic diversity, (ii) based on the analysis of GDC, PDC, and broad sense heritability, the appearance of phenotypes of several agronomic characters was controlled by genetic factors.

Genetic Variance and Correlation of Forage Yield and Quality Traits in Tropically Adapted Maize

Two F2 populations segregating for biomass yield and forage quality traits were developed from two separate crosses of tropically adapted maize inbred lines. The parental, F1 and F2 generations of both crosses were evaluated to estimate broad sense heritability, genetic advance and correlations for these traits to suggest the best traits as selection criteria towards breeding forage maize with high yield and quality.In Cross 1, biomass yield trait with the highest broad-sense heritability was plant height (70.03%), whereas forage quality trait with the highest heritability estimate was crude protein content (66.60%). Heritability estimates in Cross 2 were high for all biomass yield traits and forage quality traits (>50% for all traits). Indigestible cell wall component represented by acid detergent lignin content was found to be highly heritable in both populations. High genetic advance as percent of mean were found for fresh and dry plant yield as well as for lignin content in both populations. Correlation analysis on all traits showed that all biomass yield components were significantly correlated. All traits related to cell wall content were positively correlated and acid detergent lignin was positively correlated with dry plant yield. Traits with high to moderate heritability and high predicted genetic advance, namely plant height, fresh plant yield and protein content can be used as selection criteria to improve maize biomass yield and nutritive quality for forage utilization. Selecting for higher biomass yield would also result in selecting individuals with higher lignin content as shown by the correlation analysis.

Accurate Determination of Genotypic Variance of Cell Wall Characteristics of a Populus trichocarpa Pedigree Using High-Throughput Pyrolysis-Molecular Beam Mass Spectrometry

Background Pyrolysis-molecular beam mass spectrometry (py-MBMS) analysis of a pedigree of Populus trichocarpa was performed to study the phenotypic plasticity and heritability of lignin content and lignin monomer composition. Instrumental and microspatial environmental variability were observed in the spectral features and corrected to reveal underlying genetic variance of biomass composition.Results Lignin-derived ions (including m/z 124, 154, 168, 194, 210 and others) were highly impacted by microspatial environmental variation which demonstrates phenotypic plasticity of lignin composition in Populus trichocarpa biomass. Broad-sense heritability of lignin composition after correcting for microspatial and instrumental variation was determined to be H2 = 0.56 based on py-MBMS based on ions known to derive from lignin. Heritability of lignin monomeric syringyl/guaiacyl ratio (S/G) was H2 = 0.81. Broad-sense heritability was also high (up to H2 = 0.79) for ions derived from other components of the biomass including phenolics (e.g., salicylates) and C5 sugars (e.g., xylose). Lignin and phenolic ion abundances were primarily driven by maternal effects, and paternal effects were either similar or stronger for the most heritable carbohydrate-derived ions.Conclusions We have shown that many biopolymer-derived ions from py-MBMS show substantial phenotypic plasticity in response to microenvironmental variation in plantations. Nevertheless, broad-sense heritability for biomass composition can be quite high after correcting for spatial environmental variation. This work outlines the importance in accounting for instrumental and microspatial environmental variation in biomass composition data for applications in heritability measurements and genomic selection for breeding poplar for renewable fuels and materials.

Genetic Analysis of Tertiary Rice Panicle Branches

Panicle branching trait of rice is one of the key factors in detemining grain yield. This study was aimed to elucidate the genetic inheritance pattern of the tertiary rice panicle branches trait. Six rice populations i.e F1, F1R, F2, F2R, BC1P1, and BC1P2 generation including parental lines were generated as materials. The experiment was conducted at IPB University, Bogor, Indonesia from April 2017 to February 2019. Several parameters of genetic inheritance was observed. The result revealed that the inheritance of the tertiary panicle branching was controlled by many genes with the high broad-sense heritability and the moderate narrow-sense ones. Based on the scaling test, it was observed that additive dominant model did not fit to the number of tertiary branches and the number of grains of tertiary panicle branches. These phenomenons suspected may due probably to the effect of epistasis. In the advanced analysis employed by using the joint scaling test revealed that the gene action of the number of tertiary branches and number of grains on the tertiary branches were additive and additive×additive.