Determining the inheritance of agronomic traits in chili pepper

Abstract

The Capsicum genus is widely studied in many countries but most of research focuses on C. annuum. Although its importance as potential genetic resource for breeding to disease resistance and fruit quality, studies on genetics and breeding in C. baccatum var. pendulum are still scarce and it still remains as an underexploited crop. This paper aimed to study the inheritance of agronomic characteristics, to estimate the genetic parameters for seven agronomic traits in C. baccatum var. pendulum, using generation mean analysis and to verify the existence of major genes and polygenes with additive and non-additive effects, using the method of maximum likelihood with the aid of Monogen software. The agronomic traits evaluated were: number of fruits per plant (NFP); average fruit mass per plant (AFM); fruit length (FRL); fruit diameter (FRD); fruit pulp thickness (FPT); soluble solids content (SSC) and fruit dry mass (FDM). There was a significant difference among generations (P1, P2, F1, F2, BC1 and BC2) for all traits evaluated. Narrow sense heritability estimates ranged from 45% for NFP to 75% for FRD. By estimating the average degree of dominance (ADD), we found that partial dominance is the gene action involved in the genetic control for FRL and FRD, while additive effect was observed for NFP, FPT and SSC, complete dominance for FDM and overdominance for AFM. The additive-dominant model was sufficient to explain the results obtained for all evaluated traits. Maximum likelihood method identified the existence of polygenes with additive and dominance effects in SSC, FPT and FDM. Major gene effect was identified for FRL and NFP characteristics. The results indicated the complexity of the inheritance of these traits with the presence of major gene involved.

Heritability of morpho-agronomic traits in ornamental pepper

“…For FYP, Rêgo et al (2011) and Thakur et al (2019), evaluating C. baccatum and C. annuum respectively, reported high broad-sense heritability values, revealing little influence of the environment and highly contrasting parents. Conflicting results for FYP by Bento et al (2016) with C. baccatum, who showed low values for broad-and narrow-sense heritability for this trait.…”

“…Significant values for all traits were found for m and d in the additive-dominant model, except for F R D. The dominant effects (h) were significant for all traits (Table 3). Santos et al (2014), in studies with C. annuum, and Bento et al (2016), with C. baccatum, reported the adequacy of the additive-dominant model controlling the CW and F R D traits, respectively. According to Cruz and Regazzi (2001), high R 2 estimates express the degree of similarity between the estimated and observed values, indicating the accuracy of the model adopted.…”

“…Regarding PT and DMC, Bento et al (2016), in studies with Capsicum baccatum cv. Pendulum, observed low broad-and narrow-sense heritability values, corroborating those reported in the present study.…”

“…The additive-dominance model explained only three variables: CW (81.7%), F R D (71.1%) and SYF (84.1%) (Table 3). Santos et al (2014) and Bento et al (2016) reported the adequacy of the additive-dominant model controlling the CW and F R D traits, respectively. Significant values for all traits were found for m and d in the additive-dominant model, except for F R D. The dominant effects (h) were significant for all traits (Table 3).…”

Research Article Multiple genetic resistances in Capsicum spp.

“…These genotypes include all species studied here, except for C. frutescens, likewise the results observed for AUDPC ( Table 2). The experimental hybrids H6 and H7 were resistant to BS and, despite not having any relationship (same parent), they have agronomic characteristics required by consumer market (Gonçalves et al, 2011;Bento et al, 2016) and were deemed promising to be released to farmers after cropping values tests. Genotype UENF 1750 (C. annuum var.…”