Guava breeding via full-sib family selection: conducting selection cycle and divergence between parents and families

Abstract

The major hindrance to guava fruit (Psidium guajava L.) growing is the low availability of cultivars for use by Brazilian producers, who usually rely on few options of genotypes to implement the crop. In the present study, 11 full-sib families were evaluated in a randomized-block experimental design with three replicates, in order to more efficiently select superior genotypes. Genetic parameters were estimated and the best genotypes were selected based on genetic value by applying the REML/BLUP statistical procedure. Additionally, genetic divergence was estimated based on the mean Euclidian distance between the individuals selected via BLUP. Based on genetic divergence, the best genotypes were selected for use as parents in new crosses aiming at continuity of the guava breeding program. The mean values of the traits of selected individuals surpassed the mean values of their parents, confirming that the strategy of obtaining full-sib families is effective in generating considerable gains.

Selection between and within half-sibling progenies of Ilex paraguariensis for adventitious rooting of mini-cuttings

“…The REML/BLUP analysis procedure enabled the estimation of the genetic parameters by their genotypic values and predicted gains, being effective in identifying superior genotypes, as found by Bezerra et al (2020). The estimates of individual heritability coefficients in the strict sense (h 2 ) were higher than those obtained in individuals within the progeny (h 2 ad), for all evaluated traits (Table 2).…”

“…These results indicated a high magnitude of genetic variation available for selection (Pimentel et al 2014), enabling significant genetic gains from selection between and within mate progenies based on adventitious rooting competence. According to Bezerra et al (2020) this shows the existence of variability that can be exploited by selection and, consequently, the possibility of identifying superior genotypes for these traits. The CV gi values between 25.9% and 41.6% were observed for rooting traits of P. persica cuttings (Oliveira et al 2018).…”

Theobroma Grandiflorum Breeding Optimization Based on Repeatability, Stability and Adaptability Information

“…Therefore, smaller-scale heritabilities, as observed at the individual level, can jeopardize the genetic gains. A previous study (Bezerra et al 2020) considered this fact to recommend the selection of full-sib families in guava (Psidium guajava L.) to achieve greater genetic gains. Another attribute of heritability is related to selection accuracy.…”

Theobroma grandiflorum breeding optimization based on repeatability, stability and adaptability information

“…The identification of these genotypes is essential for advancing the improvement of the species [21]. In this context, progenies 36,37,11,5,49,23,6, and 25 are the most suitable, as they stand out for both traits simultaneously.…”

“…Therefore, smaller-scale heritabilities, as observed at the individual level, can jeopardize the genetic gains. A previous study [36] considered this fact to recommend the selection of full-sib families in guava (Psidium guajava L.) to achieve greater genetic gains. Another attribute of heritability is related to selection accuracy.…”