Genetic variability of the components of seed yield in interspecific hybrids of Paspalum

Abstract

-This study aimed to determine the variability and expression of the components of seed yield in twenty-three apomictic Paspalum plicatulum × Paspalum lepton hybrids and two male parent plants (P. lepton). We used a randomized block design with genotypes individually arranged into ten blocks. The variables were: number of total tillers/plant, number of vegetative tillers/plant, number of reproductive tillers/plant, percentage of reproductive tillers, number of racemes/inflorescence, number of seeds/inflorescence, weight of a thousand seeds, and seed yield. We assessed genetic variability using multivariate procedures: generalized Mahalanobis distance, Tocher's clustering optimization method, and quantification of the relative contribution of the variables. The quantification of variability, based on the components of seed yield of Paspalum plicatulum × Paspalum lepton hybrids, allows the formation of six groups of genotypes using Tocher's method, with high means for the characteristics studied. Weight of a thousand seeds and number of seeds/inflorescence were the traits that most contributed to the genetic dissimilarity. Genetic crosses involving genotype 10E5052 from group VI and 10E4071 from group V could be undertaken to isolate high yielding segregants, since these genotypes have high seed yielding potential.Key Words: apomitic genotypes, Plicatula, seed production, weight of thousand seeds Revista Brasileira de Zootecnia

Transference of natural diversity from the apomictic germplasm of Paspalum notatum to a sexual synthetic population

“…There were no significant differences either for seed quality traits or for pollination methods among the three groups of genotypes. The average seed weight reported for the three analysed groups in this work (3.58 g) was greater than that reported by Lopes et al () for apomictic tetraploid entries (2.27 g). In turn, the average seed weight in the three groups of genotypes was similar to those reported by Rios et al () for the apomictic tetraploid cultivar Argentine (≈3.6 g).…”

Genetic parameters and predicted gains with selection of interspecific hybrids of Paspalum for seed production

“…We highlight the high phenotypic variation of the WTS and NSI traits, basically composed by the variation of the genotype (Table 1). According to Lopes et al (2017), WTS and NSI were the most efficient (largest relative contribution) in explaining genetic variability among P. plicatulum × P. lepton hybrids, showing the importance of these variables as a component in the production of seeds and, possibly in the selection of superior genotypes.…”

“…Genetic gains ranged from 0.5 to 1.3 racemes per inflorescence (21.9%) for this trait. According to Lopes et al (2017), the expression of the variability of the NRI trait was equal in two years of evaluations, emphasizing the same genotype of this study (10E4026). It is worth noting that the P. plicatulum species (female genitor) presents 3-7 racemes per inflorescence and the P. lepton species (male genitor) presents 2-5 racemes per inflorescence (Wunderlin et al 2017), probably contributing to the variability of this trait after hybridization.…”

“…According to the literature, the main components of the production of Paspalum seeds are the TT, RT, NSI and WTS traits (Lopes and Franke 2011, Lopes et al 2016, Lopes et al 2017. The use of these traits favors the choice of superior performance genotypes, through indirect selection in traits of difficult selection and measurement, such as seed production.…”

Managing forage and turf‐type bahiagrass for seed production

“…Similar results were reported for Paspalum atratum Swallen (Phaikaew, Pholsen, & Tudsri, 2001), interspecific hybrids of Paspalum spp. (Ramos Lopes et al, 2017), and Brachiaria spp. (Hare, Pizarro, Phengphet, Songsiri, & Sutin, 2015).…”