Reproductive analyses of intraspecific Paspalum notatum Flügge hybrids.

Abstract

Paspalum notatum is an important forage native to Southern Brazil and one of the most promising fodder species in terms of productivity, quality, resistance and growth speed. The objective of this study was to evaluate the reproductive mode and fertility of hybrid progenies resulting from artificial crosses among artificially duplicated sexual plants, selected intraspecific hybrids of the UFRGS breeding program and apomictic ecotypes of the species. The resulting F 1 progenies were represented by 24 plants with high pollen viability (varying from 82.15 to 99.67%) and 1.2:1 segregation for the sexual: apomictic reproduction mode, indicating predominantly sexual hybrids, due to distorted segregation. In the apomictic plants, most chromosomes paired as bivalents in diakinesis. Since the low presence of abnormalities observed in the meiotic chromosome pairing and the high pollen viability of the hybrids, all plants were confirmed as promising parents for future crosses.

Genomic affinity in hybrids of B-genome Arachis species: new genetic resources toward peanut improvement

“…Although several crosses between B genome species have been conducted, there is only one report of A. ipaënsis × A. williamsii (Simpson and Faries 2001), and no meiotic studies have been performed to analyze their genomic homology. Meiotic studies provide relevant information on the fertility of hybrids, and therefore can accelerate the success of breeding programs (Krycki et al 2020). Furthermore, the ability of hybrids to produce viable unreduced gametes, such as those reported in [A. duranensis × A. ipaënsis] 2x hybrids (García et al 2020), may increase with interspecific crosses and environmental factors (Kreiner et al 2017).…”