Hybrids of <i>Paspalum plicatulum</i> × <i>P. guenoarum</i>: Selection for forage yield and cold tolerance in a subtropical environment

Abstract

Selection of improved genotypes is important for pasture-based feeding systems in subtropical regions. Our goal was to identify hybrids of Paspalum with enhanced forage yield and cold tolerance across 2 sites [Bagé and Eldorado do Sul (ES)], in Rio Grande do Sul, Brazil. We evaluated 19 P. plicatulum × P. guenoarum hybrids, P. plicatulum genotype 4PT, P. guenoarum cultivars Azulão and Baio and, as Control, Megathyrsus maximus cv. Aruana. At both sites, the experimental design was a completely randomized block with 4 replications. Total dry mass (total-DM), leaf-DM and cold tolerance (ColdT) were recorded. At Bagé, hybrid 102069 produced higher total-DM and leaf-DM than the progenitors and cv. Aruana, while at ES, hybrids 102069 and 10308 produced higher total-DM than 4PT, Azulão and Aruana; hybrid 102069 had higher leaf-DM. At Bagé, 16 hybrids displayed ColdT similar to their progenitors and higher than Aruana, while at ES, 12 hybrids showed ColdT similar to Azulão and Baio and higher than 4PT and Aruana. This study demonstrated that hybrids of Paspalum with superior forage yield to their progenitors and Aruana, and hybrids with higher ColdT than 4PT and Aruana are in existence. The hybridization technique shows potential for producing alternative genotypes with higher forage yield and ColdT for sowing in subtropical regions.

IAPT chromosome data 36

“…Although less intensively studied than Paspalum notatum and subject to varying interpretations of its morphological circumscription, which may cast doubt on associated records of chromosome counts, P. plicatulum shows a similar situation, with full predominance of tetraploids, such as the one documented here from Paraná State in Brazil, and a few diploid counts reported from Argentina, Brazil and Mexico . A single colchicine-induced tetraploidization event of the diploid Argentine accession originally reported as Honfi 14 Sartor & al., 2009;Weihmüller & al., 2014) triggered a promising forage breeding program involving the induced tetraploid as a female parent in crosses with several apomictic tetraploid species of the informal group Plicatula (Aguilera & al., 2015;Novo & al., 2016Novo & al., , 2019Saraiva & al., 2021), emphasizing the good prospects for the continuous search for new sexual diploids.…”

Seed yield and quality of Paspalum notatum Flügge intraspecific hybrids

“…In segregating progenies for the mode of reproduction, sexual reproduction hybrids are necessary for obtaining genetic variability (Saraiva et al, 2021) in new cycles of crosses, while facultative apomicts produce seeds through both sexual and apomictic means. The sexual reproduction percentage varies by environmental conditions (Kandemir & Saygili, 2015).…”

Response of Bahiagrass hybrids to nitrogen fertilization or mixture with legumes

“…Pensacola in both evaluated traits. According to Saraiva et al (2021), the cold tolerance trait is essential in subtropical regions, because more tolerant genotypes may have greater persistence and a greater supply of forage for animals grazing during the winter, along with faster regrowth in the spring.…”