Agronomic, nutritive value, reproductive, cytogenetic, and molecular aspects of Paspalum accessions: Contribution to the development of new forage cultivars

Abstract

This study investigated the agronomic, nutritive value, cytogenetic, molecular, and reproductive aspects of twenty‐five Paspalum accessions to support breeding programs. The agronomic aspects and the nutritive value were evaluated in a randomized block experimental design with four replications, and with monthly repeated measures for 2 years. For the molecular characterization 16 microsatellite markers developed for different Paspalum species in previous works were used. The number of chromosomes was determined by visualizing the meiotic cells and the DNA content was determined by flow cytometry. The embryo sac clarification technique was used to characterize the reproductive system. The results indicated genetic variability for all the variables related to yield and nutritive value. For almost all variables, the values of Paspalum accessions were higher than those of the commercial cultivars Megathyrsus maximus cv. Tanzania and Urochloa brizantha cv. Marandu, used as references. However, the accessions showed in vitro dry matter digestibility values lower than the mean value presented by the references. The groups formed in the molecular analysis showed correspondence to the groups observed in the principal components analysis, considering the variables related to yield and nutritive value. Most accessions were revealed to be tetraploid with 40 chromosomes and most accessions belonging to the Virgata group displayed a sexual embryo sac structure. Some crosses can be indicated for genetic breeding, due to a superior genomic affinity between the accessions and the higher probability of heterosis in the progeny. These results provide subsidies to genetic plant breeding programs that use these accessions.

Characterization of Paspalum genotypes for turfgrass cultivars development

“…It comprises about 330 species (Zuloaga & Morrone, 2005), 216 of which are found in Brazil (Valls et al., 2023). A genebank of Paspalum with 538 accessions, collected in different regions of Brazil and representing 60 species, is hosted at Embrapa Southeastern Livestock, located in São Carlos, SP, Brazil (Matta et al., 2023). The remarkable range in plant size, leaf length, and growth habit observed within the Embrapa's Paspalum genebank indicates potential for diverse applications, from forage production to both ornamental and functional lawn uses.…”

Lignin, glutathione and kinases play important roles inPaspalum regnelliidefense against spittlebug (Mahanarva spectabilis) attack

“…An alternative is to use a native genus that is more resistant than other forages to spittlebugs, such as Paspalum (Gusmão et al, 2016), which originated from the tropical and subtropical regions of the Americas and is composed of species with high potential for pasture (Acuña et al, 2019; Novo et al, 2016). Embrapa Pecuária Sudeste maintains a Paspalum germplasm bank that allows breeding program development using Paspalum regnellii as a source of sexuality in crosses (Matta et al, 2023). Moreover, it is a perennial species with good biomass production, some resistance to shading and high forage potential (Bortolin et al, 2019).…”