Urochloa spp. multivariate performance: Similarities and divergences among intra‐ and interspecific populations

Abstract

Multivariate analysis is a tool that breeders can use to compare populations and select genotypes for specific purposes. This study used principal component analysis to compare three intraspecific and three interspecific populations of Urochloa spp. based on insect resistance, agronomic, and seed production characteristics. This multivariate strategy exposed completely different profiles and important differences among these populations despite their close genomic ancestry. In general, interspecific populations had greater variability than intraspecific populations for agronomic traits, seed production, and spittlebug resistance. Consequently, crosses among different species, whenever possible, are a better option to obtain new Urochloa breeding populations. However, the breeding of intraspecific populations is also an excellent option to improve specific traits related to each species, which can then be used to speed the breeding in the interspecific programs. Multivariate analysis demonstrated substantial variability within progenies of the interspecific Urochloa populations that can be used to improve insect resistance and productivity of tropical pastures.

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

“…However, complex genetic architectures are obtained by combining these traits because of the correlation from close linkages between genes or when they are responsible for multiple characteristics. Therefore, the main focus of forage breeding is still biomass production, which is the trait that is present in practically all cultivar studies (Casler & Santen, 2010), and for that reason, the largest pasture area in South America is composed of Urochloa species with African origin, primarily U. decumbens and U. brizantha (Matias et al ., 2021). Despite their productivity qualities, these forage grasses do not survive well under biotic stress and are more susceptible to many spittlebug species than other grass species, such as those from the genus Paspalum (Gusmão et al ., 2016).…”

“…Currently, the predominant pasture area in South America is composed of African species with high productivity levels, such as Panicum and Urochloa (Matias et al, 2021). This prevalence can be attributed to breeding efforts focused on enhancing field performance (Casler and Santen, 2010).…”

Herbage and animal responses on continuously stocked ‘Ipyporã’ and ‘Mulato II’ brachiariagrasses

“…Forage species and/or genotype diversification is essential to reduce environmental and economic risks (Holmann & Peck, 2002). Within the Amazon Biome, a high proportion of planted grassland is Marandu palisadegrass, susceptible to insects (Matias et al, 2021) and has been suffering from death syndrome (Tesk et al, 2020). Evaluation of alternatives to Marandu is important to increase plant diversity of forage‐livestock systems and minimize risk.…”