Brachiaria decumbens intraspecific hybrids: characterization and selection for seed production

Abstract

Brachiaria decumbens has great importance in the national beef cattle scenario due to its high forage yield potential and high adaptability to acid soils and low fertility. In order to obtain new cultivars, intraspecific hybrids, previously selected by the Brachiaria breeding program, were evaluated in 2013 and 2014 for phenological characteristics and seed production potential through their production components, aiming to obtain cultivars with satisfactory production agronomic characteristics and forage yield, resistant to 'cigarrinhas-das-pastagens' (Tomaspia sp.) and good seed production. Estimates of phenotypic correlation and analysis of variance were performed using the SAS 9.3 software. From the results obtained in both consecutive years, it was observed that there was a correlation between the reproductive tiller number (RT) and the pure seeds (PS) weight in the seedbeds of the second year of production around 70% (p < 0.01), which can be considered as a parameter to estimate the production of pure seeds before the start of flowering.Híbridos intraespecíficos de Brachiaria decumbens: caracterização e seleção para produção de sementes RESUMO -Brachiaria decumbens tem grande importância no cenário nacional da pecuária de corte por apresentar alto potencial produtivo forrageiro e alta adaptabilidade a solos ácidos e de baixa fertilidade. Com o intuito de ser obter novas cultivares, híbridos intraespecíficos, previamente selecionados pelo programa de melhoramento de Brachiaria, foram avaliados nos anos de 2013 e 2014, quanto a caracteres fenológicos e potencial de produção de sementes por meio de seus componentes de produção, visando a obtenção de cultivares com características agronômicas satisfatórias de produção e de produtividade de forragem, com resistência às cigarrinhas-das-pastagens e boas produtoras de sementes. As estimativas de correlação fenotípica e análise de variância foram realizadas pelo software SAS 9.3. A partir dos resultados obtidos nos dois anos consecutivos, observou-se que, houve correlação entre número de perfilhos reprodutivos (PR) e peso de sementes puras (SP) nos canteiros do segundo ano de produção em nível de 70% (p<0,01), o que pode ser considerado como parâmetro para se estimar a produção de sementes puras antes do início do florescimento.Termos para indexação: fenologia, apomixia, genótipos, melhoramento de forrageiras.

Comparison of selection methods among and within full‐sibling progenies in Urochloa humidicola

“…Potentially superior apomictic hybrids can be directed by the breeder for clonal testing, as apomixis allows to fix additive and non‐additive genetic effects while fully preserving the heterosis manifested in the hybrid combination. Superior sexual hybrids are new sources of sexuality with the possibility of their use as parents in future crosses (do Valle, Jank, & Resende, ; Monteiro et al, ).…”

biochemical attributes and establishment of tree seedlings in soil after urochloa decumbens cultivation in soil with deposition of iron mining residues

“…U. decumbens is known for being a very aggressive plant in terms of competition with other species, and the ability to grow in soils with low fertility and physical limitations (Flávio Neto et al, 2015;Monteiro et al, 2016;Silva et al, 2019). These characteristics explain the absence of significant differences in the plant's SDW in soil affected with mud and tailings from iron ore mining, compared with non-impacted treatment (Tab.…”

Effect of aqueous extracts of Brachiaria decumbens on the development of ornamental pepper

“…Brachiaria decumbens is of great importance in the Brazilian cattle industry, due to its high potential for forage production and adaptability to acid soils with low fertility (Monteiro et al, 2016). It is believed that substances produced through the metabolism of B. decumbens plants and released by dissolution in water may influence the development of pepper plants, due to the presence of mineral nutrients, amino acids and organic acids, carbohydrates or growth regulators.…”