Bragantia

URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/9887

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    Arbuscular mycorrhizal fungi inoculation for coffee seedling production with commercial and conventional substrates
    (Instituto Agronômico (IAC), 2023-05-22) Silveira, Adriana Parada Dias; Tristão, Fabrício Sales Massafera; Fernandes, Ana Olívia; Andrade, Sara Adrian Lopez; Cipriano, Mateus Aparecido Pereira
    Coffee seedlings are commonly produced on substrate composed of a mixture of soil and cattle manure, supplemented with chemical fertilizers. Alternatives to reduce production costs and produce seedlings of greater quality and health include the use of commercial organic substrates, which require less handling. The use of beneficial microorganisms such as arbuscular mycorrhizal fungi (AMF) can be considered a good alternative for production of more vigorous coffee seedlings. The main goal of this study was to evaluate the effect of the inoculation of AMF isolates on coffee seedlings development in a commercial organic substrate (based on coconut fiber) and conventional substrate (mixture composed of soil and cattle manure compost). Ten AMF were tested: Rhizophagus irregularis, Glomus macrocarpum, Claroideoglomus etunicatum, Rhizophagus clarus, Glomus spp., Gigaspora margarita, Acaulospora morrowiae, Acaulospora scrobiculata, Acaulospora spp., and Dentiscutata heterogamma. Plant growth, shoot P content, mycorrhizal colonization, extraradical mycelium length, phosphatase activity, and photosynthetic pigments were evaluated. The effects of mycorrhization depended on both the inoculated fungal species and the substrate for seedling cultivation. Inoculation of G. margarita, Acaulospora spp., and Glomus spp. in the conventional substrate conferred the best growth plant responses, increasing shoot biomass by 160 to 320%. In the commercial substrate, the most efficient AMF were R. clarus, Glomus spp, A. morrowiae and A. scrobiculata, with up to 149% of shoot biomass increase. The commercial organic substrate and the inoculation of some of the AMF isolates were highly beneficial to coffee seedlings development and can replace the use of the conventional substrate. These results open new opportunities for the use of AMF as an inoculant to improve coffee seedling production in commercial organic substrates.
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    Multiple-trait model by Bayesian inference applied to environment efficient Coffea arabica with low-nitrogen nutrient
    (Instituto Agronômico (IAC), 2023-04-14) Silva Júnior, Antônio Carlos da; Moura, Waldênia de Melo; Torres, Lívia Gomes; Santos, Iara Gonçalves dos; Silva, Michele Jorge da; Azevedo, Camila Ferreira; Cruz, Cosme Damião
    Identifying Coffea arabica cultivars that are more efficient in the use of nitrogen is an important strategy and a necessity in the context of environmental and economic impacts attributed to excessive nitrogen fertilization. Although Coffea arabica breeding data have a multi-trait structure, they are often analyzed under a single trait structure. Thus, the objectives of this study were to use a Bayesian multitrait model, to estimate heritability in the broad sense, and to select arabica coffee cultivars with better genetic potential (desirable agronomic traits) in nitrogen-restricted cultivation. The experiment was carried out in a greenhouse with 20 arabica coffee cultivars grown in a nutrient solution with low-nitrogen content (1.5 mM). The experimental design used was in randomized blocks with three replications. Six agromorphological traits of the arabica coffee breeding program and five nutritional efficiency indices were used. The Markov Chain Monte Carlo algorithm was used to estimate genetic parameters and genetic values. The agromorphological traits were considered highly heritable, with a credibility interval (95% probability): H2 = 0.9538 – 5.89E-01. The Bayesian multitrait model presents an adequate strategy for the genetic improvement of arabica coffee grown in low-nitrogen concentrations. Coffee arabica cultivars Icatu Precoce 3282, Icatu Vermelho IAC 4045, Acaiá Cerrado MG 1474, Tupi IAC 1669-33, Catucaí 785/15, Caturra Vermelho and Obatã IAC 1669/20 demonstrated greater potential for cultivation in low-nitrogen concentration.