Coffee Science

URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3355

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    Alternative treatments diminish oviposition and viability of Leucoptera coffeella (Lepidoptera: Lyonetiidae) eggs and larvae on coffee plants
    (Editora UFLA, 2021) Androcioli, Humberto Godoy; Hoshino, Adriano Thibes; Meneghin, Ana Maria; Ventura, Mauricio Ursi; Guide, Bruna Aparecida; Hata, Fernando Teruhiko; Menezes Junior, Ayres de Oliveira
    The effects of alternative treatments on the oviposition and viability of Leucoptera coffeella eggs and larvae were evaluated. Under controlled conditions, coffee sprouts cv. IAPAR-59, eight months old, were sprayed with brown propolis extract (1%), pyroligneous extract with pepper and garlic (PEPG) (2%), silicate clay (2%), kaolin (5%), lime sulfur (2%), neem oil (1%) and kaolin + neem oil (5% + 1%), distilled water and no treatment. In a first no-choice bioassay, coffee sprouts were sprayed before oviposition and kept in cages, where adult insects within three days after emergence were released. Adults remained in the cages for 24 hours. Eggs were then counted. 10 eggs per sprout were preserved to verify larval mortality. The number of eggs when treated with propolis extract, neem oil, kaolin + neem oil and PEPG decreased in the evaluations. Treatments with neem oil caused greater larval hindrance. Eggs laid on leaves were also sprayed with the treatments. Egg viability was reduced by treatments containing neem oil and lime sulfur. Neem oil treatments resulted in slim adult emergence; intermediate viability with lime sulfur and slight hindrance with silicate clay. Finally, treatments were also sprayed on leaves, hosting first or third instar larvae. Neem treatment caused high mortality for 1st and 3rd instar larvae, however, this effect was reduced when mixed with kaolin. Nonetheless, these negative effects disappeared when considering the adult survival ratio. Results indicated that propolis extract, PEPG and neem oil treatments are suitable for reducing egg deposition, neem oil considerably diminished larvae survival and adult emergence.
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    Decomposition and nutrients released from forest and perennial crops associated with organic coffee
    (Editora UFLA, 2021) Araujo, João Batista Silva; Silva, Matheus Wandermurem da; Lima, Wallace Luís de; Pereira, Ana Claudia Hertel; Endringer, Denise Coutinho; Souza, Jacimar Luís de
    Agroforestry consortia increase organic matter and nutrient cycling in agricultural systems. For this reason, the objective of this work was to study the release rate of nutrients and the decomposition of different organic residues, two times of the year, obtained from four cultures intercropped with conilon coffee, aiming to relate the released nutrients to the coffee needs. The decomposition of organic matter residues and the release of nutrients from Inga edulis, Musa spp, Gliricidia sepium, and Bactris gasipaes were evaluated in two different periods. I. edulis residues with a higher amount of polyphenols, and those of Musa spp, with a higher C/N ratio, showed slow decomposition. The decomposition rates were lower in experiments started in March and higher in August. Inga and banana have high residual values of nutrients at 270 days in the decomposition started in March.