Adriene Woods Pedrosa

Concentração foliar de nutrientes em cultivares de Coffea arabica L. sob espaçamentos adensados

Os plantios adensados de cafe proporcionam melhor reciclagem de nutrientes e consequentemente reduzem a perda de nutrientes do solo por erosao, lixiviacao e oxidacao da materia orgânica. Avaliaram-se as influencias de diferentes espacamentos na concentracao de macro e micronutrientes em folhas de cafeeiro das cultivares IAC 44, IAC 99, MG 1192, Katipo, MG 6851 e UFV 3880. Ao inicio do experimento o solo foi arado para incorporacao do calcario. As mudas foram plantadas em covas de 0,30 x 0,30 x 0,40 m, espacadas entre si em 0,75 m na fileira. Na adubacao de plantio aplicou-se 200 g de Fosfato Natural de Araxa, 50 g de Superfosfato Simples por cova, e 15 dias apos o plantio 2L/cova de esterco em cobertura. As demais adubacoes foram realizadas segundo o recomendado para a cultura do cafe. O delineamento foi em blocos casualizados num esquema fatorial 6 x 4 (seis cultivares x quatro espacamentos), com seis repeticoes. As parcelas foram compostas por quatro fileiras de 4,50 m de comprimento, espacadas entre fileiras em 1,0; 1,5; 2,0 e 2,5 m. Amostras de folhas foram retiradas aos 21 e 34 meses para avaliacao dos teores foliares de macro e micronutrientes. O adensamento nao influenciou na concentracao de nutrientes nas folhas aos 21 meses apos o plantio, mas influenciou as concentracoes foliares de P, K e Mg aos 34 meses apos o plantio.

Boron, Copper, and Zinc Affect the Productivity, Cup Quality, and Chemical Compounds in Coffee Beans

Micronutrients perform specific and essential functions in plant metabolism, and their deficiency may lead to metabolic disturbances that affect coffee production and quality beverage. In Brazil, the B, Cu, and Zn are the main micronutrients, and these are provided by soil or foliar fertilization, frequently with low recovery efficiency. This work objected verifying the feasibility of supplying of B, Cu, and Zn via insertion of tablets in the orthotropic branch of Coffea arabica, as well as to evaluate the coffee plant response in terms of productivity and quality of the beverage. Adult plants received B, Cu, and Zn, each micronutrient alone or combined with the other two, by foliar fertilization or by tablets inserted in the trunk base. The productivity, cupping quality, and some chemical indicators of beans quality were evaluated in two crop seasons. Boron, copper, and zinc supplied by foliar spray or solid injections in the trunk influenced the chemical composition and quality of the coffee beans, characterized by the cupping test and the levels of caffeine, trigonelline, sucrose, glucose, arabinose, mannose, 3-caffeoylquinic acid, 5-caffeoylquinic acid, polyphenol oxidase activity, and total phenolic compounds. Copper and zinc were equivalent in either form of supply regarding the production and quality of coffee.