Alternative substrates for the production of clonal Coffea canephora seedlings

O objetivo deste trabalho foi avaliar as propriedades físico-químicas da palha de café, do capim-elefante e da cana-de-açúcar isolados ou combinados entre si ou com compostos comerciais, bem como seu uso como substrato para a produção de mudas clonais de Coffea canephora. O experimento foi conduzido em duas etapas: uma para a caracterização físico-química dos substratos, e a outra para a avaliação do crescimento das mudas de café nesses substratos. Na primeira etapa, os tratamentos consistiram de palha de café (PC), capim-elefante (CE), cana-de-açúcar (CA), substrato comercial (SC), vermiculita (VM) e suas combinações. Na segunda etapa, avaliou-se, também, o substrato padrão (solo). A PC apresentou altas condutividade elétrica e densidade e baixos espaço de aeração e água disponível. A CA se destacou por seus menores pH e densidade e sua maior porosidade. A CA e o CE foram viáveis para a produção de mudas de café, sem diferir dos substratos comercial e padrão. Com exceção de PC+CE, PC+SC e CE+CA, os substratos combinados proporcionaram maior crescimento das mudas que os isolados. A PC foi viável como substrato apenas em combinação, principalmente com VM. A combinação de PC, CA e CE com o substrato padrão melhora a qualidade de mudas clonais de C. canephora.The objective of this work was to evaluate the physicochemical properties of coffee husk, elephant grass, and sugarcane alone or combined with each other or with commercial compounds, as well as their use as substrate for the production of clonal Coffea canephora seedlings. The experiment was carried out in two stages: one for the physicochemical characterization of the substrates, and the other for evaluations of the growth of coffee seedlings in these substrates. In the first stage, the treatments consisted of coffee husk (CH), elephant grass (EG), sugarcane (SC), commercial substrate (CS), vermiculite (VM), and their combinations. In the second stage, the standard substrate (soil) was also evaluated. CH presented a high electrical conductivity and density and a low aeration space and available water. SC stood out for its lower pH and density and its greater porosity. SC and EG were viable for coffee seedling production, not differing from the commercial and standard substrates. With the exception of CH+EG, CH+CS, and EG+SC, the combined substrates allowed of a greater seedling growth than the isolated ones. CH was only viable as a substrate when combined, especially with VM. Combining CH, SC, and EG to the standard substrate improves the quality of clonal C. canephora seedlings

Different volumes of tubes for clonal propagation of Coffea canephora from seedlings

The aim in the present study was to evaluate the growth of Coffea canephora cv. ‘Conilon BRS Ouro Preto’ seedlings in different tube volumes. The experiment was performed at Embrapa Rondônia plant nursery in Ouro Preto do Oeste, Rondônia, Brazil, from July to November 2013. The treatments consisted of five tube volumes (50, 100, 170, 280 and 400 cm3) plus one control composed by polyethylene bags (11 cm width x 20 cm height) with capacity of 770 cm3. The experimental design was a randomized complete block design with 15 replicates, formed by 15 clones that compose the Conilon ‘BRS Ouro Preto’ cultivar. The tube volume of 280 cm3 provide the best vegetative performance of seedlings, similarly to volume of 400 cm3, thus, the use of larger tubes would not justify. Tubes of 50, 100 and 170 cm3 produce seedlings with physiological quality similar to the control until 130 days after staking, but may limit the development of seedlings in a longer period