Formação de mudas de Coffea arabica L. cv. rubi utilizando sementes ou frutos em diferentes estágios de desenvolvimento

Abstract

Coffee seeds present slow germination and poor storage potential, which makes it difficult seedling formation in a suitable time and under climatic conditions favorable to the crop establishment. The propagation of the coffee plant by means of seedlings coming from seeds is still widely accomplished and reduction of the time for the obtaining a good developed and vigorous seedlings is highly desirable, aiming at a good establishment of the stand and the reduction of the percentage of replanting. Considering that coffee seeds achieve their maximum germination at the green yellowish and red ripe stages, the present work was undertaken with the purpose of testing an alternative to obtain seedlings, by using both berries and seeds at several developmental stages. The experiment was conducted in the seedling nursery of the Coffee Culture Sector at the Federal University of Lavras. The design was in randomized blocks with four replicates and the seedlings were produced in bags with substrate of earth, manure, simple superphosphate and potassium chlorite (standard substrate). Nine sowing treatments were tested by utilizing seeds or berries Coffea arabica L. cv. Rubi: 1) berries at the green stage; 2) berries at the green stage 10 days after harvest; 3 ) berries at the green yellowish stage; 4) berries at the green yellowish stage 10 days after harvest; 5) berries at the red ripe stage; 6) seeds from red ripe berries dried to 15% of the water content; 7) seeds from red ripe berries dried to 15% and without parchment; 8) seeds from red ripe berries, dried to 15% of water parchment and with a parchment and pre-soaked in water for six days; and 9) seed from red ripe berry, dried to 15% without a parchment and pre-soaked in water for six days. One hundred and forty days after the start of the experiment, the percentage of emergence (E), emergency velocity index (EVI) and the percentage of seedlings with at least one pair of true leaves (TL) were evaluated. One hundred and eighty after the start of the experiment, the evaluation of the seedlings was proceeded by means of the measurements of stem diameter (D), seedling height (H), root system dry matter (RSDM), shoot dry matter (SDM), leaf area (LA) and of the number of pairs of leaves (NPL). The treatments of sowing of seeds without a parchment stood out in every evaluated seed characteristics and presented practically the same performance of the seedlings of seeds without a parchment and pre-soaked in water for six days. In the characteristics of seedling evaluation, the treatments of berries of green yellowish and of seeds without a parchment did not differ statistically from one another and were superior to the sowing of seeds with a parchment. The soaking of coffee seeds with a parchment in water brings no advantage to seedling formation.