No abstract

This work aimed to evaluate the interference of seed desiccation on the occurrence of root protrusion and the formation of normal cambuci seedlings. Seeds were obtained from mature fruits collected from adult plants and submitted to oven drying with forced air circulation at 30±2°C in order to obtain different water contents. The seeds were then submitted to the germination test in a completely randomized design at 25°C and 12 hours photoperiod, and were weekly evaluated for a period of 90 days, regarding the number of seeds with root protrusion, the number of dead seeds and normal seedlings. At the end the germination speed index (GSI) the mean germination time (MGT) and the average speed of germination (ASG) were calculated. Any of these variables were significantly affected until the water content decreased to 14.9%, whereas at 9.1% and 6.6% water contents, there was a significant reduction of root protrusion and GSI, and a higher percentage of dead seeds. Cambuci seeds tolerate desiccation down to 15% water content without losing viability.

The objective of this work was to evaluate the air-layering and grafting techniques in the production of cambuci (Campomanesia phaea) plants. Two experiments were conducted in randomized complete blocks for air-layering, using adult cambuci plants, and two completely randomized for the grafting, using seedlings. Air layering was evaluated with different rates of indolebutyric acid; the splice, side-veneer, and chip-budding techniques were used for grafting. Air-layering rooting was not favored by the application of indolebutyric acid rates, whereas side-veneer grafts ensured the fixation of 6% of the grafts. Histological analyses of the air layers revealed the action of parenchyma cells from the xylem in the formation of structures similar to calluses. In the grafted plants, these cells ensured tissue union and regeneration. The air-layering technique was unfeasible, but grafting is recommended to establish cambuci tree genotypes.

The objective of this work was to evaluate air layering, cutting, and grafting, with different indolebutyric acid (IBA) rates, for the vegetative propagation of Eugenia involucrata. Air layering was carried out for two consecutive years with five different IBA rates. Cutting was tested for woody and herbaceous cuttings, using four IBA rates, in three seasons. The grafting methods – cleft graft and splice graft – were tested in two seasons. For the air layering, cutting, and grafting trials the experimental designs were randomized complete blocks, completely randomized in a 3x4 factorial arrangement, and completely randomized, respectively. Plants were evaluated for rooting, survival percentage, and shoot development. In air layering, low rooting rates of 0 to 50% were observed, the use of IBA showed no consistent results, and no resulting propagules survived after being transplanted. The cutting technique showed low survival, rooting, and leaf retention rates, with no consistent effect of IBA rates. Grafting showed 35 to 50% graft fixation, with no significant difference between the splice and cleft grafting techniques. The air layering and cutting techniques are not efficient for the propagation of E. involucrata, as they do not favor the survival and rooting of seedlings. Grafting, by both techniques, is the most efficient method for E. involucrata propagation.