Minijardim clonal de oliveira: produtividade e enraizamento de miniestacas

Abstract

The olive tree Olea europaea L. is a crop of current and promising importance for several producing countries including, Brazil, although its propagation by seed and vegetation encounters difficulties, especially the adventitious rooting of cuttings and minicuttings. The aim of this study was to evaluate the influence of season, calcium concentration in the nutrient solution and IBA on the performance and productivity of the clonal minigarden and rooting of minicuttings of olive (Olea europaea L.), cultivars 'Arbosana', 'Koroneiki' and 'Grappolo 541'. The experiment was carried out in a randomized block design in a factorial arrangement (3x4x6x2) with split plots over time, with the factors consisting of cultivars ('Koroneiki', 'Arbosana' and 'Grappolo 541'), seasons (summer, spring, autumn, winter), six concentration of Ca (1, 2, 4, 6, 8 and 10 ml L -1 ) and the IBA (absence and 3000 mg L -1 ). The survival of ministumps (%), number of shoots, length of shoots, number of nodes per shoot, number of leaves per shoot and number of minicuttings per ministump per square meter per year were measured. In minicutting, was evaluated survival, rooting, callogenesis (%), number of roots, length of the longest root (cm), the total length of roots (cm), root dry matter (g), stem dry matter (g) and total dry matter (g). As for anatomical parameters in the roots, the total area of ​​the root (µm 2 ), area of ​​the vascular cylinder (µm 2 ), area of ​​the cortex (µm 2 ), thickness of the cortex (µm), thickness of the epidermis (µm) and the thickness of the endoderm (µm) and at the base of the minicuttings, phloem thickness (µm), cortex thickness (µm), sclerenchyma ring thickness (µm) and number of sclerenchyma ring spaces were measured. Data were submitted to the Shapiro Wilk test (p>0.05) and Bartlett (p>0.05). Analysis of variance was performed (p<0.01 and p<0.05). The means were compared using the Tukey test (p<0.05). The ministumps showed 100% survival during 844 days of successive collections of shoots, which indicated high longevity for the three cultivars. The highest minicutting production, survival and rooting occurred in the summer, spring and autumn seasons respectively. The cultivar that stood out in response to all variables was 'Koroneiki' showing superior results at all times of the year. In general, the concentration of Ca in solutions 2, 4, and 6 ml L -1 induces greater survival and rooting, the greater number of roots, greater dry mass for the three cultivars. And better anatomical features of the root for ‘Grappolo 541’ and the mini- cuttings for ‘Koroneiki’. The application of IBA positively influenced rooting and induced more robust rooting, although it was not a condition for rooting in the three cultivars. The clonal minigarden and minicutting with the use of nutrient solutions proved to be a viable technique given the need for fast, economical and efficient production of olive tree seedlings during all seasons of the year, understanding the growing increase in planting in subtropical and temperate regions in Brazil and others countries.