Propagação vegetativa do vinhático (Plathymenia foliolosa Benth) por miniestaquia

Abstract

This work had as main objective the study of vegetative propagation via mini-cutting vinhático and specific objectives: 1) evaluate the germination of six progenies of Plathymenia foliolosa; 2) Evaluate the production and survival of the mini-stumps in mini-clonal hedge; 3) evaluate the effect of reduction of leaves of mini-cuttings on rooting and seedling growth of progenies of Plathymenia foliolosa by mini-cutting; and 4) evaluate the type influence of mini-cuttings and the effects of doses of IBA on rooting Plathymenia foliolosa. Plants originated from the propagation of seminiferous were used as mini-stumps and six seed progenies of vinhático (Plathymenia foliolosa Benth) collected from Laranjal (P01), Reduto (P03), Braz Pires (P19), Porto Firme (P21), Ponte Nova (P45) and Amparo do Serra (P53) municipalities were used. The seeds were pre-treated with sulfuric acid for 10 minutes and then taken to germinate. At 30 days after germination, the germination rate was evaluated. The clonal mini-hedges consisted of mini-stumps in semi-hydroponic system, obtained by seminiferous propagation from six progenies of Plathymenia foliolosa. The seedlings were transplanted at a spacing of 10 x 10 cm, containing a total of 96 mini-stumps per progeny. The mineral nutrition of mini-stumps consisted of drip fertirrigation applied three times daily at a total daily flow rate of 4 L m -2 . Mini-cuttings form apical part were used to evaluate the influence of leaf reduction on rooting of vinhático with 10 cm long, with treatments consisting of 100% reduction of leaf (without leaf), with 75% reduction of leaf and treatment without leaf reduction. The rooting of the shoots was performed using a remaining term of the plant material in the acclimatized greenhouse for 60 days, with acclimation in shade house for 15 days, followed by transfer to the area of full sun, where it was made a final assessment for the cuttings at 90 days. To evaluate the application of IBA at doses (0, 20.000, 40.000 and 60.000 mg L -1 ) and types of mini-cuttings (apical and intermediate), the cuttings remained 100 days in the greenhouse. The P19 and P03 progenies had the highest germination rates (88,3 % and 87,7 %, respectively) and P01 (54,8 %) and P45 progeny (47,7%) had the lowest values obtained. As for the survival of mini-stumps in clonal mini- hedges after the fourth successive cuttings collection, P3 and P19 progenies showed the highest survival percentages (64,5 % and 61,5%, respectively), while progeny P1 (32,3 %) and P45 (25%) showed the lowest values observed for this evaluation. The average number of mini-cuttings/mini-stump/collection produced ranged from 0.83 (progeny 53) to 4.8 (progeny 01), and the average productivity of 120 m2 mini-stumps mini-cuttings per collection. As for the influence of reduction of leaves of adventitious rooting in mini-cuttings, foliar treatments without reduction and 75% reduction showed no significant differences, however, 100% mortality was observed when the mini-cuttings had total reduction in leaves. Based on the results, it can be concluded that: progeny showed heterogeneity in the rate of germination; Progenies showed different responses to the productive potential of mini-stumps in successive collections of cuttings. The maintenance of the leaves is important for the survival and rooting of mini-cuttings, especially the reduction of non-leaf mini-cuttings, mainly due to the operational usability and optimization time. The survival of the mini- cuttings was influenced by its type and by the implementation of AIB.