Adubação de pré-plantio no crescimento, produção e qualidade da amoreira-preta (Rubus sp.)

Abstract

Blackberry is a temperate climate fruit that due to its rusticity, good yield, fast economic feedback and several options of market, it is a good alternative for small farms diversification. The objective of this work was to assess the effect of seven different pre-planting fertilizers on blackberries cultivars Tupy and Xavante. The experiment was carried out at the city São Mateus do Sul Paraná state, in 2006 and 2007 crop. The applied treatments were: T1: Control; T2: 2.0t/ha of broiler litter (BL); T3: 350kg/ha of the composition 8-20-20 (recommendation of CQFS-RS/SC, 2004); T4: 2.0t/ha of BL+1.2t/ha Thermophosphate (TP)+2.0t/ha lime-schist (CX)+1,0t/ha schist (spent-oil shale) (XR); T5: 2.0t/ha BL+1.2t/ha TP+1.0t/ha CX+0.5t/ha XR; T6: 2.0t/ha BL+1.2t/ha TP+4.0t/ha CX+2.0t/ha XR and T7: 2.0 t/ha BL+1.2 t/ha TP. The responses variables measured were shoots number per plant, shoot diameter, relation between shoot number and yield, pruning dry matter (PDM), yield, dynamic of production, Agronomic Efficiency Index (AEI), weight, diameter, total soluble solids (TSS), color, anthocianyn content, fruit acidity percentage, nutrient exportation and some content of macro and micronutrients in the pruning material, fruits and soil. The results were analysed using the statistical software WinSTAT version 2.11 at 5% level of significance. It was verified significative effects of the treatments using pre-planting fertilization only at the soil nutrients content; T6 and T3 showed the highest phosphorus and potassium concentrations, respectively. The cultivar Tupy was statistically superior at the variables PDM, yield, diameter and fruit weight and anthocianyn content. Also, there were high concentrations of Ca, Mg, Cu, Fe and B in the pruning material and K, P and Cu in the fruits. Xavante was superior in shoot density and fruit color, as well as in the concentration of Ca and Mn in fruits. The cultivars Tupy and Xavante did not statistically differ at the variables: shoot diameter, TSS and fruit acidity. Also the content of P, K, S, Zn and Mn in the pruning material and B, Fe, Mg and S in the fruits did not change. There was a positive correlation of 93% for Tupy and 84% for Xavante between the increase of shoot number and yield. The harvest period extended during 71 days, being the effective harvest period (90% of production) 37 days for cv. Tupy and 24 days for cv. Xavante. The AEI of Tupy was higher in T3 and of Xavante in T5. The treatments of pre-planting fertilization did not promote alterations on nutrients content to be about to induce significative variations of the assessed variables. Regarding to cultivars, Tupy showed superior results compared to Xavante in the main studied variables.