Sources of calcium applied in the soil and its relationship to the quality of 'Venus' grape/Fontes de calcio aplicadas no solo e sua relacao com a qualidade da uva 'Venus'

This work was conducted to evaluate the effects of different sources of [Ca.sup.2+], applied in the soil, on the content of this nutrient in the soil, in the leaves, and in the fruits; the physico-chemical attributes and the post-harvest conservation of grapes 'Venus' (Vitis labrusca x V. vinifera). The experiment was carried out in a random block design, with four replications. It was used the following treatments: T1--control (without application of [Ca.sup.2+] in the soil); T2--calcium chloride; T3--gypsum; T4--Nitrabor[R]; T5--hydrated lime; and, T6--cellulose paste. For all sources was applied the equivalent of 80 kg of [Ca.sup.2+] [ha.sup.-1], in three applications, every 21 days, starting on the leafing time. It was evaluated the content of nutrients in the soil, leaves and fruits. At maturity, four grape clusters were collected in each parcel, two of them were evaluated in the harvest and the other two ones were kept under ambient temperature and modified atmosphere, being evaluated after five days. In general, the sources of [Ca.sup.2+] promoted higher content of [Ca.sup.2+] in the soil, leaves and fruits. Nitrabor[R] and gypsum increased the average weight of berries. The sources of [Ca.sup.2+] reduced the loss of weight, the abscission and the incidence of fruits rot in post-harvest.