Propriedades do solo, crescimento, composição mineral e produção do maracujazeiro amarelo em função da água salina, potássio e biofertilizante bovino

Abstract

Passion fruit is one of the main fruit grown in Brazil and especially in the Northeast by favorable environmental conditions and economic value. In this region the same irrigation with restricted water use has become necessary to maintain adequate production levels, as well as chemical and organic fertilization. In this regard it was held July 2013 experiment to May 2014, seeking to assess the effects of salinity of the water, biofertilizer and bovine types of potassium, in the fertility and soil salinity, growth, mineral composition, gas exchange and production of BRS giant yellow passion fruit. The treatments were arranged in a randomized block design with three replications and 12 plants per plot with factorial 2 x 2 x 2, referring to the electrical conductivity values of irrigation water of 0.35 and 4.00 dS m-1, in the soil with and without bovine biofertilizer and fertilization with two sources of potassium (K2O 60 %), conventional potassium chloride and coated with organic polymers to slow the potassium release during plant growth. The holes were opened in the dimensions 40 x 40 x 40 cm, spaced planting 3 m 2.0 m between plants and between lines. The Irrigation with each type of water was performed every 48 hours with two drip emitters per plant, with a flow rate of 10 L h-1. Were evaluated the fertility were assessed, salinity, moisture and soil temperature, height growth, transplanting period pruning of the main stem and will prune the lateral branches, number of branches to 100 DAT, diameter, mineral composition of plants in macro and micronutrients , gas production and exchange. The irrigation with saline water reduces the average magnesium content in the layer of 21-40, potential acidity, CTC and provided increases in content edafic sodium, Saturation percentage for bases at 0-20 cm, electrical conductivity of the saturation extract in plant flowering period at the end of the drought, the rainy season and foliar nitrogen, iron and sodium. The biofertilizer contributed to the increase in phosphorus, calcium in the layer of 21-40 cm, magnesium and sodium in the 0-20 cm layer, sum of bases, potential acidity, soil organic matter, moisture and soil, soil electrical conductivity, but kept the PST values without sodicity risks, stimulated the growth of plants even in soil irrigated with saline water and foliar phosphorus and zinc, but reduced the foliar sulfur content. The fertilization with coated KCl provided increases in potassium levels, percentage of base saturation and soil organic matter in the 21-40 cm layer, pH of the soil saturation extract at the end of the dry season in the layer of 21-40 cm and rainy 0-20, stimulated the growth of plants irrigated with highly saline water and leaf boron content, but provided a reduction in potassium levels and manganese in comparison conventional KCl. Despite being in nutritional levels lower than recommended, the plants showed satisfactory levels of production components.