Fertilizantes organominerais líquidos como atenuadores da salinidade da água durante a formação de mudas do maracujazeiro-amarelo

Abstract

The passion fruit crop has great socioeconomic expression for a semi-arid region in the Brazilian Northeast, this is due to the good acceptability of the fruits and because it offers fast economic return, especially for medium and small farmers in the semi-arid Northeast. However, in this region, the salinity of water and soil has affected crop production. In this sense, the objective of this work was to evaluate the action of organomineral fertilizers via the leaves and via the soil in the attenuation of water and soil salinity during the formation of yellow passion fruit seedlings. The treatments were distributed in randomized blocks with three replications and four seedlings per plot, using a factorial scheme (2 × 3 × 2), referring to irrigation with non-saline (0.18 dS m-1) and saline (4.00 dS m-1), with application of organomineral fertilizers, codasal®, aminoagro-raiz® and a mixture of codasal® + aminoagro-raiz® (equal volumes 1 / 1), via spraying and via fertigation, at 10 and 40 days after emergence. The biometric variables evaluated were plant height, stem diameter, number of leaves, leaf area, root, stem, leaf and total dry matter, root volume and Dickson quality index. The physiological variables evaluated were chlorophyll fluorescence, chlorophyll a index and gas exchange. At the end of the experiment, substrate salinity was determined by the electrical conductivity of the saturation extract. The level of soil salinity was high, regardless of the organomineral fertilizer and the form of application, but with greater intensity in seedlings irrigated with 4.0 dSm-1 water. Chlorophyll index and photochemical efficiency unaffected by increased salt concentration in irrigation water. Stem diameter and leaf area were the morphometric measurements that had growth inhibited by the salts of irrigation water. Competent inputs did not attenuate the salinity effects of irrigation water and soil.