Leaching of salts and production of sour passion fruit irrigated with low- and high-salinity water

Abstract

The objective of this study was to evaluate the effect of irrigation with low- and high-salinity water on the increment of salts in the soil, the production components of sour passion fruit and the leaching of salts by rainfall and by leaching fraction of 10%. The treatments were arranged in randomized blocks, in a split-plot scheme, corresponding to three irrigation management practices [evaluation of soil chemical attributes before irrigation; and after irrigation with water of low electrical conductivity (0.35 dS m-1), and high electrical conductivity (4.00 dS m-1) in the main plot], and in the subplot two soil depths of evaluation (0-20 and 20-40 cm) and three soil sampling times (at 115 days after transplanting of seedlings (DAT) - beginning of flowering; at 199 DAT - end of the dry season; and at 379 DAT - end of the rainy season). Irrigation increased the electrical conductivity of the soil saturation extract, with higher values in the surface layer and at the end of the dry season. Rainfall during the rainy season reduced the saline character of soil from moderately saline and strongly saline, in treatments irrigated with water of low and high electrical conductivity, to non-saline and slightly saline, respectively. Irrigation with high-electrical conductivity water negatively affected the production components and yield of sour passion fruit.

NPK Accumulation, Physiology, and Production of Sour Passion Fruit under Salt Stress Irrigated with Brackish Water in the Phenological Stages and K Fertilization

“…Furthermore, excessive ion concentrations in the soil solution also damage photosynthetically active leaves and can result in chlorosis and early senescence, thus negatively affecting photosynthetic efficiency and production [ 4 ]. In this context, several studies have been carried out evaluating the effects of irrigation with saline water in the passion fruit crop, highlighting changes in gas exchange [ 5 ], photochemical efficiency [ 6 ], synthesis of photosynthetic pigments [ 7 ], and membrane instability [ 8 ], as well as a reduction in production components [ 9 , 10 ] and post-harvest quality [ 11 ]. However, these studies are restricted to the use of water with different levels of salinity throughout the plant development cycle, thus requiring further research, especially to assess the effects of salt stress on the accumulation of NPK, physiology, and production of sour passion fruit plants of the cultivar BRS GA1, one of the most commonly grown in northeast Brazil, at varying phenological stages.…”

“…In this context, several studies have been carried out evaluating the effects of irrigation with saline water in the passion fruit crop, highlighting changes in gas exchange [ 5 , 22 ], photochemical efficiency [ 6 ], synthesis of photosynthetic pigments [ 7 ], and membrane instability [ 8 ], as well as a reduction in production components [ 9 , 10 ] and post-harvest quality [ 11 ]. However, these studies are restricted to the use of water with different levels of electrical conductivity throughout the plant development cycle, thus requiring further research, especially to assess the concentrations of NPK, physiology, and production of Passiflora edulis Sims, cultivar BRS GA1, grown under salt stress in the phenological stages and fertilization with K.…”