Potassium and irrigation water salinity on the formation of sour passion fruit seedlings

The high concentration of salt in the waters of the semi-arid region of Northeast Brazil is a limiting factor for agricultural production in the region. In this context, the objective of this study was to evaluate the percentage of cell membrane damage, contents of photosynthetic pigments and growth of sour passion fruit seedlings, cv. BRS RC, under irrigation with saline water and potassium fertilization. The experiment was conducted in a greenhouse, adopting a randomized block design in a 5 x 2 factorial arrangement, with five values of electrical conductivity of irrigation water (0.3; 1.1; 1.9; 2.7 and 3.5 dS m(-1)) and two potassium doses - KD (50 and 100% of the fertilization recommendation for pot experiments), with two plants per plot, and four replicates. The dose referring to 100% of the recommendation corresponded to 150 mg of K2O kg(-1) of soil. Water salinity from 0.3 dS m(-1) promoted reduction in the chlorophyll synthesis and growth of seedlings of sour passion fruit cv. BRS RC. Despite the reduction in growth, water with electrical conductivity of up to 3.5 dS m(-1) can still be used to form passion fruit seedlings with acceptable quality for the field. Potassium does not attenuate the deleterious effects of salt stress on the formation of seedlings of sour passion fruit cv. BRS RC.

Automated summary

The high salt concentration in the waters of the semi-arid region of Northeast Brazil limits agricultural production, affecting chlorophyll synthesis and growth of passion fruit seedlings. However, water with electrical conductivity up to 3.5 dS m(-1) can still be used to produce seedlings of acceptable quality. Potassium fertilization does not mitigate the deleterious effects of salt stress on the formation of passion fruit seedlings.