Production of guava seedlings with increasing water salinity and nitrogen- potassium fertilizations

Salt stress affects the development of several crops, being one of the limiting factors for irrigated agriculture in the semiarid region, where nitrogen and potassium fertilization can be an alternative for agricultural production. This study aimed to evaluate the viability of using water with different salinities associated with varying amounts of nitrogen and potassium fertilization in the production of seedlings of the guava cultivar Paluma in an experiment conducted in experimental areas of the Federal Rural University of the Semi-arid Region (UFERSA), campus of Caraubas. The research was carried out from February to June 2021. The study was set up in a randomized block design and analyzed in a 5 x 4 factorial scheme with four replicates, and two plants per plot. Treatments were established by combining different levels of electrical conductivity of the irrigation water (ECw): 0.3, 1.1, 1.9, 2.7, and 3.5 dS m-1, with Combinations (C) of nitrogen (N) and potassium (K2O) levels of recommended fertilization: C1 = 70% N + 50% K2O, C2 = 100% N + 75% K2O, C3 = 130% N + 100% K2O, and C4 = 160% N + 125% K2O. Irrigation with electrical conductivity levels up to 2.1 dS m-1 favored seedling growth for the guava cv. Paluma. Fertilization combinations C1 and C2 promoted the greatest increases in growth and biomass for guava seedlings cv. Paluma 125 days after sowing. Fertilizer combinations did not mitigate the harmful effects of salt stress from irrigation water on the production of young guava cv. Paluma.

Automated summary

Salt stress can impact crop development, but nitrogen and potassium fertilization can be an alternative for improving agricultural production in semiarid regions. This study evaluated the viability of using water with different salinities, combined with varying levels of nitrogen and potassium fertilization, for guava seedling production. The results showed that irrigation with electrical conductivity levels up to 2.1 dS m-1 favored seedling growth. Fertilization combinations C1 and C2 promoted the greatest increases in growth and biomass. However, fertilizer combinations did not mitigate the harmful effects of salt stress on guava seedling production.