Bell pepper production under saline stress and fertigation with different K+/Ca2+ ratios in a protected environment

Abstract

Bell peppers are sensitive to salinity; therefore, it is necessary to find alternatives to reduce saline stress. An experiment was conducted in a greenhouse at Federal Rural University of the Semi-Arid Region, in Mossoró, Rio Grande do Norte State, Brazil, to evaluate the effects of salinity and K+/Ca2+ ratios on bell pepper production. The experimental design consisted of randomized blocks in a 5 x 4 factorial scheme with four replicates, corresponding to five K+/Ca2+ ratios (F1 = 3.3/1, F2 = 2.8/1, F3 = 2.2/1, F4 = 1.8/1, and F5 = 1.5/1) and four salinity levels in the nutrient solution using NaCl (1.75, 3.25, 4.75, and 6.25 dS m-1). The following parameters were evaluated: the number of fruits (total, marketable and unmarketable), the mean weight of fruits (marketable and unmarketable), fruit production (total, marketable and percentage of marketable fruits) and a salinity tolerance index. Generally, nutrient solution enrichment with K+ or Ca2+ did not cause significant increments in bell pepper yield. The fertigation treatments F2, F3, and F5 led to a higher bell pepper tolerance to salinity, allowing waters with higher salt concentrations to be used without causing a reduction in the yield.

Electrical conductivity of the nutrient solution for soilless cultivation of kohlrabi

“…Horticultura Brasileira 40 (2) April -June, 2022 grow fruit vegetables, such as green pepper (Silva et al, 2020) and tomato (Santos et al, 2016), among others. However, recently, several researchers have been adopting this system to grow leafy vegetables (Oliveira et al, 2018;Targino et al, 2019).…”

Potassium nutrition as a strategy to mitigate salt stress in melon grown under protected cultivation

“…The increase in ionic K/Na ratio can act as a stress-tolerance mechanism, since the high Na content disturbs water absorption, besides damaging the photosynthetic apparatus (P. L. D. Morais et al, 2019). The K/ Na ratio is an important trait used by several authors to indicate the tolerance of plants to salinity (Gao, Yang, Wei, Huang, & Zhang, 2020;R. C. P. Silva et al, 2020a), with the more tolerant genotypes exhibiting low Na contents and, consequently, high K/Na ratios in their plant tissue.…”

“…fruit size and weight) in response to an increase in the K rate in the soil or in hydroponic cultivation (Oliveira, Silva, Medeiros, & Vieira, 2020;Nascimento, Nascimento, & Cecílio, 2020;Gratieri, Cecílio, Barbosa, & Pavani, 2013). Studies can be found on the application of K as a salt stress-mitigating agent in crops such as peanut (Chakraborty, Bhaduri, Meena, & Kalariya, 2016), eggplant (Santos et al, 2018) and bell pepper (R. C. P. Silva et al, 2020a). However, no studies have reported its effect on fruit production, yield and quality in melon.…”

Bell pepper germination and seedling’s parameters under different osmotic potentials

“…The increase in soil salinity is a recurrent problem affecting crops production in modern agriculture. This condition is worse in regions with low precipitation, irrigation with low-quality water, successive application of fertilizers and amendments with high salt content (Silva et al, 2020). The soil salinity effects on plants are usually related to the dynamics of water and nutrient absorption by roots and the toxic levels of some elements (Maciel et al, 2012;Oliveira et al, 2018;Sá et al, 2019).…”

“…Bell pepper is considered a salt-sensitive plant species (Silva et al, 2020); however, the productivity and the quality parameters of the bell pepper fruit could be improved by certain levels of deficit in irrigation, which highlights the importance of optimal irrigation management (Abdelkhalik et al, 2019).…”