Potassium fertilization in the cultivation of sour passion fruit under irrigation strategies with brackish water

In the Brazilian semiarid region, the occurrence of water sources with high salt concentrations stands out as a limiting factor for the production of most crops under irrigated conditions. This research was conducted to evaluate the physical and chemical quality of sour passion fruit as a function of brackish water irrigation strategies and potassium doses. The experiment was carried out under field conditions using a randomized block design in a 6 x 2 factorial scheme, consisting of six strategies of irrigation with brackish water (irrigation with water of 1.3 dS m(-1) throughout the cycle - WS; irrigation with water of 4.0 dS m(-1) in the vegetative stage - VE; flowering stage - FL; fruiting stage - FR; in the successive vegetative/flowering stages - VE/FL; vegetative/fruiting stages - VE/FR) and two potassium doses: 60 and 100% (345 g of K2O per plant per year) of recommendation, with four replicates and three plants per plot. Irrigation with water of 4.0 dS m(-1) in the flowering stage or continuously in the vegetative and flowering stages reduced the yield and size of sour passion fruit. Fertilization with 60% of K is recommended for the production of sour passion fruits with greater polar diameter. It is feasible to cultivate sour passion fruit under irrigation with 4.0 dS m(-1) of water in the flowering and fruiting stages and fertilization with 60% of the K recommendation without losses in ascorbic acid and total soluble sugars.

Automated summary

This research evaluated the physical and chemical quality of sour passion fruit under different saline water irrigation strategies and potassium doses. The results showed that continuous irrigation with water of 4.0 dS m(-1) in the flowering stage or throughout the vegetative and flowering stages reduced the yield and size of sour passion fruit. It is recommended to fertilize with 60% of potassium for producing sour passion fruits with larger polar diameter. Furthermore, it is feasible to irrigate sour passion fruit with water of 4.0 dS m(-1) in the flowering and fruiting stages and fertilize with 60% of the recommended potassium dose without losses in ascorbic acid and total soluble sugars.