HIGHLIGHTS:
Rootstocks of Passiflora foetida can be considered salinity tolerant.
Irrigation of P. foetida rootstocks can be performed using water with electrical conductivity of up to 4.0 dS m-1.
The salinity tolerance of P. foetida rootstocks is associated with plant age.
ABSTRACT
Wild passion fruit species, due to the greater tolerance to environmental stresses, reveal potential as interspecific rootstocks. Passiflora foetida is a wild species potentially tolerant to salinity. Therefore, the objective with the study was to evaluate the effects of irrigation water salinity on the growth of wild passion fruit (P. foetida L.) rootstocks. The experiment was carried out in a protected environment. The treatments consisted of the electrical conductivity of the irrigation water (0.3; 1.0; 2.0; 3.0 and 4.0 dS m-1), distributed in randomized blocks. The assessments were performed at 7, 14, 21, 28 and 35 days after transplanting and consisted of: stem height and diameter, number of leaves, average leaf size, leaf area, and dry matter of shoots, roots and total. In younger rootstocks, the deleterious effects of salinity on height growth and leaf components were observed under lower electrical conductivities, with tolerance increasing with age. However, dry biomass accumulation was more severely restricted by salinity with increasing rootstock age. P. foetida rootstocks are salinity tolerant and can be irrigated with water of up to 4.0 dS m-1.
Key words:
wild passion fruit; water salinity; salinity tolerance