In a protected environment, applying excess fertilizer
and using water with soluble salts cause soil salinization
due to the absence of lixiviation by precipitation. Among
commercial vegetables, beets (
Beta vulgaris
L.) have
good tolerance to soil salinity, being a good option for
growth under these conditions. An experimental study was
carried out in the municipality of Botucatu, São Paulo,
Brazil. The treatment consisted of a combination of the
following factors: initial soil salinity (1, 3, 6, 9, and 12 dS
m-1), fertigation management (traditional vs. control of ion
concentration of the soil solution) and two beet cultivars
(‘Early Wonder’ and ‘Itapuã’) in a 5 × 2 × 2 factorial
design. A randomized block design with four replicates
was adopted, totaling 80 experimental plots. The total fresh
weight of aerial part and root, total dry weight of aerial part
and root, and water use efficiency (WUE) were assessed.
Significant differences were found between fertigation
management practices and salinity levels proposed. ‘Itapuã’
showed better yield and WUE for electrical conductivity
(EC) below 6 dS m
-1. Under traditional fertigation, root
yield response fits a linear model with a decrease of
11.365 g (‘Early Wonder’) and 11.025 g (‘Itapuã’) for
each unit increase in EC. Under controlled fertigation, the
best-fit model was quadratic, with maximum estimates of
248.83 g for ‘Early Wonder’ and 258.52 g for ‘Itapuã’.
Controlling EC of the soil solution had a positive effect,
while salinity levels above 6 dS m
-1 must be avoided.
