Irrigation strategies with brackish water in the cultivation of Italian zucchini under potassium fertilization

Zucchini may present different responses to the presence of salts in its phenological phases, and the supply of potassium can interfere with assimilate allocation dynamics, maximizing production. In this context, the aim of this study was to evaluate the effect of brackish water irrigation strategies at different phenological stages under potassium fertilization on the yield and quality of italian zucchini fruits. A completely randomized design was adopted in a 4 x 3 factorial scheme, with the application of different irrigation strategies (S1, S2, S3 and S4) based on crop phenology using two electrical conductivities (ECw) (W1: 0.3 dS/m; W2: 2.6 dS/m). (S1= W1 throughout the crop cycle; S2= W1 up to flowering and early fruiting, and W2 during the full fruiting and harvesting phases; S3= W2 during flowering and early fruiting, and W1 during full fruiting and harvesting; S4= W1 up to flowering and early fruiting, W2 during the full fruiting phase, and W1 during harvesting), with three potassium doses (K1= 0, K2= 7.5, and K3= 15 g/plant), and four replications. Saline stress at any stage reduces fruit quality, in addition to resulting in lower productivity and water use efficiency. Doses of 50 (K2) and 100% (K3) potassium provided lower productivity and water use efficiency. Further analyses and research are required to determine the ideal dose for crops under similar conditions of this study.