Effect of water regime and salinity on artichoke yield

This work focuses on the effects of different salinity and water inputs on the yield of artichoke Violetto di Provenza. Two years of experimental works had been carried out in a site in Southern Italy characterized by semi-arid climate and deep loam soil. Three salinity levels of irrigation water (S0, S1 and S2) with electrical conductivity (ECw) of 0.5, 5 and 10 dS m-1, respectively, were combined with three water regimes (W1, W2 and W3) corresponding in that order to 20 40 and 60% of available water depletion. The overall results of the salinity tolerance are in agreement with those from the literature. However, an higher tolerance to salinity was demonstrated when crop was watered more frequently (at 20% of available water depletion) and a lower one when crop watering was performed less frequently (at 60% of available water depletion). The increase of salinity level reduced marketable yield (from 12.9 to 8.8 Mg ha-1), total heads (from 125,100 to 94,700 n ha-1) and heads mean weight (from 99.9 to 94.6 g), while increased heads dry matter (from 161.8 to 193.6 g kg-1 f.w.) and reduced edible parte percentage of heads (from 35.2 to 33.2 %). Watering regimes, as average of the salinity levels, affected total heads marketable yield (115,350 n ha-1 and 11.4 Mg ha-1 for W1 and W2, 105,900 n ha-1 and 10 Mg ha-1 for W3). In addition, different watering regimes affected the secondary heads yield for which it was reduced by 3% of mean weight. The effect of different watering regimes changed with various salinity levels. In condition of moderate salinity (S1), maximum water depletion fraction to preserve heads number and weight yield was 40 and 20% of total soil available water, respectively. However, with high salinity (S2), maximum water depletion fraction to keep unchanged heads number and weight yield was 20% for both. The level of soil salinity at beginning of the crop cycle favoured the incidence of head atrophy in the main heads produced in the second year.