Effect of aeration of the nutrient solution on the growth and quality of purslane (Portulaca oleracea)

The aim of this work was to assess the influence of three levels of aeration of the nutrient solution (high, low, or no aeration) on the growth and quality of two cultivars of purslane (Portulaca oleracea L.): the commercial cultivar, 'Golden Purslane', and a local Spanish accession, C-215. Both were grown in a floating system over four crop cycles. Our results showed purslane to be a crop that exhibited little sensitivity to oxygen depletion in the rooting medium, since it was able to adapt to a gradual reduction in oxygen content. Under such conditions, purslane plants created an aerenchyma tissue (equivalent to approx. 10% of root sections in the non-aerated treatments in both cultivars) that helped to maintain growth. Under conditions in which no aeration was provided, there was a slight decrease in plant growth.The final quality of the product was improved because leaf nitrate concentrations were reduced (by more than 1,300 mg kg-1 FW) compared with the high aeration treatment, and the content of functional phytochemicals and SPAD values (chlorophyll contents) were increased.