Impact of nutrient solution concentration and growth period on baby leaf purslane production in floating system

This study was conducted in a greenhouse during the winter-spring of 2016-2017 as two successive periods, and aimed to determine the effects of nutrient solution concentrations on baby leaf purslane (Portulaca oleracea L.) production in floating system. Cultivation was carried out in seedling trays placed on aerated nutrient solutions and seeds were sown into peat. Each seed was sown into each hole (17 mL) of trays having 210 cells in each (957 plants m‑2). Following germination in the germination chamber, seeds were moved to climate controlled greenhouse. After emergence, seedlings in trays were placed onto water culture on December 7, 2016 for the 1st period and on March 10, 2017 for the 2nd period. Two nutrient solution doses as 1) “full dose” (complete nutrient solution) and 2) “half dose” (50% reduced macro-nutrients of full dose) and “water” (without nutrients) were applied. Plants were harvested when they reached to 12-15 cm in length, and harvested 3 times in both periods. Findings of the study showed that plant growth, yield and quality varied depending on the concentration of nutrient solution as well as the temperature during the growing period. When the temperatures were higher, yield increase and earliness were achieved. Although yield values decreased when the concentration of nutrient solution decreased, there were no significant differences between full and half dose treatments in many measured parameters. As the nutrient solution concentration decreased, vitamin C content increased and nitrate content decreased. Leaf N, P, K and Fe contents decreased with decrease in the nutrient solution concentration, whereas Ca contents increased. It was concluded that baby leaf purslane can be grown in a floating water culture resulting in a reduction in nitrate content and half-dose could be applied considering yield, however, growing period should be taken into account due to the higher yield and quality in spring season.