The Response of Portulaca oleracea L to Different Concentration of Nitrogen Fertilizer

The growing responses of Portulaca oleracea L. to nitrogen fertilizer stress caused by different concentration of urea applications were studied. The study was to determine not only the most appropriate nitrogen form but also the effect of these forms on growth, yield, element content and nitrate accumulation of cultivated purslane (Portulaca oleracea L.) when the usual N dose was applied. For this purpose, 20 seeds of mentioned species were placed on plastic pots in each replicate and irrigated with (control), N1, N2, and N3 of urea fertilizer. The results indicated that urea effects were significant (P < 0.05) for seed germination and plant height and number of leaves. The greater amount of fertilizer application reduced the plant height and number of leaves that means P oleracea L. is very sensitive to urea as salt causing salinity. Considering the nitrate accumulation in leafy vegetables is harmful for human health, therefore, the usual dose of ammonium sulfate is firstly suggested that it should be applied to not only have better yield and agronomic traits but also produce healthy crops for human nutrition in cultivated purslane. However, when the highest yield was taken into consideration, ammonium nitrate was also suggested as a fertilizer for purslane