The effect of salinity on the growth, yield and essential oils of turnip-rooted and leaf parsley cultivated within the Mediterranean region

BACKGROUND: Turnip-rooted parsley, a field-crop of northern Europe, has recently been introduced to the Mediterranean region for fresh consumption or production of essential oil. Because of soil salinity within this area, the sensitivity of turnip-rooted and two other parsley subspecies (plain-and curly-leafed) to salt was studied. RESULTS: NaCl or CaCl2 additions to the irrigation water raised the electrical conductivity (EC) in increments from 0.5 dS m(-1) to 4.5 dS m(-1) (year 1) or 6.0 dS m(-1) (year 2), reducing parsley foliage weight in year 2, but increasing the root weight of turnip-rooted parsley in year 1. Raising the EC with NaCl increased the yield of foliar essential oil from curly-leafed parsley (both years), but not from the other cultivars. CaCl2 had less effect on oil yield. The relative concentrations of the principal aroma constituents (beta-phellandrene, myristicin, beta-myrcene and apiole) of the foliar essential oil were affected by NaCl or CaCl2 in a way that differed between cultivars. Oil yield from parsley roots was very low and apparently unaffected by salinity. CONCLUSION: All three parsley subspecies are moderately sensitive to salinity, but may be cultivated at <4.5 dS m(-1) EC. Salinity may assist oil production by increasing oil yield (curly-leafed parsley) and positively affecting certain aroma constituents. (C) 2009 Society of Chemical Industry