Morphological and physiological differences between bareroot and container Juniperus excelsa seedlings

Abstract

The effects of stock type on morphological and physiological characteristics were compared in 1 + 0 Crimean juniper (Juniperus excelsa Bieb.) seedlings. In October 2010, the morphological characteristics of both stock types were determined. The physiological condition of both stock types was evaluated by measuring water relation, root growth potential (RGP), and root electrolyte leakage (REL) parameters in seedlings at periodic intervals from October 2010 to April 2011. Container seedlings had greater root collar diameter, higher height, and greater shoot dry weight than bareroot seedlings, but these differences were not significant. However, the shoot-to-root ratios of the container seedlings were significantly lower than those of the bareroot seedlings, but their root dry weights were higher. In both stock types, osmotic potential at turgor loss point, osmotic potential at full turgor, relative water at turgor loss point, apoplastic water fraction, symplastic water at saturated point per dry weight, dry weight fraction, RGP, and REL showed a seasonal variation. The differences between stock types in terms of the water relation parameters were not generally significant. The RGP values of the bareroot seedlings were higher than those of the container seedlings in January, February, and March, but their REL values were generally lower than those of the container seedlings on most lifting dates. For each type of stock, seedlings lifted in January and February had greater stress resistance than seedlings lifted in the autumn or spring. If the weather conditions are suitable, the safe period for lifting and planting is mid-January to mid-March.