Monitoring the Green Vegetation Period of Two <i>Narcissus</i> Taxa by Non-Destructive Analysis of Selected Physiological and Morphological Properties

Abstract

In a pot experiment, an early-flowering Narcissus pseudonarcissus cv. ‘Dutch Master’ (DM) and late-flowering N. poeticus cultural form (PO) were examined. The photosynthetic rate (A), transpiration rate (E), stomatal conductance (gs), photosynthetic water use efficiency (WUE), relative chlorophyll content (CCI) and chlorophyll fluorescence (F) were measured regularly. Leaf length, scape length and weight of the plant organs were also measured. The DM cultivar had higher gs and lower E values than the PO on most measuring dates (season average: gs: DM: 165.34, PO: 123.63; E: DM: 1.39, PO: 1.78 mmol H2O m−2s−1). The A curve was similar for the two taxa, except for the first measuring dates. The basic F values (F0, Fm, Fv) for DM were lower and CCI values were higher than for PO (season average of CCI: DM: 94.82, PO: 60.34). The Fm/F0, Fv/F0 and CCI curves were well described by a second order equation. The seasonal change of F and CCI values was the greatest for both taxa near the leaf tip. Bulb growth occurred in the two taxa in approximately the same calendar period, regardless of flowering time. A significant part of the leaf growth in DM occurred after flowering, while the leaves of PO reached their mature size by flowering.

Keywords

• <i>Narcissus poeticus</i>
• <i>Narcissus pseudonarcissus</i>
• photosynthesis
• transpiration
• stomatal conductance
• chlorophyll fluorescence