Leaf gas exchange of mango (Mangifera indica L.) cuttings during adventitious root formation.
Schaesberg N. von, Ebert G., Lüdders P.
Author Affiliation: Fachgebiet Obstbau, Institut für Nutzpflanzenforschung, Technische Universität Berlin, 1000 Berlin 33, Germany.
Angewandte Botanik 67 : 14-16
Abstract : Gas exchange during adventitious rooting of leafy cuttings was compared for the rootstock cultivars Terpentine (easy to root) and 13-1 (difficult to root). Net CO2 assimilation rates (NAR) and transpiration rates (E) were measured when the cuttings were still attached to the mother plant and after excision during root formation under intermittent mist. Under natural light conditions in the mist bed (photon flux density (PFD) = 100-200 µmol?m-2s-1), NAR and E of both Terpentine and 13-1 cuttings dropped after excision from the stock plant. Callus formation and subsequent rooting were accompanied by enhanced CO2 uptake by the leaves. This was not observed for cuttings that failed to root. Differences in photosynthetic activity of rooted and unrooted cuttings were more pronounced for 13-1 than for Terpentine. However, when a saturating light intensity (PFD = 1600 µmol?m-2s-1) was applied during measurement, the rise in NAR at the time of root emergence was much higher for Terpentine cuttings than for 13-1.