H.C.M. de Stigter, A.G.M. Broekhuysen
The beta-ray gauge technique offers a possibility to non-destructively determine specific fresh-leaf weight (i.e., fresh weight per unit leaf area). Multiplying by leaf area results in a reliable estimate of total foliage weight. By periodically repeating the procedure, one can follow foliage weight in time, with the leaves remaining intact on the stem throughout.

Comparison of these foliage weights with concurrent total shoot weight enables the relative contributions to be assessed of flower and foliage to fresh-weight patterns in cut and intact rose shoots previously reported.

Results obtained, so far, with intact roses and with cut roses standing in water or in glucose-containing solutions indicate that weight changes are mainly caused by the bloom throughout the flowering period, with a relatively minor, but more or less constant contribution from the foliage.

Differentiation between overall weight trends and the diurnal rhythms results in a more dynamic picture. The course of overall weight is apparently governed by the dynamics of flower-bud unfolding and subsequent development. The diurnal weight fluctuations, however, reflect the changes in water status of both petals and foliage. Here too the effect of the petals dominates that of the foliage, initially, but increasingly less so toward the end of the blooming period.

The general conclusion is that the techniques used allow detailed analysis of the dynamic behaviour of cut roses in variously composed vase solutions.

de Stigter, H.C.M. and Broekhuysen, A.G.M. (1983). RELATIVE CONTRIBUTIONS OF FLOWER AND FOLIAGE TO FRESH-WEIGHT PATTERNS IN CUT ROSES. Acta Hortic. 138, 277-284
DOI: 10.17660/ActaHortic.1983.138.32

Acta Horticulturae