A model of the growth of leaves of begonia hiemalis fotsch. grown in long days and with intercalated short days
Powell, M.C.; Bunt, A.C.
Journal of Horticultural Science 61(4): 523-532
1986
Accession: 004587808
The validity of several functions of Gompertz, logistic and Richards types, as descriptions leaf growht in Begonia .times. hiemalis in long days and with an intercalated period of short days was assessed on the basis of three criteria: (1) goodness of fit, (2) ability of extrapolated values representing primordial length to simulate bud structure when curves are stacked in sequence, and (3) the credibility of estimated leaf initiation sequences from extrapolated curves. The best fit for plants grown in long days was obtained by a Richards-type function with a curved asymptote and further modified to reflect ontogenetic drifts in some parameters. For plants transferred to short days for eight weeks the model was less appropriate. Problems arose from inadequate data from leaves with greatly inhibited growth and the failure of these mathematical functions to described discontinuous growth.