F. Robert et G. Petel, Nucleotide synthesis capability as a marker of the petiole elongation of strawberry plants (Fragaria 3 ananassa Duch.), J HORT SCI, 75(6), 2000, pp. 690-696
Vegetative growth of strawberry plants, estimated by leaf blade and petiole
sizes, influences fruit development notably through carbohydrate synthesis
. Improvement in fruit production requires the control of internal and exte
rnal vegetative growth factors. For a better knowledge of the internal caus
es of vegetative growth, we evaluated cell elongation, cell size and cell n
umber in petioles of 'Elsanta' strawberry plants observed under natural con
ditions. Nucleotide synthesis potentialities of these petioles were also me
asured as well as adenosine kinase activity, an enzyme of the nucleotide me
tabolism. A growth area near the leaf blade was identified by these measure
ments. At the cellular level, elongation of petioles was a concomitant effe
ct of size increase and multiplication of cells which primarily took place
in the upper part of the petiole. Synthesis capabilities of nucleotide and
adenosine kinase activity were high at the beginning of petiole growth, whe
n cell development was important. The correlation established between these
morphological and biochemical measurements suggest that the measurement of
nucleotide synthesis potentialities and adenosine kinase activity could be
used as markers for vegetative growth of strawberry plants.