Am. Markarov et Tk. Golovko, GROWTH ORIENTATION OF UNDERGROUND SHOOTS IN PERENNIAL HERBACEOUS PLANTS .3. MORPHOPHYSIOLOGY OF UNDERGROUND SHOOTS AND SARMENT DEVELOPMENT, Russian journal of plant physiology, 42(5), 1995, pp. 630-634
The growth orientation and development of underground shoots producing
sarments were studied in a series of tuberous plants including Solanu
m demissum Lindl., S. acaule Bitt., S. molinae Juz., Helianthus macrop
hyllus Willd., and Ullucus tuberosus Caldas. Morphophysiological prope
rties of sarments as compared to rhizomes and stolons, were identified
. In the course of differentiation, the sarment apical zone produced l
eaf primordia during underground diatropic growth. Before light-depend
ent differentiation the sarment apex exhibited a negative phototropic
response mediated by the phytochrome system. Such phytochrome-mediated
control of diatropic growth orientation operated till the appearance
of leaf primordia. Leaf primordia formation completed the period of un
derground diatropic growth, then the shoot protruded through the soil,
occupied an above-ground orthotropic position and developed into the
plant.