Tomato Culture: A Practical Treatise on the Tomato

Excerpt

Botany of the Tomato

of our gardens belongs to the natural order Solanaceae and the genus Lycopersicum. The name from lykos, a wolf, and persica, a peach, is given it because of the supposed aphrodisiacal qualities, and the beauty of the fruit. The genus comprises a few species of South American annual or short-lived perennial, herbaceous, rank-smelling plants in which the many branches are spreading, procumbent, or feebly ascendent and commonly 2 to 6 feet in length, though under some conditions, particularly in the South and in California, they grow much longer. They are covered with resinous viscid secretions and are round, soft, brittle and hairy, when young, but become furrowed, angular, hard and almost woody with enlarged joints, when old. The leaves are irregularly alternate, 5 to 15 inches long, petioled, odd pinnate, with seven to nine short-stemmed leaflets, often with much smaller and stemless ones between them. The larger leaflets are sometimes entire, but more generally notched, cut, or even divided, particularly at the base.

FIG. 2—TOMATO FLOWERS ENLARGED ABOUT 2½ TIMES. SECTION OF FLOWER SHOWN AT RIGHT
(Drawn from a photograph by courtesy of Prof. L. C. Corbett)

are pendant and borne in more or less branched clusters, located on the stem on the opposite side and usually a little below the leaves; the first cluster on the sixth to twelfth internode from the ground, with one on each second to sixth succeeding one. The flowers (Fig. 2) are small, consisting of a yellow, deeply five-cleft, wheel-shaped corolla, with a very short tube and broadly lanceolate, recurving petals. The calyx consists of five long linear or lanceolate sepals, which are shorter than the petals at first, but are persistent, and increase in size as the fruits mature. The stamens, five in number, are borne on the throat of the corolla, and consist of long, large anthers, borne on short filaments, loosely joined into a tube and opening by a longitudinal slit on the inside, and this is the chief botanical distinction between this genus and Solanum to which the potato, pepper, night shade and tobacco belong. The anthers in the latter genus open at the tip only. The two genera, however, are closely related and plants belonging to them are readily united by grafting. The Physalis, Husk tomato or Ground cherry is quite distinct, botanically. The pistils of the true tomato are short at first, but the style elongates so as to push the capitate stigma through the tube formed by the anthers, this usually occurring before the anthers open for the discharge of the pollen. The fruit is a two to many-celled berry with central fleshy placenta and many small kidney-shaped seeds which are densely covered with short, stiff hairs, as seen in Figs. 3 and 4.

FIG. 3—TWO-CELLED TOMATO

FIG. 4—THREE-CELLED TOMATO

It is comparatively easy to define the genus with which the tomato should be classed botanically, but it is by no means so easy to classify our cultivated varieties into botanical species....