Abstract
For the purpose of quantitatively distinguishing the influences of temperature (t), humidity (h), leaf position in a tobacco stalk (p) and direction in a leaf, upon the tensile characteristics or equilibrium moisture content of tobacco (Y), statistical calculations were carried out with many data on typical varieties in Japan, that is, Flue-cured (v1) and Domestic variety (v2). And the following formula to estimate Y was analyzed (Table III).
Y=C0+C1t+C2h+C3h2+C4p+C5p2
After that, the relation between tensile characteristics and equilibrium moisture content (w) was searched with the formula Y.
The important results obtained were as follows:
(1) Tensile strength (Pm)
The Pm of v1 was greater than that of v2. The Pm of v1 was decreased when the h(w) or t was increased, but the Pm of v2 did not show any notable tendency with the h (w) or t. In every variety the Pm was decreased toward the lower position in a stalk (Fig. 3 and 4).
(2) Elongation percentage (ε)
The ε of v1 was higher than that of v2. In every variety the ε was increased when the h (w) or t was increased, and toward the upper position in a stalk (Fig. 3 and 4).
(3) Elastic modulus (E) and Elasticity per unit dry weight (EG)
The E of v1 was smaller than that of v2. In every variety the E was decreased when the h (w) or t was increased. In the variety v1 the E became minimum at the upper or middle position of a stalk, and was increased toward the lower position. This tendency was shown in the variety v2 too, but the degree of change with the stalk position in the v2 was smaller than that in the v1. The appearance of the change in the EG was very similar to the above-mentioned results in the E (Fig. 5 and 6).
(4) The influence of w on tensile characteristics (Pm, ε, E or EG) was very much greater than that of t (Fig. 4 and 6).
