Influence of altitudinal gradient on some physiological and ecological aspects of solanum incanum L. growing naturally in Yemen

الملخص EN

The study aimed to clarify the effect of altitudinal gradient on some physiological and ecological characters of Solanum incanum L.

growing naturally in Yemen.

The plant samples were collected from four locations ranging in altitude from 1570-2595 meters above sea level in two seasons (Winter and Summer of2000).

Results indicated that locations 1 and 2 (1570 and 1800m) had a higher monthly temperature than the other elevations.

Moreover, location 3 (2200 m) showed the lowest value of relative humidity.

In addition, location 2 had the highest amount of rainfall.

The soil associated with S.

incanum at the highest altitude (2595 m) was characterized usually by the highest values of soil moisture content, EC, K and total anions during the two studied seasons.

Additionally, soil of location 3 generally had the maximum amounts of Na, Ca, Mg, Cl as well as total cations in both seasons It was found that as altitude increased, K, Ca, Mg, total reducing value (TRV) and protein-N content were increased in the stem of S.

incanum during winter, while protein-N and total–N contents were increased in summer.

Moreover, total soluble-N content decreased in the two studied seasons.

In the leaves, with increasing altitude, polysaccharides, total carbohydrates and total soluble-N content were usually lower in winter.

In addition, reducing and total soluble sugars values in leaves were increased during summer with increasing altitude.

Compared with the lowest altitude, TRV value in fruits of S.

incanum increased during winter, however, Mg, Fe, polysaccharides, protein-N and total-N contents decreased in winter.

Also, high solasodine content was detected in fruits of S.

incanum at the highest altitude during winter.

The result of the gel electrophoretic technique showed that more proteins were synthesized in abundance in the medium elevations.