Adaptive Responses of Root Systems of Some Native and Cultivated Species to Desert Conditions

Study of the root systems of the wild species Plantago albicans, Rumex pictus and Cutandia dichotoma and the cultivated species Medicago sativa, Sorghum sudangrass and Hordeum vulgare indicated a maximum penetration to lateral root specialized species from 20 to 50 cm and from 25 to more than 110 cm in tap root specialized species. Root number increased with dryness while root length increased with wet conditions. This leads to low root length density for wild and irrigated cultivated species. Root/shoot ratio increased in the dry season as a result of shoot deterioration by water stress. Magneto tropism was recorded in the secondary branches of Plantago albicans roots.