Mycorrhizal impact on osmotic adjustment in Ocimum basilicum during a lethal drying episode

Arbuscular mycorrhizal symbiosis can Improve drought avoidance capabilities of plants, but the actual dehydration tolerance of mycorrhizal and nonmyco rrhizal foliage has not been compared. In this study, leaves of mycorrhizal Ocimum basilicum plants developed lower, full-turgor psi (pi) than leaves of nonmycorrhizal plants during a lethal drought, indicative of greater act ive osmotic adjustment. This did not translate into increased drought resis tance, as lethal leaf psi lethal soil psi (m) and length of the lethal drou ght episode were not affected by the symbiosis.