Drought Tolerance of Seminal Lateral Root Apices in Crested Wheatgrass and Russian Wildrye

Abstract

Germinating seed of crested wheatgrass (Agropyron desertorum) and Russian wildrye (Elymus junceus) were exposed to temporary drought, and the capacity for development of seminal lateral roots was then determined under conditions of favorable soil moisture. After a temporary drought of -370, -910, and -1580 bars, 75, 58, and 24% of the crested wheatgrass seedlings and 69, 20, and 6% of the Russian wildrye seedlings developed seminal lateral roots, respectively. Because actively growing seminal primary roots may be killed by temporary drought and because germinating seed and young seedlings lack the capacity for development of adventitious roots, the growth and survival of seedlings often may depend on the development of seminal lateral roots.