Seed Germination Strategies of Desmostachya bipinnata: A Fodder Crop for Saline Soils

Abstract

Desmostachya bipinnata (L.) Stapf. (Poaceae), or drub, a perennial grass of near-coastal and inland deserts, is a potential fodder crop for either saline soils or where only brackish water is available for irrigation. The responses of D. bipinnata seeds under various salinity (0, 100, 200, 300, 400, and 500 mM NaCl), temperature (10 degrees-20 degrees, 15 degrees-25 degrees, 20-30 degrees, and 25 degrees-35 degreesC) and light (12:12-h dark:light and 24-h dark) regimes were investigated. All seeds germinated under nonsaline conditions, however, increase in salinity resulted in a progressive decrease in germination, and few seeds germinated at 500 mM NaCl. Change in temperature had little effect on seed germination under nonsaline conditions, however, seed germination was inhibited under cooler saline conditions. The germination under saline conditions improved at warmer temperature regimes. Seed germination under nonsaline control in dark was similar to those of seeds germinated in light. However, at high salinities, seed germination was substantially inhibited in dark in comparison to those germinated in light. When ungerminated seeds were transferred to distilled water they germinated immediately, and those from higher salinity and temperature regimes had higher recovery. The ability of seeds to germinate over a range of salinity and temperature regimes suggests possibilities for sustainable use of this species as a cash crop in saline soils.