Salinity effects on perennial, warm-season (C4) grass germination adapted to the northern Great Plains

Schmer, M. R., Xue, Q. and Hendrickson, J. R. 2012. Salinity effects on perennial, warm-season (C-4) grass germination adapted to the northern Great Plains. Can. J. Plant Sci. 92: 873-881. Limited information is available on the germination of perennial C-4 grasses adapted to the northern Great Plains under saline conditions. Big bluestem (Andropogen gerardii Vitman), indiangrass [Sorghastrum nutans (L.) Nash], prairie cordgrass (Spartina pectinata Link), and switchgrass (Panicum virgatum L.) seeds were evaluated under non-saline and saline conditions corresponding to electric conductivity (EC) values of 0, 4, 8, 12, 16, and 20 dS m(-1), respectively. Ten cultivars were evaluated to determine salinity tolerance differences among and within species. Seeds were monitored for 21 d and analyzed for final germination percentage (GP), germination rate index (GRI), corrected germination rate index (CGRI), and germination velocity (GV). Differences among species were observed for all indices tested (P <0.01). Indices showed within species variation for big bluestem, indiangrass, and switchgrass. Big bluestem had the highest germination rates under increased salinity levels while prairie cordgrass had the lowest germination rates under non-saline and saline conditions. Indiangrass showed higher seed germination than switchgrass under low EC levels (0 to 4 dS m(-1)) but declined at a higher rate when EC levels exceeded 16 dS m(-1). Results from this study suggest grassland reestablishment from seed on variable saline soils will be dependent on both the species chosen and the specific cultivar used.