Response of Chloris gayana cultivars to salinity. 1. Germination and early vegetative growth

The effects of salinity on germination, vegetative growth, regrowth after clipping, osmotic adjustment and ion accumulation were evaluated in 6 cultivars of Chloris gayana at the early stages of growth. Two tetraploid cultivars, Boma and Callide, and 4 diploid ones, Bell, Katambora, Pioneer and a local accession of Pioneer, were included in the study. The rate of water uptake in seeds was not affected by salinity (0–400 mM NaCl); however, saline solutions delayed or altogether inhibited germination. Nevertheless, seeds of all the cultivars tested retained viability in 100 and 200 mM NaCl solutions, and germination percentages achieved after transfer to distilled water were not lower than 60%. Growth in all the cultivars was reduced at high salinities and cv. Boma was the most sensitive. This cultivar also had relatively lower Na and higher K accumulation in leaf tissues, and lower Na excretion via salt glands, than the other cultivars analysed.