Ecophysiology of Pennisetum clandestinum: a valuable salt tolerant grass

High concentrations of sodium are toxic to most plant species, making soil salinity a major abiotic stress for plant productivity world-wide. Its salinity resistance makes the turf grass Pennisetum clandestinum Hochst (kikuyu grass) a candidate plant for utilization and reclamation of salinized areas. Kikuyu grass, a perennial native to the highlands of Central Africa now common in many areas, has recently become a valuable pasture and lawn plant because of its growth rate and well developed root system. However, its salt resistance has yet to be fully evaluated. The objective of this study was to identify the biochemical and physiological basis of salt resistance of kikuyu grass for the use of this grass as pasture, in phytoremediation, in controlling soil erosion and in biomass production for energy, in salt affected lands, where the growth of other species is markedly reduced. This study focused on the effect of salinity on germination, growth, metabolism, biochemistry, nutritive properties and root morphology of kikuyu grass. We compile evidence that kikuyu grass can germinate and grow in salinized areas. The use of this salt-tolerant grass may be an important part of a range of practices, such as recycling saline wastewater and reclaiming salt-affected soil in arid-zone irrigation districts.

► Kikuyu grass germination is more resistant to salinity than vegetative growth. ► Kikuyu grass displays a moderate tolerance to NaCl (50% reduction in shoot dry weight, leaf surface area and leaf number caused by 150 mM NaCl). ► The effects of salinity on germination and vegetative growth depend mainly on the culture medium. ► Kikuyu grass may be successfully used as an economically viable turf and fodder crop for salinized arid and semiarid area. ► Kikuyu is a valuable turf grass to be used as a source of biomass for bioenergy, for its high content of lignocellulotic compounds.