Effect of salinity on the growth of chicory (Cichorium intybus cv. Puna) — a potential dairy forage species for irrigation areas

Abstract

Chicory (Cichorium intybus L.) cv. Puna, a potentially useful forage species for dairy cows is reported anecdotally to have moderate salt tolerance and its tolerance to saline conditions was evaluated in a greenhouse experiment at Tatura, Victoria. Plants were grown hydroponically at 5 salinity levels (0, 50, 100, 150 and 200�mmol/L NaCl) along with plants of 4 other broadleafed species, lucerne (Medicago sativa) cvv. Salado and L52, white clover (Trifolium repens) cv. Victorian Irrigation and strawberry clover (Trifolium fragiferum) cv. Palestine.Plant survival rates were high for all species at all salinity levels but all plants species showed symptoms of being salt-affected, and had slower and more stunted growth at the higher salinity levels. Chicory produced significantly (P<0.05) more plant dry matter over the range of salinity levels compared with the other 4 species. Both the lucerne cultivars produced more (P<0.05) dry matter than strawberry and white clover and cv. Salado produced significantly (P<0.05) more dry matter than the other lucerne cultivar, L52. No differences were apparent between the 2 clover species, and these species were clearly the lowest yielding in terms of dry matter production. In relative terms (yield in saline conditions as compared with that in non-saline conditions), there were no significant differences between any of the 4 plant species. Dry matter digestibility levels increased in all species with increasing external salinity levels and ranged from 70 to 88%.These results suggest that chicory has a degree of salt tolerance that is similar to lucerne and therefore could be an alternative dairy forage species in moderately saline areas and on farms that use pumped saline groundwater for irrigation. However, further assessments of its salt tolerance under field conditions are recommended.