Response of Gaillardia aristata Pursh to salinity

Abstract: The performance of Gaillardia aristata Pursh, irrigated with saline water was studied with the objective to identify herbaceous ornamentals for saline landscapes. Seeds were sown directly into field plots of sandy soil and irrigated with saline water at electrical conductivity (EC_W) of 2 (control), 5, 10 and 15 dSm^-1. Increase in salinity reduced the plant stand by 38% at 5 dSm^-1, 50% at 10 dSm^-1 and 67% at 15 dSm^-1, in comparison with the control. Increased salinity also decreased the mean height, number of branches and dry weight of the plants, but the differences among treatments lower than 15 dSm^-1 salinity were statistically insignificant (P>0.05). Compared with the control, the number of flowers per plant declined by 57% at 5 dSm^-1, 61% at 10 dSm^-1 and 67% at 15 dSm^-1. The differences in flower production among 5, 10 and 15 dSm^-1 treatments were not significant (P>0.05). The flower diameter was significantly reduced at 15 dSm^-1, but was not affected at the lower salinities. The results show that G. aristata could be successfully cultivated upto irrigation water salinity level 10 dSm^-1 in sandy soils.