Irrigation Water Salinity Effects Germination, Emergence and Growth of Halophytes.

Low availability of surface water has exacerbated the use of groundwater for irrigation in New Mexico. 75% of the groundwater is saline and could increase soil salinity with prolonged application without treatment. Reverse Osmosis (RO) could treat saline groundwater but environmentally safe disposal of RO concentrate is a problem. The objective of this study was to test the germination, emergence, and growth of halophytes under a salinity gradient. Four irrigation water treatments used include irrigation with tap water (EC 0.8 dS/m), well water (EC 4.0 dS/m), RO concentrate water (EC 8.0 dS/m), and RO concentrate mixed with NACI (10 dS/m). All experiments with six halophytes species (Atriplex canescens, Hordeum vulgare, Lepidium alyssoides, Distichlisstricta, Panicum virgatum, ×Triticosecale) were carried out for 30 days in a greenhouse. The germination experiments were carried out in 90 mm-diameter petri-dishes using #3 Whatman blotting filter paper. For emergence experiments, 96 columns were packed with sandy loam soil. Mean germination time, mean emergence time, germination index, emergence index, Timson’s index and Timson’s modified index for germination and emergence were obtained for replicated experiments. Results of the final germinability percentage showed that H. vulgare and xTriticosecale had no significant difference with higher germinations under salinity treatments. The L. alyssoides seeds showed higher germinations under higher salinity treatments. On the other hand, D. stricta seeds displayed lower germination under higher salinity treatments. Results of final emergence percentage showed that H. vulgare and xTriticosecale had no significant difference with higher emergence under higher salinity treatments. In contrast, L. alyssoides and D. stricta seeds showed lower emergence percentage under higher salinity treatments. Analysis of growth data are in progress and results will be included in the presentation.