Monday, November 13, 2006

Seed and Seedling Salinity Tolerance of South Texas Native Plants.

LeeRoy Rock1, Shad Nelson1, and John L. Reilley2. (1) Texas A&M Univ, Kingsville, 700 Univ Blvd Apt. #9A, Kingsville, TX 78363, (2) USDA-NRCS Plant Materials Center, 3409 North FM 1355, Kingsville, TX 78363

An estimated 600 thousand acres of South Texas land is affected by alkaline and saline soil conditions. Natural weathering of rocks and minerals contribute to soil salinity, but a major cause of this has been attributed to past oil and natural gas excavation. Onsite disposal of drilling fluids and spills introduce high amounts of salts onto the soil surface. Typically, high amounts of soluble salts prevent the establishment of plants native to South Texas. To reintroduce these plants onto saline and alkaline sites both seed germination and young seedling response to varying salinity levels requires further investigation. This study focused on 21 native species response to saline conditions in seed germination chambers and a controlled greenhouse. Seed germination salinity trials in NaCl were run at an EC of 0, 5, 10, 20, 30 dS m-1 at 20 and 30C . Seedling stand salinity tolerance was run at 0, 15, and 30 dS m-1. Results showed that for some native species a positive relationship between increased salinity tolerance and temperature. Several native species demonstrated tolerance to high levels of salt that may prove useful for the revegetation and restoration of salt-affected lands.



Handout (.pdf format, 138.0 kb)