Comparison of Salt Screening Methods with Lolium multiflorum and L. perenne .

This paper will compare and report on three techniques for screening ryegrass germplasm and cultivars for tolerance to high salinity. The methods were (1) planting seed in the field in a high salinity soil and irrigating with high salinity water at Pecos, Texas (2) growing plants in sand in cone-tainers (4 cm wide and 20 cm tall) which were placed in a salt tank, where salt concentration was gradually increased over time (3) growing plants in sand in flats which were immersed every 3 to 4 days in salt water. Plants growing in the field are difficult to compare because of different maturity and plant height between L. multiflorum and L. perenne. Plants growing in cone-tainers were able to withstand much higher concentrations of salt at from 10,000 ppm (16 dS m-1) to 15,000 ppm (24 dS m-1 ) before symptoms began to occur. Plants growing in flats which were immersed showed symptoms much more rapidly and at lower salt concentrations of 5,000 ppm (8 dS m-1) compared to cone-tainers. This was likely due to salt buildup in the sand after several immersions into high salt water. The correlation coefficient between salt tolerance ratings taken on ryegrass genotypes grown in the field versus plants grown in the greenhouse was 0.60 (p > 0.001). Data will be presented showing repeatability between field trial and immersion trial.