Tolerance to Saline, Waterlogging, and Their Combined Stress in Kentucky Bluegrass Cultivars.

Abstract

          

High soil salinity and waterlogging, alone or co-occurring, are common problems in turfgrass management. Eight Kentucky bluegrass cultivars were exposed to four growing conditions during the seedling stage (3 weeks old) for six weeks (Study I): control (i.e. non-stress), saline (NaCl = 3 dS/m), waterlogging (pots flooded with tap water), and saline-waterlogging (pots flooded with NaCl at 3dS/m). Shoot dry weight was not affected by growing-condition, cultivar, or their interaction. A growing-condition x cultivar interaction was observed in root dry weight. Root dry weight was less affected under the control and waterlogging conditions, comparing to saline and saline-waterlogging. Little variations were observed in relative root growth in Kentucky bluegrass cultivars under each condition. As the salinity level increased to 6 dS/m in Study II, plants showed severe damage after three weeks of stress exposure. Similar to Study I, shoot growth was not influenced by either main factors or their interaction. Root dry weight was affected by cultivar, in which ‘Moonlight’ and ‘Arrowhead’ had the highest and lowest root growth, respectively.