Evaluation of low-temperature tolerance of zoysia grass

摘要

Low temperature is one of the main factors limiting the growth of zoysia grasses (Zoysia spp.). This study was conducted to assess the low-temperature tolerance of zoysia grasses, and especially to explore the low-temperature tolerance of different organs. The leaf LT50 (temperature at which 50% of leaves die) of zoysia grasses tested ranged from -1.9 degrees C to -10.4 degrees C (CV 27.8%). The LT50 of different species ranked as: Z. japonica (-6.68 degrees C) < Z. sinica (-5.90 degrees C) < Z. matrella (-5.35 degrees C) < Z. tenuifolia (-3.5 degrees C) < Z. sinica var. longiflora (-3.1 degrees C) < Z. macrostachya (-2.7 degrees C). The ranges in LT50 values were Z. japonica (-1.9 degrees C to -10.4 degrees C), Z. sinica (-3.0 degrees C to -9.5 degrees C) and Z. matrella (-2.8 degrees C to -6.8 degrees C). The average LT50 values were leaf (-6.9 degrees C) > stolon (-7.8 degrees C) > rhizome (-8.4 degrees C). There was a significant correlation between LT50 values of different organs (P<0.05) suggesting that leaf LT50 could be used an indicator of low-temperature tolerance of zoysia grasses.