中文摘要：

研究了大田栽培和自然光条件下，连续两年模拟UV—B辐射（280～315nm，5．00kJ／m^2）增强对8个割手密无性系叶片丙二醛（MDA）含量的影响。UV—B辐射对割手密叶片MDA含量有显著的影响，8个割手密无性系叶片MDA含量对增强UV—B辐射存在种内差异。5个无性系叶片MDA含量有明显增加的趋势，分别为Ⅰ91—97，Ⅰ91—38，Ⅱ91—116，93—25，90—22；1个无性系MDA含量变化不明显（Ⅱ91—93），2个无性系MDA含量有降低的趋势，分别为Ⅱ91-98，92～11。UV—B辐射对割手密叶片MDA含量的影响具有年际间差异。UV—B辐射对割手密叶片MDA含量的影响存在生育期之间的差异，为伸长期〉成熟期〉分蘖期。

英文摘要：

Field studies were conducted to test the effect of enhanced ultraviolet - B （ UV - B, 280 - 315 nm, 5.0 kJ/m^2） radiation on the MDA contents of eight wild sugarcane clones under field conditions in 2003 and 2004. The UV - B radiation had significant effect on MDA contents of eight elongation of wild sugarcanes. Intraspecific responses of 8 wild sugarcane clones to enhanced UV - B radiation were observed. Increase in MDA contents of 5 wild sugarcane clones （ Ⅰ91 - 97, Ⅰ91 - 38, Ⅱ91 - 116,93 -25,90- 22） ,No change in MDA contents of Ⅱ91 -93 and decrease in MDA contents of 2 wild sugarcane clones （ Ⅱ91 -98,92- 11 ） was observed. The response difference was obvioused between 2003 and 2004. Response sensitivities of MDA contents of 8 wild sugarcane clones to UV - B radiation in different stages had the following sequence： elongation 〉 ripening 〉 tillering both in 2003 and 2004.