摘要
香蕉幼苗经水杨酸 (Salicylicacid ,SA)常温 (2 2 / 15℃ )预处理 (0 3～ 0 9mmol·L-1) 1d可显著降低 7℃低温胁迫造成的膜内电解质泄漏 ,减少 5℃低温引起的萎蔫面积 ,提高抗寒性。低浓度SA预处理 (≤ 0 1mmol·L-1)降低电解质泄漏效果不明显 ,而高浓度SA (≥ 2 5mmol·L-1)则增加了电解质泄漏 ,加剧了低温伤害。 0 5mmol·L-1SA常温处理 1d对叶绿素荧光参数 (Fv/Fm、Fv /Fm 、qP、ΦPSⅡ等 )和光合速率 (Pn)产生抑制 ,但效果未达到显著水平 ;SA预处理可明显减缓低温胁迫期间Fv/Fm、Fv /Fm 、qP、ΦPSⅡ和Pn的下降程度 ,抑制Fo及NPQ快速上升 ,加快这些参数在恢复期间 (2 2 / 15℃ )的恢复程度 ,表明SA预处理在低温胁迫期间对香蕉幼苗的细胞膜和一些光合功能提供了保护作用。
s:The possible physiological mechanism of enhancement of cold tolerance by salicylic acid (SA) in banana seedlings (Musa AAA L.cv.Williams 8188) was explored.1 d of 0.3-0.9 mmol·L -1 SA treatment at 22/15℃ (by spayed to leaves and irrigated to roots of banana seedlings) significantly enhanced chilling-resistance of banana seedlings during subsequent 7℃ or 5℃ low temperature stress,indicated by the reduction of electrolyte leakage or wilting area,respectively.Under normal growth condition (22/15℃),1 d of 0.5 mmol·L -1 treatment caused a slight decrease of Fv/Fm,Fv/Fm,qP,ΦPSⅡ and Pn.However,SA pretreatment markedly inhibited the reduction of Fv/Fm,Fv/Fm,qP,ΦPSⅡ and Pn,and alleviated the rapid increase of Fo and NPQ during 3 d of 7℃ low temperature.And during 2 d of recovery periods (22/15℃),SA pretreatment also accelerated the recovery of these photosynthetic parameters above.The results indicated that SA pretreatment could provide a protection for the cell membranes and the photosynthetic functions of the cold-stressed banana seedlings,which could help to enhance thechilling tolerance of banana plants.
出处
《园艺学报》
CAS
CSCD
北大核心
2003年第2期141-146,共6页
Acta Horticulturae Sinica
基金
广州市教委重点资助项目 (1999-11)
关键词
水杨酸
香蕉
幼苗
耐寒性
低温
电解质泄漏
光合功能
Banana
Salicylic acid
Low temperature
Electrolyte leakage
Photosynthetic functions
