喷施黄腐酸对干旱胁迫下甘蔗苗期叶绿素荧光参数及丙二醛的影响

Effects of fulvic acid on chlorophyll fluorescence parameters and MDA of sugarcane seedling under water stress

关键词:  甘蔗  黄腐酸(FA)  水分胁迫  叶绿素荧光

Key words:  sugarcane  fulvic acid  water stress  chlorophyll fluorescence

摘要:

分别对具4～5张完全叶桶栽甘蔗品种ROC22#和园林6#叶面喷施黄腐酸,分别为正常供水0(CK1)、0(CK2)、200、400、800、1 200 mg/L黄腐酸,研究在不同胁迫程度下不同浓度黄腐酸对甘蔗叶片叶绿素荧光参数、丙二醛(MDA)含量变化的影响。结果表明,经过黄腐酸处理后甘蔗叶片的PSII原初光能转换效率(Fv/Fm)、光合量子产额(Yield)、光化学淬灭系数(qP)数值在中度和重度水分胁迫下都高于干旱对照CK2,品种和处理间参数的变化有差异; 非光化学淬灭系数(qN)值则与正常供水对照比较没有大的差异。黄腐酸处理后甘蔗叶片MDA含量随处理浓度增大而降低,且明显低于干旱对照CK2。从2个参试品种6个处理浓度综合分析,水分胁迫下喷施黄腐酸可提高ROC22#和园林6#甘蔗苗期的抗旱性,以200、400 mg/L处理效果较好。

Abstract:

Two sugarcane cultivars,i.e. ROC22# and YUANLIN6#,were used as the plant materials for the experiment. Normal water supply(CK1)and fulvic acid(FA)of five concentration levels,i.e.0 mg/L(water,CK2),200 mg/L,400 mg/L,800 mg/L and 1 200 mg/L were sprayed on the leaves at initial growth stage(four to five leaves)to study the effects of different FA treatments on chlorophyII fluorescence parameters and MDA in sugarcane seedlings under different degree water stress. The results showed that Fv/Fm,Yield and qP was higher in FA treatments than those of control-2 under moderate water stress and severe water stress. Differences in parameters of varieties and among treatments were found. Comparing with the CK1,the difference of qN among treatments is not obvious. The higher the FA concentration treatments were,the lower the content of MDA was. The content of MDA was significantly lower in FA treatments than that of control-2. On the whole,spraying FA can improve drought resistance at initial growth stage in ROC22# and YUANLIN6# under water stress. The effects of 200 mg/L and 400 mg/L FA concentration treatments were better than those of other FA concentration treatments.