外源芸苔素内酯对甘蔗抗旱性的影响

Effects of Exogenous Brassinolide on Drought Resistance of Sugarcane

以甘蔗品种‘ROC22’(‘新台糖22号’)为研究对象,采用桶内种植的方式进行培育,当甘蔗幼苗长出5~7片真叶时进行处理,共设置4个处理,即正常供水(CK)、水分胁迫(WS)、正常供水+0.04mg/kg芸苔素内酯(ER)、水分胁迫+0.04mg/kg芸苔素内酯(WS+ER)。对水分胁迫下外源芸苔素内酯与甘蔗幼苗鲜重、抗氧化酶活性、MDA(丙二醛)含量、叶片含水量及叶绿素荧光参数等生理指标的关系进行研究,探讨外源激素芸苔素内酯对甘蔗抗旱性的影响。结果表明,在水分胁迫的条件下,对甘蔗幼苗喷施适宜浓度的外源芸苔素内酯,可以显著提高甘蔗幼苗的鲜重、抗氧化酶活性、叶片含水量,使MDA含量降低,叶片的叶绿素荧光参数有所增加,即叶绿素含量增加、活性提高,从而提高甘蔗幼苗的抗旱性。通过验证外源芸苔素内酯对甘蔗的抗旱诱导作用,为今后甘蔗抗旱生产实践提供参考。

In this experiment,the sugarcane variety'ROC22'('Xintaitang 22')was selected as the research object,and was cultivated in the way of bucket planting.When the sugarcane seedlings grew 5-7 true leaves,the treatments were applied to them.And a total of four treatments were set up,those were,normal water supply(CK),water stress(WS),normal water supply+0.04 mg/kg brassinolide(ER),water stress+0.04 mg/kg brassinolide(WS+ER).The relationships between exogenous brassinolide and physiological indexes such as fresh weight of sugarcane seedlings,activity of antioxidant enzymes,content of malondialdehyde(MDA),water content of leaves and chlorophyll fluorescence parameters under water stress were studied to explore the effects of exogenous hormone brassinolide on drought resistance of sugarcane.The results of this study showed that under the condition of water stress,applying exogenous brassinolide with appropriate concentration to sugarcane seedlings could significantly increase the fresh weight,antioxidant enzyme activity and leaf water content of sugarcane seedlings,reduce the content of MDA,and increase the chlorophyll fluorescence parameters of leaves applying exogonons brassinolide with a ppropriate concentration could.In other words,the increase of the chlorophyll content and activity would improve the drought resistance of sugarcane seedlings.By verifying the drought-resistant induction effect of exogenous brassinolide on sugarcane,it could provide a reference for the drought-resistant production practice of sugarcane in the future.