干旱胁迫下保水剂对盘江白刺花幼苗生长和生理特性的影响

Effects of super absorbent polymers on growth and physiological characteristics of Sophora davidii vs.Panjiang seedlings under drought stress

为探究保水剂(SAP)对灌木幼苗生长和抗旱性的影响,以盘江白刺花为试验材料,在盆栽条件下,测定并分析了干旱胁迫下不同保水剂处理对白刺花幼苗生长和生理指标的变化规律。结果表明:干旱胁迫下,施用低浓度保水剂显著增加了白刺花幼苗的株高、茎粗、叶长和叶宽;3种保水剂在施用浓度低于2%时,均可显著增加白刺花幼苗叶片的可溶性蛋白、可溶性糖和脯氨酸含量,提高超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性,增强白刺花幼苗的抗旱性;主成分分析和隶属函数综合评价法分析表明,3种保水剂对白刺花幼苗的保水效果排序依次为:沃特保水剂>钾盐型保水剂>农林抗旱保水剂,且施用2%浓度的沃特保水剂可有效促进白刺花幼苗生长,减轻干旱胁迫对其幼苗的伤害,效果最佳。本研究结果为白刺花节水抗旱栽培提供了一定理论依据,可在栽培有白刺花的喀斯特山区推广使用。

In order to investigate the effect of super absorbent polymers(SAP)on the growth and drought resistance of shrub seedlings under drought stress conditions,a pot experiment to study the growth and physiological indexes of the Sophora davidii vs.Panjiang seedlings under different SAP application regimes was conducted.The results demonstrated that a low concentration of SAP increased plant height,stem diameter,leaf length and leaf width of S.davidii seedlings under drought stress.SAP applied at a concentration below 2%effectively increased the concentrations of soluble protein,soluble sugar and proline in the leaves of S.davidii seedlings,and increased the enzyme activity of superoxide dismutase,peroxidase and catalase.These findings indicate that SAP(less than 2%concentration)increases the drought resistance of S.davidii seedlings.A principal component analysis and multivariate data evaluation indicated that the water-retention effect of three tested SAP types were:Wote SAP>potassium salt-type SAP>agroforestry drought-resistance SAP.The Wote SAP(2%concentration)provided the best promotional effect on the growth of S.davidii seedlings and reduction of drought stress damage.The results of the present investigation provide a theoretical basis to enhance drought tolerance and achieve water-savings during cultivation of S.davidii,and can be readily adopted and applied in Karst mountain areas with cultivated S.davidii.