外源ABA对低温胁迫下越橘花期和幼果期抗寒性的影响

Effects of Exogenous ABA on Cold Resistance of Blueberry at Flowering Stage and Young Fruit Stage Under Low Temperature Stress

以半高丛越橘品种‘北陆’为试材,采用综合评价的方法,研究了在低温胁迫下不同浓度外源ABA对花期和幼果期各项抗寒性生理指标的影响,以期得到提高越橘抗寒性的最适ABA浓度。结果表明:在低温胁迫下,对越橘花蕾、花朵以及幼果喷施外源ABA,可使超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性增强,可溶性糖、可溶性蛋白质以及脯氨酸含量增加,并且随着喷施ABA浓度的增大,呈先上升后下降的趋势;外源ABA也能够降低丙二醛(MDA)含量和电解质渗出率,随着喷施ABA浓度的增大,呈先下降后上升的趋势。用隶属函数法对在低温胁迫下各抗寒性指标进行综合性评价,得出喷施浓度为20 mg·L^(-1)的外源ABA可有效缓解越橘花期和幼果期冻害,提高越橘抗寒性。

Taking half high-bush blueberry cultivar ‘Northland’ as test material, a comprehensive evaluation method was used, the effects of different concentrations exogenous ABA on various physiological indicators of cold resistance at flowering and young fruit stages under low temperature stress were studied, in order to obtain the cold resistance of blueberry the optimal concentration of ABA.The results showed that, under low temperature stress, the activities of SOD,POD and CAT were enhanced, and the contents of soluble sugar, soluble protein and proline were increased by spraying exogenous ABA on the buds, flowers and young fruits of blueberry, and they were increased first and then decreased with the increase of ABA concentration.The content of MDA and the rate of electrolyte exudation were decreased firstly and then increased with the increase of ABA concentration.According to the comprehensive evaluation of cold resistance indexes under low temperature stress by membership function method, exogenous ABA spraying concentration of 20 mg·L^(-1) could effectively alleviate freezing damage at flowering and young fruit stages and improve cold resistance of blueberry.