复合增氧剂对建兰水培苗生长及生理特性的影响

Effects of polyacrylamide and urea peroxide compound oxygenator on the growth and physiological characteristics of hydroponic seedlings of Cymbidium ensifolium

【目的】研究用聚丙烯酰胺(PAM)和过氧化尿素制备复合增氧剂对建兰(Cymbidium ensifolium)水培苗生长及生理特性的影响。【方法】以直生半年建兰幼苗为试材,设5个处理,分别为CK(不加PAM和过氧化尿素,对照)、T1[不加PAM,10%(质量分数,下同)过氧化尿素]、T2(0.05%PAM,10%过氧化尿素)、T3(0.10%PAM,10%过氧化尿素)、T4(0.20%PAM,10%过氧化尿素),分析其不同时期氧气释放特性及对建兰水培苗生长、光合色素、可溶性蛋白含量、根系活力和抗氧化酶活性的影响。【结果】用PAM和过氧化尿素制备复合增氧剂,在一定时间内水体溶氧量显著增高,缓释效应增强;施用复合增氧剂处理的建兰水培苗根系鲜质量、干质量增大,叶长、叶宽和根长增加,根系活力、叶片光合色素、可溶性蛋白含量和过氧化物酶(POD)活性升高,有利于建兰的生长;在PAM含量较高时(≥0.10%),建兰水培苗成活天数显著增加,超氧化物歧化酶(SOD)活性显著提高;PAM添加量为0.10%时,建兰水培苗叶片净光合速率和根系通气组织数量最大。【结论】施用PAM和过氧化尿素制备的复合增氧剂可以提高水体溶氧量,PAM含量为0.10%时复合增氧剂能显著提高建兰水培苗的光合性能和根系活性,缓解缺氧胁迫对建兰造成的伤害,改善植株的生理特性。

【Objective】The purpose is to study the effects of compound oxygenating agent prepared with polyacrylamide(PAM)and urea peroxide on the growth and physiological characteristics of hydroponic Cymbidium ensifolium seedlings.【Method】The seedlings of C.ensifolium were used as test materials;five treatments were set:CK(without PAM and urea peroxide,control),T1[without PAM,10%(mass fraction)urea peroxide],T2[0.05%PAM,10%urea peroxide],T3(0.10%PAM,10%urea peroxide)and T4(0.20%PAM,10%urea peroxide),to analyze the oxygen release characteristics of different oxygen release agents in water and their effects on growth,photosynthetic pigment,soluble protein content,root activity and antioxidant enzyme activity of hydroponic C.ensifolium seedlings in different periods.【Result】The application of compound oxygenator prepared by PAM and urea peroxide can significantly increase dissolved oxygen in water in a certain period of time and enhance the slow-release effect.The root fresh weight and dry weight,leaf length,leaf width and root length were increased,root activity,photosynthetic pigment content,soluble protein content and POD enzyme activity were increased,which was beneficial to the growth of C.ensifolium seedlings treated with compound oxygenator.The survival days and SOD activity of the hydroponic C.ensifolium seedlings were significantly increased,under application of compound oxygenator treatments than the control when PAM content was higher(≥0.1%).The net photosynthetic rate of leaves and aerenchyma number of roots of hydroponic C.ensifolium seedlings were the highest when PAM supplemental level was 0.10%.【Conclusion】That application of compound oxygenator prepared by PAM and urea peroxide can alleviate the damage to plants and improve the photosynthetic capacity and root activity of hydroponic C.ensifolium seedlings when PAM content is 0.10%by increasing dissolved oxygen concentration in water.