PEG胁迫对不同椰枣品种耐旱生理的影响

Physiological Effects of PEG Stress on Drought Tolerance of Different Date Palm

为了评价‘Sewi’‘Helali’‘Khadrawy’3个椰枣品种的耐受干旱胁迫能力,本研究采用不同浓度的聚乙二醇(PEG)进行胁迫处理,探讨不同品种椰枣种子、椰枣幼苗在聚乙二醇胁迫下生长指标和生理指标的变化特征。结果显示:在种子萌发阶段,‘Khadrawy’在高浓度PEG胁迫下种子萌发率最高,‘Sewi’次之;在幼苗期,3个品种在受到15%PEG和25%PEG胁迫时,‘Khadrawy’鲜株重和根长均最大,其耐受渗透胁迫能力最强,叶片中生理指标脯氨酸含量较高,丙二醛含量较低,因此‘Khadrawy’在高浓度PEG胁迫下生长量大,渗透调节能力最强,‘Sewi’耐胁迫能力次之,‘Helali’较差。综上结果,‘Khadrawy’品种可能更适合干旱地区种植,比如海南的乐东、东方、三沙市和三亚等常年干旱少雨地域,盐碱化地域种植,而‘Helali’可能更适合有一定降水量但降水量较少地域种植,比如海南昌江、陵水,云南元江等。

In order to evaluate the drought stress tolerance of three date palm cultivars(‘Sewi’‘Helali’‘Khadrawy’),different concentrations of PEG were used for stress treatment to discuss the characteristics of growth index and physi-ological index changes of date palm seeds and seedlings of different varieties under PEG stress.‘Khadrawy’had the highest seed germination rate under high PEG stress,followed by‘Sewi’cultivars.At the seedling stage,when the three cultivars were subjected to 15%PEG and 25%PEG stress,the fresh plant weight and root length of‘Khadrawy’were the highest,the osmotic stress tolerance ability was the strongest,the physiological index content of proline was high,and the content of malondialdehyde(MDA)was low.Therefore,‘Khadrawy’had a large growth capacity and the strongest osmotic regulation ability under high concentration PEG stress,‘Sewi’was the second,and‘Helali’was the third.In conclusion,‘Khadrawy’may be more suitable for planting in arid regions,such as Ledong,Dongfang,Sansha and Sanya in Hainan,which are perennial arid and rainless,and salinization regions,while‘Helali’may be more suitable for planting in regions with a certain amount of precipitation but less precipitation,such as Changjiang,Lingshui in Hainan and Yuanjiang in Yunnan.