云南大理油棕自交子一代对低温胁迫的生理响应及抗寒性评价

低温是限制油棕生长发育和产量的重要影响因子,探究低温条件下油棕的生理响应机制,为油棕耐寒种质资源的选育及推广提供理论依据.以云南大理抗寒高产油棕成龄树的自交F1代有性系苗木为试验材料,在4℃低温胁迫下处理0(对照)、1、3、5 d,根据叶片寒害程度及其恢复生长情况将其划分为4个寒害等级,即1级(无)、2级(轻)、3级(...

Physiological Response under Low Temperature Stress and Evaluation on Cold Tolerance in Inbreding F1 Group of Oil Palm(Elaeis guineensis Jacq.) in Dali,Yunnan Pronvince

Low temperature is an important factor that restricts the growth and production of oil palm.To investigate the physiological response mechanisms of oil palm under low temperature stress would provide a theoretical basis for breeding and extension of cold resistance oil palm germplasm resources.The inbreding F1 generation seedlings of a mature oil palm tree with high-yielding and cold resistance in Dali,Yunnan Province were used as the test materials to low temperature stresses of 4℃ for 0(control),1,3,and 5 days and divided into four cold injury levels depending on the degree of leaf cold damage and the recovery of leaf growth,which were level 1(none-damaged),level 2(light-damaged),level 3(moderate-damaged),and level 4(severe-damaged).Furthermore,the content of malondialdehyde(MDA),content of proline(Pro),content of soluble sugar(SS),peroxidase(POD) activity and superoxidase dismutase(SOD) activity was determined for each cold injury level and used for the comprehensive evaluation of cold tolerance of different cold injury level oil palm materials with the membership function method.All plants of the inbreding F1 generation seedlings of mature oil palm tree with cold resistance in Dali,Yunnan Province did not have obvious cold injury symptoms during the low temperature treatment period,but gradually showed different degrees of cold injury symptoms at the recovery of leaf growth.The physiological indicators of four cold injury level oil palm leaves were significantly different among the cold levels and stress times under low temperature stresses.The content of MDA,Pro,SS and SOD activity gradually increased with the extension of low temperature stress time,while the POD activity fluctuantedly decreased.The content of MDA at lighter cold level was significantly lower than that at higher cold level(P<0.05).SOD activity at lighter cold level was significantly higher than that at higher cold level(P<0.05).Thus MDA and SOD could be used as references index for the cold resistance evaluation of oil palm.The membership function method could be used for the comprehensive evaluation on different cold tolerance materials and the result was level 1>level 2> level 3> level 4,which was consistent with the observation of the degree of leaf cold damage and the recovery of growth under low temperature stresses.It show that membership function method has certain accuracy and feasibility in cold tolerance evaluation of oil palm.