Induced Mutations for Plant Breeding·Agricultural Biotechnology
CAO Qiwei, DU Lianda, YANG Zonghui, LI Libin, DUAN Xi, YANG Wenqiang, CHEN Wei, MENG Zhaojuan
In order to clarify the different tolerance of cucumber germplasm to NaCl, the salt-tolerant material MC2065 and salt-sensitive material White cucumber were used to verify the appropriate concentration of 50, 100, 150, 200, and 250 mM NaCl. And nine physiological and biochemical indexes, including salt tolerance index, chlorophyll, and protective enzymes under NaCl treatment were used to evaluate the salt-tolerances of 21 germplasms. The results showed that 100 and 150 mM could be the appropriate concentration.The salt injury index of White cucumber was 35.94% in 100 mM NaCl, showing obvious damage to leaves, while that of MC2065 was 4.69% and showed no obvious damage. Under 150 mM, both showed obvious damage, more than half of leaves were withered for White cucumber, but less than half for MC2065. With cluster analysis, 21 germplasms were divided into 3 groups. The first group categorized as salt-tolerant germplasm, including ZQ3, N26-5-1, Shoushui 1, DRTJY-2, Laixi, Cuiyu, 20S077-1. The second group, including DJ04, DY-1, XY1, YY9123, M2XT, D1503, X805, was medium salt-tolerant germplasm. And the third group was salt-sensitive germplasm, which included F6-3-1, SJ11-1, XB23, 20S091-1, HLT-921h, AZ-1, DRT345. The trend of comprehensive scores of cucumber germplasm by the compoment analysis was basically consistent with that obtained by cluster analysis and seedlings survival rate. The study will provide references for investigating cucumber salt-tolerant mechanism and lay a foundation for the breeding of cucumber salt-tolerant varieties.