镍胁迫对薏苡种子萌发及幼苗生理特性的影响OA

To investigate the effects of nickel(Ni)stress on seed germination and seedling physiological characteristics of Coix lacryma-jobi,the cultivar Puyi No.6 was used as the test material.8 Ni concentration treatments were set,namely 0(CK),2.5,5,10,15,20,25,and 30 mg/L.For each treatment,seed germination rate,germination energy,germination index,seedling root length,shoot length,malondialdehyde content,and catalase activity were measured.The results showed that at the Ni concentration of 5 mg/L,the germination rate and germination energy reached 94.67%and 94.00%,respectively,which were slightly higher than those of the CK.When the Ni concentration reached≥10 mg/L,the germination energy and germination rate of Coix lacryma-jobi seeds showed an overall declining trend with increasing concentration.Compared with the CK,the root length,shoot length,vigor index,shoot fresh weight,shoot dry weight,root fresh weight,and root dry weight of Coix lacryma-jobi under Ni stress were all lower than those of the CK.At Ni concentrations ranging from 5 to 20 mg/L,compared with the CK,the chlorophyll content increased,the electrical conductivity decreased,the catalase activity increased,while the superoxide dismutase activity decreased.These results indicate that Ni stress has an obvious inhibitory effect on the growth of Coix lacryma-jobi,but stress within a certain concentration range(5-20 mg/L)can stimulate the plant to activate its own defense system,thereby enhancing its adaptability.This study provides a reference for the breeding of Ni-tolerant Coix lacryma-jobi varieties.