四种重金属元素对白及种子萌发的影响

Effects of Four Heavy Metals Elements on Seed Germination of Bletilla striata

以紫花白及种子为试材,去离子水作为对照,在重金属溶液中培养白及种子,研究了4种重金属(Cu、Cd、Pb、Hg)不同浓度(100、10、1、0.1、0.01 mg·L^(-1))对白及种子萌发的影响,以期探索白及种子对这4种重金属的耐受性,为重金属对兰科植物种子的萌发的研究提供参考依据。结果表明:光照下白及种子在去离子水中可以正常萌发,第10天萌发率达93%,20 d时形成叶片长为0.42 mm、原球茎直径为0.46 mm的自养性幼苗;4种重金属溶液均表现对白及种子萌发及幼苗生长的抑制作用;随着浓度的升高,抑制作用越明显;在高浓度(100 mg·L^(-1)和10 mg·L^(-1))溶液中,除Pb外,其它3种重金属中(Cu、Cd、Hg)10 d和20 d的种子的萌发率均为0%;重金属对白及种子的萌发具有延迟效应;不同的重金属对种子萌发率及原球茎直径影响略有差异;在较低浓度(0.01 mg·L^(-1))溶液中,除Cd溶液20 d形成的原球茎直径略大于CK,约为0.53 mm,其它3种重金属均小于CK。

Bletilla striata seeds were used as materials,deionized water were used as control,and the method of cultivating Bletilla striataseeds in heavy metal solutions were used to study four kinds of heavy metals(Cu,Cd,Pb,Hg)with different concentrations(100 mg·L^(-1),10 mg·L^(-1),1 mg·L^(-1),0.1 mg·L^(-1),0.01 mg·L^(-1))on the germination of the seeds of Bletilla striata.In order to explore Bletilla striata seeds to four heavy metals tolerance and provide a reference for the study of the effects of heavy metals on the germination of other orchid seeds.The results showed that the seeds of Bletilla striata could germinate normally in deionized water under light.The germination rate reached 93%on the 10th day,and the autotrophic seedlings with a leaf length of 0.42 mm and a protocorm diameter of 0.46 mm were formed at 20 days;four kinds of heavy metal solution showed the inhibition to Bletilla striata seeds germination and growth;as the concentration increased,the inhibition became more obvious.In the high concentration(100 mg·L^(-1)and 10 mg·L^(-1))solutions,except Pb,the other three heavy metals(Cu,Cd,Hg)germination rate of Bletilla striata seeds for 10 days and 20 days was 0%;heavy metals had delayed effects on the germination of Bletilla striata seeds;the effects of different heavy metals on seed growth were slightly different;in the lower concentration(0.01 mg·L^(-1))solution,the diameter of the protocorm formed in the solution except Cd for 20 days was slightly larger than CK,about 0.53 mm,and the other three heavy metals were smaller than CK.