山蚂蝗属种质芽期和苗期耐盐性鉴定和评价

Identification and Evaluation of Salt Tolerance of Desmodium Desv.atGermination Stage and Seedling Stage

为了解盐胁迫对山蚂蝗属种质生长发育的影响,本试验以6份山蚂蝗属种质为材料,对其芽期及苗期进行盐胁迫。结果表明,芽期随着盐胁迫浓度的增加,6份山蚂蝗属种质间的相对发芽率、相对发芽势、发芽指数、苗重、胚根长以及胚芽长均表现出不同程度的差异;耐盐浓度为3~9 g·L^(-1),盐极限浓度为9~12 g·L^(-1),耐盐半致死浓度为6~9 g·L^(-1),其中假地豆的耐盐浓度、盐极限浓度和耐盐半致死浓度均最大,分别为9、12、9 g·L^(-1);隶属函数综合评价结果表明,假地豆和显脉山蚂蝗的耐盐性较强;苗期随着盐浓度的增加,6份山蚂蝗属种质的质膜透性、脯氨酸含量、丙二醛含量均表现出上升趋势,叶绿素含量呈下降趋势,且种质间均存在不同程度的差异。通过隶属函数法对6份山蚂蝗属种质材料进行耐盐性综合评价,耐盐性强弱顺序为:假地豆>显脉山蚂蝗>糙伏山蚂蝗>卵叶山蚂蝗>异叶山蚂蝗>长波叶山蚂蝗。

In order to understand the effects of salt stress on the growth and development of Desmodium Desv.germplasms,6 Desmodium germplasms were used as materials to conduct salt stress at germination stage and seedling stages.The results showed that the germination rate,germination potential,germination index,seedling weight,radicle length and germ length appeared varying degrees of difference among the 6 germplasms with the increase of salt stress concentration.The salt-tolerant concentration was 3-9 g·L^(-1),while limiting salt concentration and half-lethal concentration of salt tolerance were 9-12 g·L^(-1)and 6-9 g·L^(-1),respectively.Among the germplasms,the salt-tolerant concentration,limiting salt concentration and half-lethal concentration of salt tolerance in D.heterocarpon Linn.were maximum,which were 9,12 and 9 g·L^(-1)respectively.The salinity tolerance of the tested materials was evaluated comprehensively based on the membership function,and it was considered that the salinity tolerance of D.heterocarpon and D.reticulatum Cham.were stronger than that of the tested germplasms.At the seedling stage,with the increase of salt concentration,the permeability of plasma membrane,the content of proline and malondialdehyde(MDA)of the 6 germplasms showed an rising trend,while the chlorophyll content showed a downtrend,and there were differences among germplasms in different degrees.Comprehensive evaluation of salt tolerance of 6 Desmodium germplasms was conducted by membership function,and the order of salt tolerance was as follows D.heterocarpon>D.reticulatum>D.strigillosum>D.ovalifolium>D.heterophyllum>D.sequax.