莴苣与高羊茅对蓝花楹花水浸液化感作用的响应

Responses of Lactuca sativa and Festuca arundinacea to the allelopathy of water extracts from Jacaranda mimosifolia flowers

关键词:  蓝花楹  花水浸液  莴苣  高羊茅  化感作用

Key words:   Jacaranda mimosifolia  water extracts from flowers  Lactuca sativa  Festuca arundinacea  allelopathy

摘要:

为探明蓝花楹是否存在对其它植物产生化感作用的相关物质,以生长在四川温江地区的蓝花楹完整单花为供体材料、莴苣与高羊茅为受体材料、清水处理为对照(CK),采用培养皿滤纸法进行种子萌发以及生物测定法培养幼苗,研究浓度为0.001、0.025、0.050 g·mL^-1的蓝花楹花水浸液对莴苣与高羊茅的种子萌发幼苗生长的化感作用。结果表明:莴苣与高羊茅的种子萌发均受到该水浸液的抑制作用,在萌发指数上表现较明显即综合化感效应(SE2)分别表现为-0.13、-0.27; 莴苣的苗高受到促进作用而根长和根冠比却受到抑制作用,其苗高SE3=0.13、根长SE4=-0.36、根冠比SE5=-0.16; 高羊茅的根冠比受到促进作用而苗高和根长却受到抑制作用,其SE3=-0.12、SE4=-0.08、SE5=0.16; 莴苣叶片丙二醛含量和根系活力值均受到抑制作用,其丙二醛含量的SE6=-0.25和根系活力SE7=-0.44,高羊茅的响应则相反,分别表现为SE6=0.04和SE7=0.34。当水浸液浓度为0.025 g·mL^-1时,多处出现RI极值或某种趋势的拐点,特别是受体植物的叶片丙二醛含量和根系活力值的变化。研究结果表明蓝花楹花水浸液中存在化感物质,莴苣与高羊茅对其均有不同响应,这为蓝花楹在植物景观配置及养护上提供了理论依据。

Abstract:

In order to verify whether there are relevant substances in Jacaranda mimosifolia that can produce the allelopathy to other plants. We studied the allelopathy of the concentration of 0.001,0.025,0.050 g·mL^-1 water extract of the flowers of J. mimosifolia for the seed germination and seedling growth, taking the complete single flowers of J. mimosifolia grown in Wenjiang region as materials,the seeds of Lactuca sativa and Festuca arundinacea as receptor materials, and the water treatment as the control CK. The results were as follows: firstly,the seed germination of F. arundinacea and Lactuca sativa was suppressed by the water extract,especially performance on the germination index, and the comprehensive allelopathies(SE2)were -0.13 and -0.27 respectively; secondly,the seedling height of L. sativa was promoted but its root length and root-shoot ratio were suppressed,and the values of SE3,SE₄,SE5 were 0.13,-0.36,-0.16, while the root-shoot ratio of Festuca arundinacea were promoted but its seedling height and root length were suppressed,and the values of SE3,SE4,SE5 were -0.12,-0.08,0.16 respectively. Meanwhile the MDA contents and root vigor of Lactuca sativa were also suppressed,whose values of SE6 and SE7 were -0.25 and -0.44,the values of Festuca arundinacea were 0.04 and 0.34 reversely. Most of all, when the concentration of the water extracts was 0.025 g·mL^-1, it showed the RI peak and inflection point of some trend in many places, especially the changes in MDA contents and root vigor of receiver plant's leaves. Thus, the experiment proved the existence of allelochemicals in water extract of Jacaranda mimosifolia flowers, Lactuca sativa and Festuca arundinacea,and they had different responses to the allelochemicals,which will provide the relevant theoretical basis to the plant landscape design and maintenance of Jacaranda mimosifolia in the future.