醉马草对几种植物种子萌发化感作用的研究

发布时间：2018-12-26 10:06

【摘要】：植物化感作用是化学生态学研究的活跃领域之一。醉马草(Achnatherum inebrians)是禾本科(Gramineae)芨芨草属(Achnatherum)多年生草本植物,是中国北方的主要毒草,严重威胁着天然草地的生态和生产安全。本研究从醉马草株体和根际土壤水浸液对6种植物种子萌发的影响出发,揭示其化感作用规律,为醉马草防控提供理论依据。主要研究结果如下:1、不同浓度醉马草水浸液处理6种植物种子后,基本表现为低浓度促进,高浓度抑制,且浓度越大,对受体植物种子萌发抑制作用越明显;不同部位的水浸液化感作用抑制强度表现为叶茎根;水浸液对受体植物种子萌发的影响在物种间和指标间存在一定的差异,综合化感效应总体表现为抑制性。2、不同时期、部位和土层的醉马草水浸液对补播牧草总体表现为抑制作用。株体水浸液的抑制程度为无芒雀麦紫花苜蓿红豆草,种子萌发期的受限程度为开花期返青期结实期,种子萌发指标的受限程度为萌发指数发芽率发芽势;土壤水浸液的受限程度为紫花苜蓿无芒雀麦红豆草,种子萌发期的受限程度为春季土壤秋季土壤裸地土壤;总体看来土壤水浸液对萌发指数和发芽势表现为促进,对发芽率为表现抑制,敏感程度为发芽率萌发指数发芽势;不同土层水浸液0-15 cm土层表现为促进作用,15-20 cm土层表现抑制作用,敏感程度从强到弱依次为15-20 cm10-15 cm5-10 cm0-5 cm;相对来说红豆草对醉马草株体和根际土壤水浸液的耐受限程度比无芒雀麦和紫花苜蓿较大;因此,在醉马草爆发区进行草地补播恢复时,应优先考虑像红豆草一样耐受性较好的优良牧草。3、不同时期、部位和土层的醉马草水浸液对伴生种总体也表现为抑制作用。株体水浸液的抑制程度为伊犁绢蒿针茅,种子萌发期的抑制程度为结实期返青期开花期,种子萌发的抑制程度为发芽势萌发指数发芽率;对土壤水浸液的受限程度为伊犁绢蒿针茅,种子萌发期的受限程度为秋季土壤裸地土壤春季土壤,平均敏感度对发芽率和发芽势表现促进,萌发指数表现抑制,种子萌发的受限程度为萌发指数发芽势发芽率,不同土层受抑制程度为0-5 cm10-15 cm5-10 cm15-20 cm;可见,醉马草株体和土壤水浸液在一定程度上影响了伴生种种子萌发和胚生长,这可能是造成其从群落中退化的原因之一。4、不同时期、部位和土层的醉马草自毒作用化感效应敏感度不同。种子萌发期的受限程度为返青期开花期结实期,种子萌发的受限程度为发芽势萌发指数发芽率;土壤水浸液对种子萌发期的受限程度为秋季土壤春季土壤裸地土壤,种子萌发的受限程度为萌发指数发芽率发芽势,不同土层受抑制程度为0-5 cm5-10 cm10-15 cm15-20 cm。但醉马草自毒作用相对较小,对很多指标表现为无影响或低浓度促进作用,加速了醉马草在群落中的繁殖蔓延。
[Abstract]:Plant allelopathy is one of the active fields in chemical ecology. (Achnatherum inebrians) is a perennial herb of (Achnatherum) genus (Achnatherum) in Gramineae. It is the main poisonous grass in the north of China. It is a serious threat to the ecological and production safety of natural grassland. In this study, the effects of water extracts on the seed germination of six species of plants were studied, and the allelopathic effects of the extracts were revealed, which provided a theoretical basis for the prevention and control. The main results were as follows: (1) after treated with different concentrations of water extract, six plant seeds were treated with low concentration, high concentration inhibition, and the higher the concentration, the more obvious inhibition effect on the seed germination of recipient plants; The inhibition intensity of the susceptibility to liquefaction in different parts was as follows: leaf stem and root; The effects of water extract on seed germination of recipient plants were different among species and indexes. The water extract of the part and soil layer inhibited the forage seeding. The inhibition degree of water extract of plant was red bean grass of alfalfa, the limited degree of seed germinating stage was green stage, and the limited degree of seed germination index was germination index germination rate. The limit degree of soil water extract was red bean grass of alfalfa without awn brome, and the restriction degree of seed germination was soil bare soil in spring and autumn. As a whole, soil water extract promoted germination index and germination potential, inhibited germination rate, and its sensitivity was germination rate germination index. In different soil layers, 0-15 cm soil layer showed promoting effect, 15-20 cm soil layer showed inhibitory effect, and the sensitivity was 15-20 cm10-15 cm5-10 cm0-5 cm; from strong to weak. The tolerance of red bean grasses to the water extracts of Rhizosphere and Rhizosphere was higher than that of bromegrass and alfalfa. Therefore, in the restoration of supplementary seeding, priority should be given to the fine forage grass, which is well tolerated as red bean grass. 3. At different stages, the water extracts of the part and soil layer also inhibit the associated species in general. The inhibition degree of plant water extract was Stipa ellii, the inhibition degree of seed germination was anthesis stage of fruiting stage, the inhibition degree of seed germination was germination potential germination index germination rate; The limiting degree of soil water extract was Stipa ellii, and the limiting degree of seed germination was autumn soil, spring soil. The average sensitivity promoted germination rate and germination potential, and the germination index was inhibited. The limited degree of seed germination is germination index germination potential germination rate, and the inhibition degree of different soil layers is 0-5 cm10-15 cm5-10 cm15-20 cm;. It can be seen that the seed germination and embryo growth of the associated species were affected to some extent by the water extracts from the plant and soil, which may be one of the reasons for its degradation from the community at different stages. The allelopathy sensitivity of the site and soil layer was different. The limited degree of seed germination period was that of returning green stage to flowering stage, and the limited degree of seed germination stage was germination potential germination index germination rate. The limiting degree of soil water extract to seed germination is autumn soil, spring soil, bare soil, germination index germination potential, and different soil layers are 0-5 cm5-10 cm10-15 cm15-20 cm.. However, the autotoxic effect of Daphnia chinensis was relatively small, and it had no effect or low concentration promoting effect on many indexes, which accelerated the propagation and spread of Elaeagnus chinensis in the community.
【学位授予单位】：新疆农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S812.6

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