Study On Allelopathic Effect Of Medicago Varia Martin. Cv.Cao Yuan No.3

Alfalfa (Medicago varia Martin, cv. CaoYuanNo.3) is one of excellent leguminous varieties. Is the first choice of forage grass for the establishment of high quality artificial grassland. Single planting alfalfa Leading to Exacerbate of Pests and diseases.,and Decline the output. Based on the former researchs on Medicago varia Martin. cv. CaoYuanNo.3autotoxicity and Allelopathic effects of other forage, Allelopathic effects of Species and Explore Varieties Collocation problems is the key to establishment of healthy and sustainable artificial grassland.Based on research the Alfalfa (Medicag varia Martin. cv. CaoYuanNo.3)autotoxicity and the effect of germination and growth of other forage grass of seed germination process and roots、stems、leaves extract of different growth stages of Medicago varia Martin. cv. CaoYuanNo.3,and the Phenolic acids effect of germination and growth of the other forage grass. The main result of this study including:1. in a germination condition. Medicago varia Martin. cv. CaoYuanNo.3have some differences in Germination and growth period after germination of three allelopathic effects of pasture. Medicago varia Martin. cv. CaoYuan No.3the existence of three kinds of forage allelopathy in different conditions. The order of allelopathy of3pasture is that Psathyrostachys juncea>Bromus ciliatus L.>Agropyron mongolicum Keng in a living condition, The order of allelopathy of3pasture is that Bromus ciliatus L.> Psathyrostachys juncea>Agropyron mongolicum Keng.2. Comparing the allelopthic effect of aqueous extracts of aerial part and root extracts of the Medicago varia Martin. cv. CaoYuanNo.3on germination and growth of receptor plants in different growth seasons(seeding stage and blooming stage).The result showed that:In the blooming stage,the aqueous extracts of aerial part allelopthic effect than the seeding stage. The allelopthy of the aqueous extracts of aerial part was ranked in the order of Psathyrostachys juncea>Agropyron mongolicum Keng> Bromus ciliatus L. root extracts have inhibition effect of the Bromus ciliatus L.In the seeding stage,the extracts of aerial part have inhibition effect of Psathyrostachys juncea.root extract have promotion effects of the germination and growth of all the three kinds of forage.3. The different organs of Medicago varia Martin. cv. CaoYuanNo.3on allelopathic was also great differences, The allelopthy of the aqueous extracts of the different organs was ranked in the order of Leave extracts>root extracts>stem extracts.The different concentrations of Medicago varia Martin. cv. CaoYuanNo.3roots, stems, leaves extract on germination and growth of and Medicago sativa L.cv. Aergangjin、 Medicago sativa L.cv.Aohan、Bromus ciliatus L、Agropyron mongolicum Keng and to the seeds effect was different. The allelopthy of the aqueous extracts of root was ranked in the order of Agropyron mongolicum Keng> Bromus ciliatus L.> Medicago sativa L.cv. Aergangjin> Medicago varia Martin. cv. CaoYuanNo.3. The allelopthy of the aqueous extracts of stem was ranked in the order of Agropyron mongolicum Keng> Bromus ciliatus L.> Medicago sativa L.cv. Aergangjin. The allelopthy of the aqueous extracts of leaf was ranked in the order of Agropyron mongolicum Keng> Medicago varia Martin. cv. CaoYuanNo.3> Bromus ciliatus L.> Medicago sativa L.cv. Aergangjin. All of the extracts of roots, stems,leaves on Medicago sativa L.cv.Aohan have to promote the role of germination and growth.The Medicago varia Martin. cv. CaoYuanNo.3has obvious toxicity, and extracts of leaf has the most toxic. allelopathic effects(SE) of leaves、roots、stems extract are-130.54、-15.22、7.85.4. the threshold concentration of allelopathy to different forage was different.the result showed that:The allelopthy of the five kinds of threshold concentration for Bromus ciliatus L. was ranked low to high in the order of Ferulic acid、Caffeic acid、 P-hydroxybenzoic acid<P-Coumaric acid, The inhibition allelopthy of threshold concentration of Psathyrostachys juncea was ranked low to high in the order of Caffeic acid<Chlorogenic acid、P-hydroxybenzoic acid, then The promotion allelopthy of threshold concentration of Psathyrostachys juncea was ranked low to high in the order of Ferulic acid> P-Coumaric acid. The allelopthy of threshold concentration for Agropyron mongolicum Keng was P-hydroxybenzoic acid、Ferulic acid and Chlorogenic acid all have same threshold concentration, the differents concentration of Caffeic acid all promote the germianation and growth of Agropyron mongolicum Keng.