Studies Of Vicia Villosa Allelopathy On Four Common Forage In The Seedling Stage

This study using germination boxes,pot experiments,and field test methods,compared the different parts of Vicia villosa and different concentrations of water extract,residue decomposing,leaf volatiles and root exudates to the effects of seed germination and growth of four kinds of forage: oat(Avena sativaL.),ryegrass(Lolium perenneL.),alfalfa(Medicago Sativa)and white clover(Trifolium repensL.),in order to understand the allelopathy of vicia villosa,evaluate allelopathic potentiality of Vicia villosa,provide the evidence of mixed broadcast,intercropping and rotation,soil improvement and quality and high vield.The main results are as follows:1.The bioassay method of germination box was used to study the different parts of vicia villosa and different concentrations of water extract to the effects of seed germination and growth of four kinds of forage.The results showed that in the range of the tested concentration,the aqueous extracts of different parts had a certain inhibitory effect on the seed germination of alfalfa and white clover,improving the seelding growth of white clover,oat and ryegrass,inhibiting the seelding growth of alfalfa.The aqueous extracts of vicia villosa reduced chlorophyll content on ryegrass,alfalfa and white clover,increased chlorophyll content on oat.The aqueous extracts promoted CAT and POD activity of white clover and inhibited CAT and POD activity of oat.The aqueous extracts promoted MDA content of oat and inhibited MDA content of ryegrass,alfalfa,white clover and the order alfalfa> ryegrass> white clover,roots> stems and leaves.2.The bioassay method of pot experiments was used to study the residue decomposing of vicia villosa to the effects of seed germination and growth of four kinds of forage.The results showed that in the range of the tested concentration,seed germination of oat and ryegrass had low concentration promotion and high concentration inhibition effect.Seelding growth ofwhite clover,alfalfa and oat had promotion effect,and the order white clover> alfalfa> oat,and seelding growth of ryegrass had inhibition effect.The residue decomposing of vicia villosa reduced chlorophyll content on oat and alfalfa,and ryegrass chlorophyll content had low concentration inhibition and high concentration promotion effect,but white clover chlorophyll content had low cocrentra tion promotion and high concentration inhibition effect.The CAT activity of oat and ryegrass had promotion effect,however POD activity had inhibition effect.The residue decomposing reduced MDA content of alfalfa and promoted MDA content of white clover.3.The bioassay method of steam distillating was used to study the leaf volatiles of vicia villosa to the effects of seed germination and growth of four kinds of forage.The results showed that in the range of the tested concentration,seed germination,seedling height and fresh weight of four forage had no effect.The leaf volatiles reduced the ryegrass and white clover dry weight and promoted oat and alfalfa dry weight,and promoted four forage chlorophyll content.The leaf volatiles promoted the CAT activity of oat,ryegrass and white clover,inhibiting the POD activity of oat and white clover,promoting the POD activity of ryegrass and alfalfa,inhibiting the SOD activity of oat and alfalfa,promoting the SOD activity of white clover,reducing MDA content of ryegrass and white clover,promoting MDA content of alfalfa.4.The bioassay method of field test was used to study the root exudates of vicia villosa to the effects of seed germination and growth of four kinds of forage.The results showed that root exudates had inhibition effect on seedling growth to four forage,and the order alfalfa> ryegrass> white clover.The root exudates inhibited enzyme activity of oat,ryegrass and alfalfa,and promoted MDA content of four forage.