火炬树水浸提液对波斯菊种子萌发和幼苗生长的影响

摘要

For the allelopathy mechanism of the Rhus typhina L.to Cosmos,we used the Rhus typhina L.and Cosmos bipinnata Cav.,subjected to three different part of Rhus typhina L.(leaf,root,fruit ear) aqueous extract deal the Cosmos seeds with six contents of 0.200,0.150,0.100,0.050,0.025 and 0.017 g · mL-1,as well as to water as control.We observed the changes of the indexes including the activity of superoxide (SOD),peroxidase (POD),the level of malondialdehyde (MDA) and soluble protein.With the artificial temperature decreasing,at 0.200 g · mL-1,R.typhina parts of the water extract has the greatest impact on Cosmos,the most obvious inhibition of the Cosmos' s germination rate of the seed is the aqueous extract of leaves,with the germination rate of 47％,the aqueous extract of root and grain treatment germination rate of 54％ and 72％,respectively.The root aqueous extract is the strongest promotion effect in the germination index to the Cosmos with the RI-0.483.The different of R.typhina water leaching improved both SOD activity and POD activity at 0.017-0.025 g · mL-1),whereas,signification inhibited at 0.050-0.200 g · mL-1(P＜0.05).The aqueous extract of leaf is the strongest promotion effect in the SOD activities at a concentration of 0.025 g · mL-1 with the RI 0.048,while the signification inhibited for POD activities at high concentration (0.200 g · mL-1) with the R1-0.827;with the increase of the aqueous extract concentration,the soluble protein content are decreased,the level of MDA are increased with the increase of the aqueous extract concentration,the soluble protein content was lowest with R1 of 0.585,while the level of MDA was maximum with RI of 0.475,those difference was significant with control (P＜0.05).From the allelopathic effect index,R.Typhina sensitive order from strong to weak to Cosmos was leaf,root,and fruit ear.%以火炬树(Rhus typhina L.)和波斯菊(Cosmos bipinnata Cav.)为试验材料,采用火炬树3种不同部位(叶、根、果穗)的水浸提液处理波斯菊种子,设置0.200、0.150、0.100、0.050、0.025、0.017 g·mL-1 6个质量浓度,并用清水对照,通过测定超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性、丙二醛(MDA)质量摩尔浓度、可溶性蛋白质量分数,研究火炬树叶、根和果穗不同质量浓度水浸提液对波斯菊种子萌发和幼苗生长的影响,进而探讨火炬树对波斯菊的化感抑制机理.结果表明:火炬树各部位水浸提液均在质量浓度为0.200 g·mL-1时影响最大,其中叶水浸液对种子发芽率抑制作用最明显,发芽率为47％,而根和果穗水浸提液处理下发芽率分别为54％和72％,根水浸提液对波斯菊发芽指数化感作用最强,化感效应指数(RI)值为-0.483;火炬树各部位水浸液随质量浓度升高对POD 、SOD活性的影响有双重质量浓度效应,即低质量浓度(0.017～0.025 g·mL-1)有一定促进作用,高质量浓度(0.050～0.200 g·mL-1)抑制作用显著(P＜0.05),当叶浸提液质量浓度为0.025 g·mL-1时,对SOD活性达到最大促进作用,R1值为0.048,0.200 g·mL-1对POD活性达到最大抑制作用,R1值为-0.827;可溶性蛋白质量分数随水浸液质量浓度升高而逐渐降低,MDA质量摩尔浓度随水浸液质量浓度升高逐渐增加;当叶浸提液质量浓度为0.200 g · mL-1时,可溶性蛋白质量分数最低,R1值为-0.585,MDA的质量摩尔浓度达到最大,RI值为0.475,均与对照差异显著(P＜0.05).从化感综合效应看出,火炬树各部位水浸提液对波斯菊化感作用敏感性由强到弱的顺序为叶、根、果穗.