Inhibition Of Peach Orchard Soil On The Growth Of Malus Hupehensis Seedlings And Ameliorating Effects Of Mineral Chameleon

The experiment was carried out in the National Apple Experiment Center of Shandong Agricultural University from March 2015 to May 2017.In order to explore the effects of the peach orchard soil on the biomass,roots and photosynthetic parameters of Malus hupehensis Rehd.seedlings and ameliorating effects of mineral chameleon,potted apple seedlings were studied.The main results were as follows:1.The harmful microorganisms from peach orchard soil inhibited the growth of Malus hupehensis Rehd.seedlings.And plant biomass,root respiration rate,SOD,POD and CAT activities was reduced too.In July,August and September,the number of fungi in peach orchard soil treatment increased significantly,and the ratio of bacteria and fungi was significantly lower than that of other treatments,the soil was changed to fungal soil.Compared with the methyl bromide fumigation control,the plant height was decreased by 41.35%,30.68%,24.15%,and plant ground diameter was decreased by 46.32%,28.11%,24.26%,fresh weight decreased by 40.08%,31.50%,30.90%,dry weight was reduced by 30.92%,39.21%,35.97% too.The Malus hupehensis Rehd.seedling roots were significantly stressed by harmful microorganisms.Root respiration rate were significantly decreased by 50.40%,53.59%,47.18%.SOD activity was significantly decreased by 28.85%,33.56%,27.36%,POD activity was decreased by 69.28%,63.83%,56.41%,CAT activity was significantly decreased by 33.96%,44.78%,39.01%.In addition,photosynthesis of seedlings in peach orchard treatment was also significantly inhibited,the net photosynthetic rate(Pn)was significantly reduced by 51.32%.2.The amygdalin and benzoic acid from peach orchard inhibited the growth of Malus hupehensis Rehd.seedlings,reduced the root respiration rate and root activity of protective enzymes and photosynthesis.In July,compared to fallow soil,the seedling plant height,ground diameter,fresh weight,dry weight of amygdalin treatment decreased by 27.43%,28.85%,50.92%,46.90%,and those of benzoic acid treatment were also significantly 41.28%,44.01%,71.57%,70.08% lower,and showed the same trend in August and September.Seedling root respiration and root protective enzyme activity were significantly inhibited of amygdalin treatment and benzoic acid treatment.In July,compared to fallow soil,the root’s respiration rate and SOD,POD,CAT activity were significantly decreased by 46.99%,62.23%,50.37%,62.96% of amygdalin treatment,and those of benzoic acid treatmentsignificantly decreased by 49.67%,46.78%,40.26%,71.28%.In addition,Pn of amygdalin and benzoic acid treatments were significantly decreased by 30.95%,36.97% than fallow soil.And the same as July in August and September.3.The mineral chameleon could effectively alleviate the stress effect of peach orchard soil on Malus hupehensis Rehd.seedlings,and significantly increase the seedling biomass,root respiration rate and activity of protective enzymes.In July,compared with the peach orchard soil treatment,the plant height,ground diameter,fresh weight and dry weight were significantly increased by 56.67%,52.28%,192.96%,197.70%.And root length,root surface area,root volume were significantly increased by 149.01%,255.79%,415.20%.And showed a significant increase trend in August.The root respiration rate significantly increased by49.42%;the SOD,POD,CAT activity were significantly increased 73.79%,73.44%,101%.In addition the content of MDA in root was significantly decreased by 59.53%.