Study On The Effect Of Container Seedling On Continuous Cropping Of Apple Sapling

The study was conducted in college of horticultural science and engineering,shandong agricultural university,national apple engineering technology research center,state key laboratory of crop biology,and wantou village,shahe town,laizhou city,shandong province,from 2018 to 2019.Test with red dew/M9-T337 as test materials,two year seedling in three kinds of specifications(10 cm×30 cm,20 cm×30 cm,30 cm×30 cm)bred in black plastic containers,in March 2019,the planting seedlings and matrix at the same time,in September2019 sampling measurement,analysis and research the container seedling raising the effect of continuous cropping obstacle to the prevention and control of apples.The results are as follows:1.Container seedling saplings are in good condition.Compared with the control(bare root seedling),the plant height,ground diameter,fresh and dry mass,and root configuration parameters(root length,root surface area,and root volume)of replanted container seedlings increased significantly,and all showed as 30cm×30cm container seedlings treated with >20cm×30cm container seedlings treated with > 10cm×30cm container seedlings.The plant height,ground diameter,fresh and dry mass,root length,root surface area and root volume of30cm×30cm container seedlings were increased by 210.28%,52.49%,189.59%,171.77%,148.53%,143.59% and 168.26%,respectively,compared with the control group of naked root seedlings.2.The activity of antioxidant enzymes in root system was increased and photosynthetic index was optimized.Compared to the treatment of container seedling root antioxidant enzyme activity and photosynthetic parameters all have different degrees of ascension,to 30cm×30 cm container seedling processing of SOD,POD and CAT activity increased by90.34%,53.92% and 60.38% respectively,the root MDA content decreased by 45.59%,the net photosynthetic rate(Pn)and stomatal conductance(Gs)increased by 114.05% and155.88%,respectively.3.The main soil enzyme activity of container seedling was increased and the content of phenolic acids was decreased.Compared with the control,the main soil enzyme activity was increased and the content of phenolic acids was decreased.The soil enzyme activity of30cm×30cm container seedlings increased the most significantly,the urease,sucrase,phosphatase and catalase activities increased by 132.83%,64.87%,63.04% and 101.97%,respectively,and the content of phlorizin,phloretin,ferulic acid,benzoic acid,vanillin and catechin decreased by 35.79%,52.25%,50.62%,41.76%,37.93% and 38.14%,respectively.4.Container seedling optimized the microbial community structure of sapling root system.Compared to the treatment of container seedling of bacteria/fungi values were significantly increased,to 30cm×30cm specification of container seedlings increase the sharpest,real-time fluorescence quantitative analysis(real-time PCR)showed that the gene copy Numbers of Fusarium oxysporum,Fusarium moniliforme,Fusarium proliferatum and Fusarium solani in 30cm×30cm container seedlings decreased by 56.42%,74.51%,93.83%and 74.63%,respectively,compared with the control;The principal component analysis(PCA)results of T-RFLP spectrum showed that the fungal community structure treated with30cm×30cm container seedlings was the furthest from the control of bare root seedlings.