Effects Of Matrine On Soil Microorganism Of Apple Replant Condition And The Malus Hupehensis Rehd. Seedlings

The experiment was carried out at the National Apple Engineering Center Experimental Station of Shan Dong Agricultural University and Apple Replanting and Microbiology Laboratory from 2017 to 2019.The seedlings of Malus hupehensis Rehd.were used as test materials in pot experiment.The effects of Matrine on the growth of Malus hupehensis Rehd seedlings and soil microbial environment were studied,and the possibility of using matrine to alleviate the apple replant disease（ARD）was clarified.The main results were as follows:1.After different amounts of matrine treatment,both the number of bacteria and fungi in soil decreased but with the more decreased number of fungi than that of bacterial and the resultant increased ratio of bacterial to fungi.After adding 0.1‰matrine in replanted soil,the number of bacteria and fungi decreased by 58.5%and 68.2%respectively compared with the control.2.The diversity of fungi in soil was analyzed by terminal restriction fragment length polymorphism（T-RFLP）.With the increase of matrine dosage,diversity index and richness index decreased,dominance index increased,and evenness index had no obvious changes.The diversity index and richness index of 0.1‰matrine decreased by 11.6%and 10.2%compared with the control,and the dominance index increased by 21.4%.The absolute Fusarium oxysporum,Fusarium proliferatum,Fusarium moniliforme,Fusarium oxysporum numbers by a real-time quantitative PCR detection system showed that the variation of gene copy number of the four fungi was consistent with that of fungi.The highest number of gene copies of the four strains is the control.With the increase of matrine dosage,the number of gene copies decreases.0.1‰matrine treatment,Compared with the control group,the number of gene copies of Fusarium oxysporum,Fusarium proliferatum,Fusarium moniliforme and Fusarium oxysporum were reduced by 51.2%,43.3%,39.9%and 44.5%,respectively.3.After the application of matrine,Take the September data as an example for analysis.Compared with continuous cropping,0.1‰matrine could significantly improve plant height,ground diameter and dry quality of Malus hupehensis Rehd seedlings.These increases were51.9%,63%and 57.1%,respectively.The addition of 0.05‰matrine could also increase the plant height,ground diameter and dry weight of seedlings,but the promotion was not obvious.The addition of 1‰of matrine significantly inhibited the growth of seedlings under replanted soil.4.Both 0.05‰and 0.1‰matrine treatments could improve the root index of seedlings.Root length,root area,root volume and root respiration rate of seedlings treated with 0.1‰matrine were improved by 22.4%,17.1%,29.9%and 23.1%,respectively.In addition,the net photosynthetic rate,transpiration rate and stomatal conductance of leaves treated with 0.1‰matrine were 15.5%,41.3%and 29.3%higher than the control,respectively.There was no significant difference in intercellular CO₂ concentration.5.At different matrine level,the SOD activity of the root system of Malus hupehensis Rehd seedlings varied.Among them,the SOD activity was the highest in the treatment with0.1‰matrine,followed by 0.05‰.The activity changes of POD and CAT were consistent with the trend of SOD activity.The activity of SOD,POD and CAT were 1.78,2.09 and 1.76times of the control.Compared with the control,Both 0.05‰and 0.1‰matrine treatments could significantly reduce the content of MDA in seedlings roots,which was 23.1%and39.2%,respectively.The MDA content of roots treated with 1‰matrine increased.