[Effects of residual apple fermentation products on continuous cropping soil environment and the growth of Malus hupehensis Rehd. Seedlings]

Effects of fermented apple products on the growth of continuous cropping Malus hupehensis Rehd. seedlings and soil environment were examined in a pot experiment to provide theoretical basis for apple replant disease. There were four treatments, the replanted soil (control, CK), sterilized replant soil (T₁), replanted soil applied with apple fermentation products (T₂), and replanted soil applied with sterilized apple fermentation products (T₃). The results showed that T₁, T₂ and T₃ significantly promoted seedlings growth, with better performance of T₁ and T₂. T₁ increased root respiration rate, plant height, ground diameter, fresh weight, and dry weight by 107.3%, 50.6%, 42.4%, 171.7%, 225.3%, while T₃ increased them by 104.4%, 50.6%, 42.3%, 171.8%, 225.5%, respectively over CK. T₂ and T₃ increased the activities of nutrient conversion-related enzymes in continuous cropping soil. T₂ increased the activities of catalase, urease, neutral phosphatase and sucrase by 44.5%, 169.5%, 23.4%, 169.3%, while T₃ increased them by 23.7%, 72.6%, 1.5%, 121.5%, respectively. Catalase and sucrase activities under T₁ treatment did not differ from that in CK, whereas their urease and neutral phosphatase activities were reduced by 40.8% and 41.6%, respectively. The contents of ammonium, nitrate, available phosphorus and available potassium in T₂ soil were increased by 18.6%, 50.6%, 14.0% and 36.7% respectively. T₃ only increased the content of available nitrogen, with ammonium and nitrate being increased by 7.0% and 23.6% respectively. The content of available nutrients of T₁ decreased compared with CK. T₁ and T₂ significantly reduced the abundance of actinomycetes and fungi in soil and increased that of bacteria. The abundance of bacteria, actinomycetes and fungi in T₃ treatment were all significantly decreased. Results of real-time fluorescence quantitative PCR analysis showed that the gene copies of Fusarium proliferaturn, F. moniliforme, F. solani and F. oxysporum in T₁, T₂ and T₃ were ecreased to different degrees. Apple fermented product could inhibit soil pathogen in replanted orchard soil, improve soil environment, and promote seedling growth, which could be used to alleviate the apple replant disease.

在盆栽条件下,研究残次苹果发酵产物对连作土壤环境及平邑甜茶幼苗生长的影响,为减轻苹果连作障碍提供理论依据。试验以连作土壤为对照(CK),设置溴甲烷灭菌连作土壤(T₁)、连作土壤施加苹果发酵产物(T₂)、连作土壤施加灭菌苹果发酵产物(T₃)处理,测定了土壤和平邑甜茶幼苗的相关指标。结果表明: T₁、T₂、T₃能显著促进平邑甜茶幼苗的生长,其中以T₁和T₂的效果较好,其根系呼吸速率、株高、地径、鲜质量、干质量分别比CK提高了107.3%、50.6%、42.4%、171.7%、225.3%和104.4%、50.6%、42.3%、171.8%、225.5%。T₂和T₃提高了连作土壤中养分转化相关酶的活性,过氧化氢酶、脲酶、中性磷酸酶和蔗糖酶活性分别比CK提高了44.5%、169.5%、23.4%、169.3%和23.7%、72.6%、1.5%、121.5%;T₁处理的过氧化氢酶和蔗糖酶活性与CK无显著差异,脲酶和中性磷酸酶活性分别降低了40.8%和41.6%。T₂土壤铵态氮、硝态氮、速效磷和速效钾含量分别较CK提高了18.6%、50.6%、14.0%和36.7%;T₃只提高了速效氮的含量,铵态氮和硝态氮含量分别提高了7.0%和23.6%;T₁与CK相比速效养分含量有所降低。T₁和T₂显著降低了土壤放线菌和真菌数量,增加了细菌数量;T₃处理的细菌、放线菌和真菌数量均较CK显著降低。实时荧光定量PCR分析发现,T₁、T₂和T₃处理的层出镰孢菌、串珠镰孢菌、腐皮镰孢菌和尖孢镰孢菌基因拷贝数均较CK有不同程度的降低。表明苹果发酵产物处理能抑制连作土壤病原菌,改善土壤环境,促进平邑甜茶幼苗生长,可作为一种减轻苹果连作障碍的方法。.

Keywords: apple replant disease; residual apple fermentation product; soil microorganism; soil nutrient.