轮作不同作物对苹果园连作土壤环境及平邑甜茶幼苗生理指标的影响

【目的】以25年苹果园连作土壤为对象，研究轮作不同作物对该土壤环境及平邑甜茶幼苗生理指标的影响，筛选适宜的轮作植物，为防控苹果连作障碍提供依据。【方法】取老龄苹果园土壤，混匀后填入试验沟，并在试验沟中分别种植一茬小麦（Triticum aestivum）、花生（Arachis hypogaea）、苜蓿（Medicago sativa Linn）、小葱（Allium schoenoprasum）、马铃薯（Solanum tuberosum L.）后，测定土壤有机质，速效氮、磷、钾，有效铁、锰、铜、锌含量和土壤细菌、真菌、放线菌数量变化，以及土壤酚酸类物质含量；取轮作不同作物后的土壤盆栽平邑甜茶幼苗，测定平邑甜茶幼苗生物量及根系活力、SOD、POD、CAT酶活性。【结果】与对照土壤相比，轮作小麦、小葱能够显著增加土壤有机质含量，分别增加了48.37%、36.7%；轮作马铃薯和休茬土壤有机质含量较对照降低，分别降低了8.61%、9.26%；轮作马铃薯能够显著增加土壤速效氮、磷，有效铜、铁、锌的含量，与对照相比分别增加了217.32%、240.55%、47.03%、91.38%、158.30%；轮作花生较对照能够显著降低土壤速效钾含量，但增加了有效铁、锰含量；轮作小葱、小麦、花生可增加土壤细菌总量，降低土壤中有害真菌数量，其中轮作小葱较对照细菌总量增加了200%、真菌总量下降了44.7%，轮作小麦较对照细菌总量增加了141.9%。轮作小葱、小麦使土壤细菌/真菌比值分别提高了435.8%、211.1%；轮作小葱使土壤中酚酸类物质总量较对照降低了45.3%，较轮作马铃薯降低了241.15%，较轮作小麦降低了190.07%，其中根皮苷含量较对照下降了84.2%，较轮作马铃薯下降了55.80%，较轮作小麦下降了9.30%；与对照相比，轮作小葱能显著提高平邑甜茶幼苗根系SOD、POD、CAT酶活性，分别增加了48.12%、58.33%、65.77%。从平邑甜茶生物量可以看出，轮作小葱与对照相比地上鲜重增加49.7%，地下鲜重增加76.5%，与轮作花生相比，地上鲜重显著增加了40.63%、与轮作小麦相比，地下鲜重显著增加了56.84%。【结论】轮作不同植物对连作土壤环境和平邑甜茶幼苗根系影响差异较大，轮作小葱能够增加土壤有机质含量，同时增加土壤中细菌/真菌值，降低土壤中酚酸类物质总量，提高平邑甜茶幼苗根系保护性酶活性，增加地上和地下生物量。从轮作防控苹果连作障碍角度看，轮作小葱更有利于减轻苹果连作障碍。

The Influence of Different Crops Rotation on the Environment of Soil and Physiological Characteristics of Malus hupehensis Rehd. Seedlings

【Objective】Wit the soils of 25 years continuous cropping apple orchard as the object, the influence of different crops rotation on soil environment of continuous cropping apple orchard and physiological indexes of Malus hupehensis Rehd. seedling was studied, then a preferable rotation planting crop was chosen, in order to provide a gist for the prevention and control of apple continuous cropping obstacles.【Method】 Wheat, peanut, alfalfa, shallot, and potato were planted respectively in the soil, which was collected from the old apple orchard and blended evenly, then the soil organic matter, content of available N, P, K, effective Fe , Mn, Cu and Zn, the change of the number of soil bacteria, fungi and actinomycetes, and the change of contents of soil phenolic acids were determined. At the same time, potting M. hupehensis Rehd. seedlings after rotation of different crops. The biomass and root activity, SOD, POD, and CAT enzyme activities of M. hupehensis Rehd. seedlings were determined. 【Result】The content of soil organic matter increased significantly in the crop rotation soil of wheat and shallot when compared with apple continuous cropping soil, and the increments were 48.37% and 36.7%, respectively. Soil organic matter content of potatoes crop rotation and fallowing was reduced by 8.61% and 9.26%, respectively, compared with CK, and potato rotation significantly enhanced the content of available N, P, effective Cu, Fe, and Mn, compared with controls and increased by 217.32%, 217.32%, 240.55%, 91.38% and 158.30%, respectively. Peanut rotation remarkably reduced the content of available potassium, but increased the contents of effective Mn and Fe. Simultaneously rotation with wheat, peanut and shallot increased the number of soil bacteria, inhibited the breeding harmful fungus in the soil. Among them, bacteria amounts of shallot rotation increased by 200%, fungi amount decreased by 44.7%, bacteria amounts of shallot rotation increased by 141.9%, shallot rotation and Wheat rotation enhanced the ratio of bacteria and fungi by 435.8% and 211.1%, respectively. Shallot rotation markedly reduced the content of phenolic acids in the soil by 45.3%, among them, the content of phloridzin decreased by 84.2%. Compared with potato rotation, the content of phenolic acids in shallot rotation decreased by 241.15%, and compared with wheat rotation decreased by 190.07%. Compared with CK, Shallot rotation significantly improved the root SOD, POD, and CAT enzyme activities of M. hupehensis Rehd., and increased by 48.12%, 58.33% and 65.77%, respectively. It could be seen that Shallot rotation significantly increased the ground fresh weight of M. hupehensis Rehd. by 49.7%, underground fresh weight increased by 76.5% compared with CK. Shallot rotation significantly increased the ground fresh weight of M. hupehensis Rehd. by 40.63% compared with peanut rotation, and underground fresh weight increased by 56.84% compared with wheat rotation.【Conclusion】There exist larger differences in the effect of continuous cropping soil environment and root of M. hupehensis Rehd. when rotation cropping with different plants. Shallot rotation can increase the content of soil organic matter, enhance the ratio of bacteria and fungi, reduce the content of phenolic acids in the soil, improve the root enzyme activity of M. hupehensis Rehd., and increase the ground and underground biomass. From the perspective of prevention and control of apple continuous cropping obstacles, rotation shallot is more advantageous to reduce the apple continuous cropping obstacles.