玉米连作农艺性状与土壤理化性质及酶的相关性分析

Correlation analysis of maize continuous cropping agronomic characters with soil physicochemical properties and enzymes

【目的】分析不同连作年限下玉米根际土壤和玉米生长发育的相互关系,探明连作对玉米生长发育和根际土壤理化性质及酶活的影响。【方法】在甘肃省张掖市甘州区沙井镇兴隆村分别测量轮作1年、连作5、11、25和50年的玉米农艺性状和根际土壤理化性质及酶活,运用SPSS 22.0软件对试验数据进行方差分析。【结果】水解性氮随连作年限延长,先下降后上升,有效磷、速效钾和pH随连作年限延长,呈先上升后下降趋势;玉米不同连作年限下根际土壤的土壤蔗糖酶(S-SC)、土壤脲酶(S-UE)、土壤碱性磷酸酶(S-AKP/ALP)和土壤过氧化氢酶(S-CAT)含量差异显著,都随着连作年限的延长呈先上升后降低趋势。连作对玉米生物学特性的影响差异显著,其中轮作1年的玉米长势相对较均匀,叶绿素含量高,连作11年的玉米光合作用最强,根系发育好,毛根长,在主根上分布均匀;土壤速效磷、速效钾和弱碱性土壤以及土壤碱性磷酸酶、土壤蔗糖酶可以促进玉米根系发育。【结论】连作导致玉米农艺性状下降,土壤中有效磷、速效钾流失,水解性氮富集,土壤酸化。土壤速效磷、速效钾和弱碱性土壤以及土壤碱性磷酸酶、土壤蔗糖酶可以促进玉米根系发育,水解性氮、土壤脲酶和土壤过氧化氢酶(S-CAT)含量升高不利于玉米根系发育。

【Objective】The present paper aimed to analyze the relationship between maize rhizosphere soil and maize growth and development under different continuous cropping years,and discussed the effects of continuous cropping on the growth and development of maize and the physicochemical properties and enzyme activities of rhizosphere soil.【Method】The agronomic characters of maize,the physicochemical prop⁃erties of rhizosphere soil and the enzyme activities of maize were measured in Xinglong village,Shajing town,Ganzhou district,Zhangye cit⁃y,Gansu province,respectively for 1,5,11,25 and 50 years of continuous cropping.The variance analysis of the experimental data was carried out using SPSS 22.0 software.【Result】Hydrolyzable nitrogen decreased first and then increased with the extension of continuous cropping years,and available phosphorus,available potassium and pH increased first and then decreased with the extension of continuous cropping years;The activities of S⁃SC,S⁃UE,S⁃AKP/ALP and S⁃CAT in the rhizosphere soil of maize under different continuous cropping years were significantly different,all of which increased first and then decreased with the extension of continuous cropping years;The effects of continuous cropping on the aboveground biological characteristics of maize were significantly different.Among them,the growth of maize in rotation for one year was relatively uniform,and the chlorophyll content was high.The photosynthesis of maize in continuous cropping for 11 years was the strongest,the root system was well developed,the hairy root was long,and the distribution was uniform on the main root;Soil available phosphorus,available potassium,weak alkaline soil,S⁃AKP/ALP and S⁃SC could promote the root development of maize.【Con⁃clusion】Continuous cropping leads to the decline of corn agronomic traits,the loss of available phosphorus and available potassium in the soil,the enrichment of hydrolytic nitrogen,and the acidification of the soil.Soil available phosphorus,available potassium,weak alkaline soil,S⁃AKP/ALP and S⁃SC can promote the development of maize roots.The increase of hydrolytic nitrogen,soil urease(S⁃UE)and soil catalase(S⁃CAT)was not conducive to maize root development.