施氮肥与隔根对间作大豆农艺性状和根际微生物数量及酶活性的影响  

EFFECTS OF NITROGEN FERTILIZATION AND ROOT SEPARATION ON AGRONOMIC TRAITS OF INTERCROPPING SOYBEAN,QUANTITY OF MICRO ORGANISMS AND ACTIVITY OF ENZYMES IN SOYBEAN RHIZOSPHERE

作　　者：张向前[1] 黄国勤[2] 卞新民[1] 赵其国[3] 

机构地区：[1]南京农业大学农学院,南京210095 [2]江西农业大学生态科学研究中心,南昌330045 [3]中国科学院南京土壤研究所,南京210008

出　　处：《土壤学报》2012年第4期731-739,共9页Acta Pedologica Sinica

基　　金：国家自然科学基金重点项目(U1033004)资助

摘　　要：采用盆栽试验及种间根系分隔技术研究了施氮肥和不施氮肥两种条件下根系互作在大豆玉米间作中所发挥的优势作用。结果表明,无论在施氮肥和不施氮肥条件下相对于尼龙网分隔和完全分隔根系,未分隔处理的大豆玉米间作能增加大豆各个生育时期的叶绿素含量。施氮肥在改善大豆株高、主茎节数、有效分枝数、单株荚数和百粒重农艺性状方面的效果要大于间作,间作中根系互作只在改善大豆单株荚数和百粒重方面起到显著(p<0.05)作用。通过地下部隔根处理同样证明了大豆玉米间作由于根系的互作能提高大豆的经济产量和生物产量,但效果没有施氮肥明显。施氮肥和间作作物根系的互作不仅可以增加土壤中的细菌、真菌、放线菌和固氮菌的数量,而且可以提高脲酶、磷酸酶、转化酶和蛋白酶的活性。经相关分析得出,该试验中细菌、真菌、放线菌和固氮菌数量和脲酶、磷酸酶、转化酶和蛋白酶活性与大豆的叶绿素含量及大豆单株的经济产量和生物产量之间皆存在正相关关系,且多数之间存在显著(p<0.05)或极显著(p<0.01)正相关。本研究认为间作系统中根系的互作在改善土壤微生态环境,增加土壤微生物数量和酶活性,提高作物经济产量和生物产量方面发挥着重要作用。A pot experiment using the root separation technique was carried out to study effect of root interaction in soybean maize intercropping with or without N fertilization. Results of the experiment show that the chlorophyll content of soybean was higher in Treatment NS（ No separation） than in Treatment PS（ partially separated with nylon net） and Treatment FS（fully separated） at all the growth stages with or without N fertilization. N fertilization was better at improving agronomic traits of the soybean,such as plant height, node number of the main stem, effective branches, pods per plabt and 100-seed weight,than mere intercropping（without N fertilization） , and root interaction between the two interplanted crops played a significant（p 〈 0.05 ） role only in improving pods per plant and 100-seed weight of the soybean. The treatments of root separation underground also demonstrated that the root interaction improved economic and biological yields of the soybean,but the effect was not significant than that of N fertilization. Intereropping and N fertilization could not only increase the populations of bacteria, fungi, actinincrease and nitrogen-fixing bacteria, but also enhanced the activities of urease, phosphatase,invertase and protease. Correlation analysis revealed that the populations of bacteria, fungi,actinincrease, and nitrogen-fixing bacteria and the activities of urease, phosphatase, invertase and protease, were all significant （p 〈 0.05 ） and markedly significant（p 〈 0.01 ） related to chlorophyll content of soybean and economic and biological yields of soybean per plant. All the findings demonstrate that root interaction between interplanted crops plays an important role in improving soil micro-ecoenvironment,increasing the population of microorganisms and the activity of enzymes in the soil, and raising economic and biological yields of the crops.

关 键 词：根系分隔 间作 农艺性状 根际微生物 酶活性 

分 类 号：S154.3[农业科学—土壤学]