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本文通过田间与盆栽对比试验及室内分析相结合的方法，研究了大豆连作胁迫下钼营养的变化特征。结果表明：不同连作年限播前土壤有效钼的含量低于正茬。不同生育期各连作年限土壤有效钼的变化趋势和植株钼的积累特征与正茬相似，但含量低于正茬，且在盛花期土壤有效钼降到钼营养临界值（０．１ｍｇ／ｋｇ）附近，结荚期低于临界值。结荚期连作大豆土壤和植株钼营养与根瘤固氮、植株氮营养及产量间相关显著或极显著。上述结果说明，连作胁迫导致的钼营养亏缺可能是连作大豆产量降低的一个重要原因。此外，本文还探讨了连作大豆土壤有效钼降低的原因。
In this paper, through field and pot experiments and indoor analysis, the changes of molybdenum nutrition under continuous cropping stress were studied. The results showed that the content of soil available molybdenum in different continuous cropping seasons was lower than that of continuous cropping. The trend of soil active molybdenum and the accumulation characteristics of plant molybdenum in different cropping years were similar to those in the continuous cropping, but the content was lower than those in the continuous cropping, and the available molybdenum in the full flowering period was reduced to the molybdenum nutrition critical value (0.1mg / kg) Nearby, pod stage below the critical value. During the podding stage, the relationship between molybdenum nutrition and nodule nitrogen fixation, plant nitrogen nutrition and yield were significant or extremely significant. The above results indicate that the nutrition deficit caused by continuous cropping may be an important reason for the decrease of yield of continuous cropping soybean. In addition, the paper also discussed the reasons for the reduction of available molybdenum in continuous cropping soybean.