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在澳大利亚实地观测了木麻黄根瘤与22种寄主和土壤化学性质的关系。在调查的5种木麻黄中,发现4种具有完整的根瘤。有效磷含量高的土壤,木麻黄属(Casuarina)根瘤比异木麻黄属(Allocasuarina)出现频度大,后者有8个种在任何土壤上都无根瘤存在。而在有根瘤的9种异木麻黄属树种植株上,根瘤的数量也很少。土壤化学性质(除有效磷水平外)与根瘤无显著关系。在温室条件下,用生长有木麻黄苗的野外土壤接种时,其结果与野外观测相似。异木麻黄属树种形成外生菌根比木麻黄属树种普遍。两个属树种都形成囊枝状菌根。第二个温室试验说明低磷和侵染性放线菌(弗兰克氏菌属缺乏是某些野外土壤中根瘤缺乏的两个因子。本文考虑了限制植物生长的其他土壤性质对木麻黄根瘤的影响,并且讨论了木麻黄科植物固氮的潜在意义。在田野木麻黄(A.campestris)、笛尔斯木麻黄(A.dielsia-na)及洛赫尔木麻黄(A.lehmanniana)上发现的根瘤,前人都未做过记录。
The relationship between the root nodules of Casuarina equisetifolia and the chemical properties of 22 hosts and soils was observed in the field in Australia. Among the five species of Casuarina found in the survey, four species were found to have complete nodules. In soils with high availability of phosphorus, the occurrence of Casuarina nodules was more frequent than that of Allocasuarina, and the latter eight species did not exist in any soil. However, the number of nodules on the 9 species of heterotrichum species with nodules is very small. Soil chemical properties (except for available phosphorus levels) and nodules no significant relationship. Inoculation of field soil with Casuarina equisetifolia seedlings under greenhouse conditions showed similar results to field observations. Erianthus species formation ectomycorrhizal than Casuarina common species. Two genera form cyst mycelia. The second greenhouse experiment showed that both low-P and invasive actinomycetes (lack of Frankenstrus is the nodule-deficient factor in some soils in the field.) This article considers the effects of other soil-limiting plant growth effects on nodules , And discussed the potential significance of nitrogen fixation in Casuarina plants. The nodules found in the fields A. campestris, A. dielsia-na and A. lehmanniana , No record has been made before.