籽粒苋不同富钾基因型根际钾营养与根系特性研究

Nutrition of Potassium in Rhizosphere and Characteristics of Roots in Different Grain Amaranth Genotypes

在缺钾土培和水培条件下,研究了籽粒苋不同基因型根际和非根际土壤速效钾、缓效钾和全钾含量的变化,以及根际微生物数量、根系主要分泌物、根系质子分泌量和根系CEC的变化。结果表明,籽粒苋根际土壤速效钾和缓效钾含量明显高于非根际土壤,且在根际形成钾的相对富集区,富钾基因型R104和K12根际钾的富集能力明显高于一般基因型;籽粒苋根际土壤的全钾含量却低于非根际土壤,富钾基因型的降低幅度大于一般基因型。富钾基因型根际微生物数量和根系分泌能力显著高于一般基因型,且根际细菌和真菌数量与主要根系分泌物的分泌量变化基本保持一致。富钾基因型R104和K12根系CEC和H+分泌量高于一般基因型M9和Cr047,而相同基因型内各品种间的变化不显著。

Under deficient potassium soil culture and different potassium water culture, the changes of contents of different potassium forms were studied, which were in the soil of rhizosphere and non-rhizosphere in different grain amaranth genotypes. While the changes were investigated, which were in the quantities of microorganisms in rhizosphere, rates of important root exudates and H^+ secretion and CEC of roots. The results were indicated that the content of available and slowly available potassium in rhizosphere was higher than that in non-rhizosphere, which formed a area enrichment in potassium comparatively in the rhizosphere. The ability of accumulated potassium in the enrichment genotype was significantly higher than in the common genotype. The content of total potassium of soil in rhizosphere was lower than in the non-rhizosphere , the decreasing extent of total potassium in enrichment genotype was higher than in the common genotype. Compared with the common genotype, the quantities of microorganism in rhizosphere and the exudation rates of main root exudates in enrichment genotype were higher significantly, while the changes of the quantities of bacterium and fungi in rhizosphere was same as the root exudates. CEC of root and the rates of H^+ secretion in enrichment genotype were higher than in common genotype, but they were not significant difference in varieties of the same genotype.