AMF对铁尾矿区草本植物生长参数、营养吸收及种间竞争的影响

Effects of arbuscular mycorrhizal fungi on growth parameters, nutrient absorption, and interspecific competition of herbs on iron tailings

采用温室盆栽试验研究了丛枝菌根真菌(AMF)摩西球囊霉(Funneliformis mosseae)(FM)和3种不同种植模式对铁尾矿白三叶(Trifolium repens)和黑麦草(Lolium perenne)生长参数、矿质营养吸收及种间竞争的影响,以期筛选一种既能增强植物定植的能力又能提高尾矿先锋植物重建的栽培模式,为铁尾矿废弃地的植物恢复提供理论依据和应用基础。结果表明,菌根真菌FM与两种植物建立了互惠共生关系,混合种植下具有较高的根际菌根侵染率,其中混合种植白三叶的根际菌根侵染率最高,平均为47.9%。接种FM显著提高了白三叶磷含量(168%~357%)(P <0.05)和混种模式下黑麦草磷含量(10.5%)(P <0.05);显著增加了白三叶生物量(5~7倍)(P <0.05)和混种模式下黑麦草生物量(1.9倍)(P <0.05)。混合种植下植物铁含量显著高于单种,而接种FM显著降低了白三叶地上部铁含量(P <0.05),对地下部铁含量影响呈相反趋势。接种FM提高了白三叶铁吸收量,提高了单种模式下黑麦草铁吸收量,显著降低了混种模式下黑麦草铁吸收量(P <0.05)。混合种植模式下两种植物具有较高的铁吸收效率,且接种FM显著提高了白三叶铁吸收效率(P <0.05),降低了黑麦草铁吸收效率。混合种植模式显著增加了白三叶锌含量,而降低了铜含量。接种FM显著降低了两种植物锰含量,而显著增加了白三叶铜含量。白三叶与黑麦草混种体系土地当量比大于1,具有混种优势。两种植物混合种植情况下黑麦草显示了相对竞争优势,而菌根共生体能够提高白三叶的竞争能力。综合来看,混合种植能够显著促进黑麦草生长,而接种FM能增强白三叶的竞争能力;丛枝菌根真菌对先锋植物适应铁尾矿复合逆境及尾矿先锋植被修复具有较大潜力。

The greenhouse pot experiment was used to study the effects of the arbuscular mycorrhizal fungus(AMF)Funneliformis mosseae(FM) and three different planting patterns on growth parameters, mineral nutrient absorption, and inter-species competition of white clover(Trifolium repens) and ryegrass(Lolium perenne) on iron tailings. This study aimed to identify a type of cultivation mode that could not only increase plant colonization but also improve the introduction of pioneer plants in tailings and to provide a theoretical and application basis for plant restoration on iron tailing wasteland. The results showed that FM could establish a symbiotic with the two other plant species and had a higher rhizosphere mycorrhizal infection rate under mixed planting. The rhizosphere mycorrhizal infection rate of mixed planting white clover was the highest, with an average of 47.9%. Inoculation with FM significantly increased the phosphorus concentrations in white clover(168% ~ 357%)(P < 0.05) and the phosphorus concentrations in ryegrass in mixed planting(10.5%)(P < 0.05) as well as the biomass of white clover(by approximately 5 ~ 7 times)(P < 0.05) and ryegrass in mixed mode(1.9 times)(P < 0.05). In mixed planting, plant iron concentrations were significantly higher than that in single species. FM inoculation significantly decreased the iron concentrations in shoots of the white clover(P < 0.05), but the iron concentration in their roots increased.FM inoculation increased the iron absorption of white clover and ryegrass under the single mode and significantly decreased the iron absorption of ryegrass under the mixed mode(P < 0.05). In the mixed planting mode, the two plants had higher iron absorption efficiency, FM inoculation significantly increased the iron absorption efficiency of white clover(P < 0.05) and decreased that of ryegrass. The mixed planting mode significantly increased the zinc concentrations and decreased the copper concentrations of white clover. FM inoculation significantly decreased the manganese concentrations of two plants and significantly increased the copper concentrations of white clover. The white clover and ryegrass hybrid system has a land equivalent ratio greater than 1, which has a mixed advantage. The interspecific competitive ability of ryegrass compared with white clover was greater than 0, indicating a competitive advantage. Mycorrhizal fungi may improve the competitive ability of white clover. Mixed planting can, therefore, significantly promote the growth of ryegrass, whereas inoculation with FM can enhance the competitiveness of white clover. AMFs have great potential for use with pioneer plants to adapt to the complex adversity of iron tailings and to restore tailings pioneer vegetation.