Changes in Soil Phosphorus Availability and Microbial Community Structures in Rhizospheres of Oilseed Rapes Induced by Intercropping with White Lupins

Abstract

Oilseed rape is sensitive to soil phosphorus deficiencies. In contrast, white lupin is widely used as a model plant because it has efficient phosphorus utilization. Therefore, soil fertility and microbial composition in the rhizospheres of oilseed rapes and root exudate metabolites were compared under monocropping and intercropping systems. The main purpose was to explore whether the phosphorus absorption of rapeseed can be promoted by intercropping with white lupine. In comparison with oilseed rape monoculture (RR), the results showed that the contents of soil-available phosphorus, microbial biomass and phosphorus in the rhizospheres of oilseed rapes in the intercropping system (RL) were all higher than those of RR. Meanwhile, in comparison with RR, not only phosphorus-solubilizing bacteria, such as Streptomyces, Actinomadura and Bacillus, but also phosphorus-solubilizing fungi, such as Chaetomium, Aspergillus, Penicillium, were enriched in the rhizospheres of the oilseed rape under the RL system. Moreover, more abundant soil bacterial functions, organic acids and metabolites were also detected in root exudates of the oilseed rapes under the RL system. All of the above results suggest that soil phosphorus availability in the rhizospheres of oilseed rape could be improved by intercropping with white lupin. Additionally, soil phosphorus-solubilizing microorganisms, that are enriched in the rhizospheres of oilseed rapes under RL systems, have an important function in the improvement of phosphorus absorption of rapeseed by intercropping with white lupin.

Effects of oilseed rape green manure on phosphorus availability of red soil and rice yield in rice–green manure rotation system

“…Studies have shown that planting oilseed rape can reduce the conversion of soil available phosphorus into O–P and make Ca–P in acidic soil more bioavailable and improve the effectiveness of soil phosphorus ( Gu et al., 2023 ; Yuan et al., 2023 ). During the growth of oilseed rape green manure, root exudates can activate insoluble nutrients in the soil and increase the concentration of available nutrients in the soil, including phosphorus ( Vives-Peris et al., 2020 ; Chen et al., 2023 ). In this study, the soil available phosphorus content of the two oilseed rape green manure treatments was higher than that of the WT, and the BJ was significantly higher than the WT by 11.12%.…”

Annual Weeds Suppression and Oat Forage Yield Responses to Crop Density Management in an Oat-Cultivated Grassland: A Case Study in Eastern China

“…It indicated that both plant species and interspecific competition can change the abundance of dominant bacteria, which is due to their adaptability to a new microenvironment [57,58]. Moreover, the beneficial species (i.e., Bacillaceae, Xanthobacteraceae, Streptomycetaceae, Paenibacillaceae, Planococcaceae, Micromonosporaceae) can favor plant growth and improve nutrient availability by stimulating plants to secrete auxin while simultaneously fixing nitrogen, solubilizing phosphate, and decomposing organic matter [59][60][61][62][63][64]. Apart from their ability to stimulate plant growth, Bacillaceae, Streptomycetaceae, and Geodermatophilaceae can prevent plants from soil-borne disease and abiotic stresses (e.g., drought) through the synthesis of substances akin to lipopeptides that make plants more resistant to external stresses [65,66].…”

Maize/soybean intercropping increases nutrient uptake, crop yield and modifies soil physio-chemical characteristics and enzymatic activities in the subtropical humid region based in Southwest China

“…From all the studies, it is evidently shown that intercropping significantly enhanced plant N uptake, which was attributed to the N fixation ability of legumes, underlying facilitative root interaction/nutrient sharing between intercrops, improved soil nutrient availability, rich availability of soil beneficial microbes and changes occuring in soil rhizosphere because of different chemical released by plant roots [19,63]. Changes in the underlying soil environment in maize-soybean intercropping may also potentially affect the plant and soil-accessible phosphorous (P), because of the chemical substances (i.e., acid phosphatase and The color gradients represent the positive and negative relationship, while the * indicates the significance level at LSD (p ≤ 0.05) level of probability phytase) release by plant root [64], rhizosphere soil acidification as well as a reduction in the soil pH [65], enrichment of P solubilizing bacteria [66], and root exudation [52], which modified the soil rhizosphere, help in P solubilization, mineralization, and mobilization, improve soil Olsen P, and its uptake by plants [9]. For example, the increased P uptake by 20.1% in maize-soybean/peanut intercropping over mono-cropping was mainly because of underlying changes in the soil such as both plant roots and soil microbes release organic acids and extracellular enzymes to activate soil insoluble P and its use efficiency [67].…”