Chin J Plant Ecol ›› 2023, Vol. 47 ›› Issue (6): 782-791.DOI: 10.17521/cjpe.2022.0185

• Research Articles • Previous Articles     Next Articles

Carbon transport and phosphorus uptake in an intercropping system of Robinia pseudoacacia and Amorphophallus konjac mediated by arbuscular mycorrhizal hyphal networks

HE Fei1,*(), LI Chuan1, Faisal SHAH2, LU Xie-Min1, WANG Ying1, WANG Meng1, RUAN Jia1, WEI Meng-Lin1, MA Xing-Guang1, WANG Zhuo1, JIANG Hao1   

  1. 1School of Modern Agriculture & Biotechnology, Ankang University, Ankang, Shaanxi 725000, China
    2Department of Agronomy, The University of Agriculture, Peshawar (UAP), Peshawar, Khyber Pakhtunkhwa 23060, Pakistan
  • Received:2022-05-09 Accepted:2022-10-10 Online:2023-06-20 Published:2022-10-10
  • Supported by:
    National Natural Science Foundation of China(31901468);Key Research and Development Program of Shaanxi Province(2021NY-048);Innovation Capacity Support Plan of Shaanxi Province(2020KJXX-003)


Aims The aim of this research was to clarify the effects of intercropping and inoculation with arbuscular mycorrhizal fungi (AMF) on carbon transport and phosphorus uptake in black locust (Robinia pseudoacacia) and konjac (Amorphophallus konjac). The results could provide empirical evidence to reveal the mechanisms of black locust intercropping for disease control and plant growth promotion of konjac, and popularize the green and high-yielding cultivation technique of konjac under black locust.

Methods The experiment was carried out in two-compartment rhizoboxes separated by a 25-μm nylon net, each of which comprised compartment A (non-inoculated or AMF-inoculated black locust) and compartment B (monocropped black locust or intercropped konjac). A 13C stable isotope labeling technique was used to label the leaves of black locust in compartment A with 13CO2. Carbon transport from black locust to konjac and the effects of AMF colonization on agronomic traits, 13C abundance, and phosphorus content in both crops were investigated.

Important findings The result showed that: (1) After inoculation, the AMF infection rate of black locust and konjac plants by hyphal links in compartment B reached 47.1% and 60.4%, respectively. For black locust, this AMF infection rate was 14.1% lower than that of directly inoculated plants under monocropping. In the case of intercropping, the biomass (dry mass) of AMF-inoculated konjac plants was 9.7% (aboveground parts) and 36.2% (belowground roots) higher than that of non-inoculated plants. (2) Compared with the non-inoculated plants under monocropping, the carbon fixed by photosynthesis of black locust plants in other treatments (non-inoculated + intercropping, inoculated + monocropping, and inoculated + intercropping) was mainly allocated to the plant roots and rhizosphere soil in compartment A, and more carbon passed through the nylon net in the form of root exudates to reach the rhizosphere of neighboring crop plants. (3) Compared with the respective non-inoculated controls, AMF inoculation in the monocropping and intercropping systems prominently improved phosphorus contents in the leaves, stems/petioles, roots, and total plants of black locust and konjac in compartment B. The findings suggest that AMF colonization could facilitate carbon transport from black locust to the rhizosphere soil and plant tissues of konjac. Intercropping konjac with black locust is an effective practice to promote AMF colonization and phosphorus uptake by both host plants.

Key words: Robinia pseudoacacia, Amorphophallus konjac, arbuscular mycorrhizal fungi, 13C abundance, root exudate