Screening of Arbuscular Mycorrhizal Fungi for Symbiotic Efficiency with Sweet Potato

ABSTRACT

A greenhouse study was conducted to study the efficiency of 14 isolates of arbuscular mycorrhizal (AM) fungi isolated from a local agricultural soil on the productivity of sweet potato (Ipomoea batatas). The different AM fungi enhanced the biomass and nutritional status of sweet potato seedlings to different extents. The genus Glomus was more effective than Acaulospora or Scutellospora. Efficiency also varied among isolates of Glomus irrespective of individual host plant or location of origin. Intraspecific differences were sometimes greater than interspecific differences. Benefits deriving from fungal isolates were positively correlated with the root-colonization rate and the abundance of extraradical propagules of the AM fungi. Taking plant yield parameters, nutritional status of the plants, and fungal attributes into consideration, GEGM (Glomus etunicatum together with Glomus mosseae) and GE6 (Glomus etunicatum) were the most effective AM symbionts for sweet potato under the experimental conditions.

Keywords:

• mycorrhizal efficiency
• arbuscular mycorrhizal
• sweet potato

ACKNOWLEDGMENTS

We thank the European Commission (FP5-INCO-2-ICA4-CT2000-30014) for financial support.

Notes

∗Isolates GE5 and SG were derived from the same soil sample

∗∗isolates GE3 and GM2 were obtained from the same soil sample.