Arbuscular mycorrhizas modify tomato responses to soil zinc and phosphorus addition
- 574 Downloads
Arbuscular mycorrhizas (AM) play an important role in plant P and Zn nutrition; however, relatively few studies have directly investigated the interactive effects of these nutrients on plants. Therefore, we undertook a glasshouse experiment to study the effects of Zn and P on AM formation and functioning. A mycorrhiza defective tomato mutant (rmc) and its mycorrhizal wild-type progenitor (76R) were used in this experiment. Plants were grown in soil amended with five Zn concentrations, ranging from deficient to toxic, and two levels of P addition. The addition of Zn and P to the soil over a range of concentrations had profound effects on plant growth and nutrition and mycorrhizal colonization. Mycorrhizal benefits were the greatest when plants were grown under low soil P and Zn. Furthermore, the effect of soil Zn supply on plant growth, nutrition, and AM colonization was strongly influenced by the concentration of P in the soil. Thus, studies of AM and Zn (or other nutrients of interest) should take into account the impact of soil P concentration on the role of AM in plant Zn acquisition, under both deficient and toxic soil Zn concentrations.
KeywordsArbuscular mycorrhizas (AM) Zinc Phosphorus Mycorrhiza defective tomato mutant (rmc) Solanum lycopersicum (Tomato)
The authors wish to thank Ms. Leesa Hughes for her excellent technical assistance and members of the “Cav-Lab” for valuable discussions. We also gratefully acknowledge Dr. Susan Barker and Prof. Sally Smith for continued access to the rmc and 76R genotypes of tomato. This research was in part funded by the Monash University, School of Biological Sciences. TRC also wishes to acknowledge the Monash Research Accelerator program for financial support.
- Brown KH, Wuehler SE (2000) Zinc and human health: results of recent trials and implications for program interventions and research. International Development Research Center, OttawaGoogle Scholar
- Cavagnaro TR, Smith FA, Hay G, Carne-Cavagnaro VL, Smith SE (2004) Inoculum type does not affect overall resistance of an arbuscular mycorrhiza-defective tomato mutant to colonisation but inoculation does change competitive interactions with wild-type tomato. New Phytol 161:485–494CrossRefGoogle Scholar
- Epstein E, Bloom AJ (2005) Mineral nutrition of plants: principles and perspectives, 2nd edn. Sinauer Associates, SunderlandGoogle Scholar
- Godbold DL, Horst JW, Marschner H, Collins JC, Thurman DA (1983) Root growth and zinc uptake by two ecotypes of Deschampsia cespitosa as affected by high zinc concentrations. Z Pflanzenphysiol 112:315–324Google Scholar
- Marschner H (1995) Mineral nutrition of higher plants, 2nd edn. Academic, San DiegoGoogle Scholar
- Marschner H, Dell B (1994) Nutrient uptake in mycorrhizal symbiosis. Plant Soil 159:89–102Google Scholar
- Martin AW (2007) The role of arbuscular mycorrhizal fungi in sustainable tomato production. Dissertation, The University of Adelaide, AdelaideGoogle Scholar
- Reuter DJ, Robinson JB (1997) Plant analysis: an interpretation manual, 2nd edn. CSIRO, MelbourneGoogle Scholar
- Robson AD, Pitman MG (1983) Interactions between nutrients in higher plants. Encyclopedia plant physiology new series, vol 15A. Springer, BerlinGoogle Scholar
- Smith SE, Read DJ (2008) Mycorrhizal symbiosis, 3rd edn. Academic, CambridgeGoogle Scholar
- Zar JH (1999) Biostatistical analysis, 4th edn. Prentice Hall, Upper Saddle RiverGoogle Scholar