Effect of Phosphorus Application and Arbuscular Mycorrhizal Fungi Inoculation on the Growth of American Jointvetch and Greenleaf Desmodium

Manabu Tobisa,Yoshinori Uchida

doi:10.3844/ajabssp.2017.85.94

Abstract

This study examined the growth and Arbuscular Mycorrhizal (AM) colonization of two tropical forage legumes, namely, American jointvetch (Aj) and Greenleaf desmodium (Gd), at two phosphate application rates (0 or 10 g P m-2 yr-1; -P or +P), with or without AM (+AM or -AM) in a pot experiment. AM inoculation and P application promoted the growth of both species. AM inoculation in the early growth stages promoted colonization in both species, but P application did not. Nitrogen and phosphorus concentrations were affected by neither AM inoculation nor P application. Nitrogen uptake in both Aj and Gd, however, was affected by both AM inoculation and P application. Phosphorus uptake was affected by AM inoculation in Aj and by P application in Gd. The results suggest that both P application and AM promoted legume growth and AM colonization was not suppressed by P application. Nevertheless, plant responses to the treatments varied with species and growth stage.

Highlights

Arbuscular Mycorrhizal (AM) fungi form symbiotic associations with more than 80% of land plant families
In the first analysis of American jointvetch (Aj), the Dry Matter (DM) weights of the stem, leaf, shoot, root and whole plant of Aj were significantly higher in +AM than in -AM (p
For Aj, the highest DM weight was found in the +AM/+P treatment (p

Summary

Introduction

Arbuscular Mycorrhizal (AM) fungi form symbiotic associations with more than 80% of land plant families. Other benefits to the host include improved resistance to foliar-feeding insects, drought and soil pathogens; increased salt and heavy metal tolerance; enhanced uptake of macro- and micronutrients; and changes to soil structure (Smith et al, 2003; Cardoso and Kuyper, 2006; Gosling et al, 2006; Briske, 2007; Smith and Read, 2008; Watts-Williams and Cavagnaro, 2014). When phosphorus is abundant in the soil, the symbiosis between AM and the host plant is less evident and the fungi become parasitic (Gosling et al, 2006; Naher et al, 2013)

Methods

Results

Conclusion