Interspecific Facilitative Root Interactions and Rhizosphere Effects on Phosphorus and Iron Nutrition Between Mixed Grown Chickpea and Barley

ABSTRACT

A glasshouse study was conducted to investigate the effects of interspecific complementary and competitive root interactions and rhizosphere effects on phosphorus (P) and iron (Fe) nutrition of mixed grown chickpea (Cicer arietinum L.) and barley (Hordeum vulgare L.). In order to provide more physiological evidence on the mechanisms of interspecific facilitation, we determined phosphatase activities in plant and rhizosphere, and root ferric reducing capacity (FR), Fe-solubilizing activity (Fe-SA) and rhizosphere pH. The results of the experiment revealed that biomass yield of barley was significantly increased by associated chickpea as compared to monocultured barley, while mixed cropping caused a slight decreases in the biomass yield of chickpea. The rhizosphere was strongly acidified under chickpea and chickpea/barley mixed cropping and this acidification, in turn, increased the available P, Fe(II) and DTPA-Fe concentrations in the rhizosphere. Fe-solubilizing activity (Fe-SA) and ferric reducing (FR) capacity of the roots were higher in both species grown in mixed culture relative to their monoculture which may improve Fe nutrition of both species. Leaf acid phosphatase (APase, EC 3.1.3.2) activity was higher in both plants under mixed cropping that may improve P nutrition of barley by chickpea.

Keywords:

• acid and alkaline phosphatases
• barley
• chickpea
• ferric reducing capacity
• mixed cropping
• Fe-solubilizing activity

ACKNOWLEDGMENTS

This research was carried out by the support of Ankara University, Scientific Research Fund (BAP: Project no. 20030711074).

Notes

∗: P < 0.05,

∗∗: P < 0.01, ns: non-significant.

∗: P < 0.05,

∗∗: P < 0.01,

ns: non-significant, different letter in each row represents significant difference at p ≤ 0.05 level based on Duncan's multiple range test.