Effects of arbuscular mycorrhizal fungi on wheat growth, physiology, nutrition and cadmium uptake under increasing cadmium stress

A pot culture experiment was carried out to study the alterations in growth, biochemical activities and cadmium (Cd) uptake by wheat (Triticum aestivum) inoculated with or without arbuscular mycorrhizal (AM) fungi in sterilized soil with addition of different Cd levels (0, 100, 300, 600 mg.kg_1). In Mycorrhizal (M) plants, root colonization rates were significantly lower with the addition of high Cd concentration (600 mg.kg_1). AM inoculation increased shoot and root biomass at 100 mg kg_1 Cd addition but cause a reduction at 300 and 600mg.kg-1. Shoot and root Cd concentrations in mycorrhizal (M) plants were lower at all levels (0, 100, 300 and 600 mg.kg-1) and Cd accumulation and uptake efficiency were lower in M plants. AM inoculation improved shoot and root P nutrition at all Cd levels. In addition, mycorrhization also cause to improved shoot nutrients uptake (N, P, K, Ca, Mg, Na), chlorophyll, carotene, protein and sugar contents as compared to NM plants. Cd toxicity induced proline accumulation and significant reduction of antioxidant enzyme activities (SOD, POD, CAT, APX) were observed in NM plants however proline contents were lower in M except the higher Cd concentration (600 mg.kg-1). The results support the view that AMF can improve the capability of reactive oxygen species (ROS) and reduce Cd concentration in plants to protect wheat (Triticum aestivum L.) from Cd stress. Hence, AM fungi in combination with wheat is suitable for reduction of Cd toxicity and also shows a potential role in phytostabilization of soil moderately polluted with Cd. * Corresponding Author: Sadia Kanwal  [email protected] International Journal of Agronomy and Agricultural Research (IJAAR) ISSN: 2223-7054 (Print) 2225-3610 (Online) http://www.innspub.net Vol. 7, No. 5, p. 30-42, 2015 International Journal of Agronomy and Agricultural Research (IJAAR) ISSN: 2223-7054 (Print) 2225-3610 (Online) http://www.innspub.net Vol. 5, No. 1, p. 14-22, 2014