Effect of mycorrhizal inoculation and phosphorus fertilizer on morphological and physiological traits of fenugreek (Trigonella foenum-graecum L) in arsenic contaminated soil

The aim of this study was to investigate the effect of mycorrhizal species and phosphorus on fenugreek in soils contaminated with heavy metals. The first factor was four levels of mycorrhiza (Glomus mosseae, G. intradices, G. versiform and non-application), the second factor was the three levels of arsenic (0, 15 and 30 mg kg-1 soil), and the third factor was two levels of phosphorus (0 and 250 mg kg-1 soil). In this study, arsenic toxicity was studied on vegetative growth, arsenic accumulation in shoot and root, leaf phosphorus, proline, carbohydrate, chlorophyll index, as well as root colonization percent. Arsenic addition significantly reduced vegetative traits, chlorophyll index, the concentration of phosphorus and nitrogen in the leaves and root colonization percent. The highest level of contamination resulted in an increase of 95,99, 33 and 32% of arsenic in shoots, arsenic in root, proline and carbohydrates compared to control. Application of mycorrhiza and phosphorus also had a significant effect on the other traits except the percentage of colonization. The interaction between arsenic and mycorrhiza on fresh weight of shoot, colonization percentage and shoot arsenic accumulation and interaction of arsenic and phosphorus on shoot fresh and dry weight, fresh and dry weight of root and arsenic accumulation in shoots were significant. In response to the destructive effects of arsenic G. intradices, with an 18% reduction in arsenic accumulation, was better than other species. This experiment showed that mycorrhiza and phosphorus had a moderating effect on the negative effects of arsenic toxicity on traits and could be effective in reducing the negative effects of arsenic stress by improving vegetative growth.