Document Type: Research Paper
Ph.D. student, Department of Agronomy, Faculty of Agriculture, Urmia University, Urmia, Iran.
Associate Professor, Department of Agronomy, Faculty of Agriculture, Urmia University, Urmia, Iran.
The relationship between arbuscular mycorrhizal fungi (AMF) and their associated bacteria
can be has great importance for sustainable agriculture especially in the case of highly
mycorrhizal plants such as linseed. To evaluate the possible effect of AMF in association with
phosphate solubilizing bacteria (PSB) on linseed plants, a 2-yr factorial experiment was
conducted based on a randomized complete block design with three replications at Urmia
University, Urmia, Iran (37° 39′ 24.82″ N 44° 58′ 12.42″ E). The treatments included two AMF
species (Glomus mosseae, G. intraradices and non-mycorrhizal control), PSB (Pseudomonas
putida P13 and non-inoculated control) and various irrigation regimes (irrigation after 60, 120
and 180 mm of evaporation from Class A pan). A significant increase in mycorrhizal linseed
plants yield indicated the effectiveness of the two AMF species more than bacterial inoculation.
The cumulative (second year) soil spores were maximally observed in mycorrhizal (single AMF
and dually inoculation) treatments. The reduction in bacterial population was found with an
increase in water deficit. Dual infections caused an increase in leaf P content more than the one
in PSB and AMF inoculations. Drought stress-induced yield reduction in seed and in oil was
significantly compensated by mycorrhizal symbiosis for all irrigation levels. We found over
25% increase for seed yield and 30% for oil yield in mycorrhizal plants as well as co-inoculated
plants. The yields improvements in mycorrhizal treatments (single and dually inoculated)
leading to the highest water use efficiency.