Are arbuscular mycorrhizal fungi intervening in the facilitation of soybean invasion in Americas?

COVACEVICH, F; CABELLO, MN; FAGGIOLI, VS

Norwich

Workshop; Next generation scientists 2017; 2017

New Phytologist

Soybean is an annual plant originated in Asia and occupies c. 90% of Argentinean agricultural area. Arbuscular mycorrhizal fungi (AMF) have been reported as strongly synergistic with exotic plants colonizing new areas of the world. The objective of this work was to evaluate mycorrhizal status of soybean fields and the effect of resident AMF on plant growth and development. Samples of 125 soybean fields were taken from geographic and intensity land use gradients. Mycorrhizal status was estimated by mycorrhizal colonization, spore identification, and pyrosequencing. The effect of resident AMF on plants was studied in pot experiments under contrasting conditions. We found that 99% of soybean roots were mycorrhizal with a range of 40-61% -. A total of 36 AMF species were identified. Pyrosequencing yields 84 and 74 virtual taxa in soil and root samples, respectively. In spite of contrasting geographical conditions growth parameters did not differ among sites. Pot experiment revealed that soybean plants improved growth and development under AMF presence whether or not limiting conditions occurred. It is proposed that the spread of this non-native plant species could be facilitated by resident AMF, underlining the need to integrate symbiotic interactions in future work on soybean adaptability processes.