Co-Inoculation of Bradyrhizobium spp. and Bacillus sp. on Tarwi (Lupinus mutabilis Sweet) in the High Andean Region of Peru

Abstract

Tarwi (Lupinus mutabilis Sweet) is an Andean legume that has attracted international interest due to its high nutritional value. This has resulted in an increase in its conventional production, which leads to an ecological imbalance. In this context, the application of biotechnologies, based on the use of bacterial inoculants, is of utmost importance. This work aimed to evaluate the effects of a consortium of 2 strains of Bradyrhizobium spp. (BR) and 1 strain of Bacillus sp. (BA) on tarwi var. Andenes. The treatments tested were BR + BA, BR + Organic Matter, BR + Agrochemical (Azoxystrobin y Difenoconazole), and the control (without application). The crop was located in Marcara-Ancash (altitude 3254 masl), Peru. The experiment involved the inoculation of BR in the seeds and a re-inoculation 30 days later. BA was inoculated every 30 days in the neck of the plant and aerial part, 5 times during plant development. The inoculation with BR + BA significantly increased the aerial fresh weight (413.2%), plant height (13.5%), and diminished the anthracnose (38.4%) of plants 110 DAS (days after the sowing). Also, this treatment produced the best-harvested emergence percentage (97.9%), morpho-agronomic characteristics, and an increase in the yield (171%) compared to the control. In conclusion, the application of the Bacillus sp. strain and the Bradyrhizobium spp. consortia improved the productivity of tarwi var. Andenes. The interaction of these strains have the potential to be used in tarwi field planting programs.