The potential of corn-soybean intercropping to improve the soil health status and biomass production in cool climate boreal ecosystems

Intercropping (IC) is a promising approach used to improve soil health and sustainable crop production. However, it is unknown whether IC improve the soil health status and biomass productivity of crops cultivated in podzols under cool climate in boreal ecosystems. Two silage corn and three forage soybean genotypes were cultivated either as inter or monocrop (MC) treatments in a randomized complete block design. IC resulted in 28% increase in total forage production (FP). A reduction in rhizosphere soil pH (RS-pH) was observed in the IC treatments. Conversely, the rhizosphere soil acid phosphatase (RS-APase) activity was significantly higher (26–46%) in the IC treatments and occurred concomitant with a significant increase in available phosphorus (RS-P(available)) (26–74%) in the rhizosphere. Furthermore, IC enhanced the active microbial composition and strong positive correlations were observed between RS-P(available), RS-APase, microbial biomass and FP; while RS-pH was negatively correlated with FP, RS-APase and RS-P(available). These findings suggested silage corn intercropped with forage soybean could be a viable approach to enhance FP through improved active microbial community structure, RS-APase activity and RS-P(available) when cultivated on podzols in cool climate boreal ecosystem.