[Effects of endophytic Paenibacillus polymyxa S-7 on photosynthesis, yield, and quality of sugar beet].

This study showed that inoculation of endophytic Paenibacillus polymyxa S-7 could significantly (P < 0.05) promote the photosynthesis of sugar beet. After the inoculation, the leaf net photosynthetic rate (Pn), stomatal limitation (Ls), stomatal conductance (Gs), and transpiration rate (Tr) increased by 16.11%, 23.82%, 41.91%, and 34.80%, respectively, while the stomatal intercellular CO2 concentration (Ci) decreased by 21.09%. Inoculation of endophytic P. polymyxa S-7 could also increase sugar beet yield and its quality significantly (P < 0.05), with the tuberous root biomass and its sugar content increased by 25.63% and 17.46%, respectively. It was concluded that endophytic P. polymyxa S-7 not only affected the photosynthetic parameters, but also promoted the yield and quality of sugar beet.