Biological Characteristics and Herbicidal Activity of Metabolites Produced by Bipolaris sorokiniana from Eleusine indica

Abstract:

The biological characteristics of Bipolaris sorokiniana strain NJ-08 and herbicidal activity its metabolites was tested. The results showed that NJ-08 displayed excellent pathoginicity and high sporulation. The optimum temperature and pH for mycelial growth was 25°C and 8 respectively, the lethal temperature was 55°C maintaining 10 min, the glucose was the best among carbon sources for mycelial growth but all nitrogen source did not significantly promote mycelia growth. For sporulation, the optimum temperature and pH was 25°C and 8, the glucose was the best carbon sources and NaNO3 was the best nitrogen sources. For spore germination, the ranges were temperature of 20°C~35°C and pH of 5~7, while D-xylose was the best carbon sources and peptone was the best nitrogen sources. The metabolites produced by NJ-08 strain made the leaves of Eleusine indica yellow and wilting, and showed good herbicidal activity against the indicator plant and weeds such as Stylosanthes guianensis, Urena lobata, Crotalaria mucronata and Capsicum frutescens with the inhibition rate to radicel and embryo of above 90%.