Efficiency of Xenorhabdus bovienii in protecting potato (Solanum tuberosum L.) against Rhizoctonia black scurf

Abstract

This research evaluated the efficiency of metabolism products of entomopathogenic nematode symbiotic bacteria (MPEPNSB) of Xenorhabdus bovienii (Enterobacteriaceae) against Rhizoctonia black scurf on potato and effect of MPEPNSB treatment alone and in combination with NPK fertilizers on emergence of plants, yield and biochemical indicators of daughter tuber quality. The field experiment was carried out in 2016 under natural conditions of the Northwest region of Russia on the sod-podzolic loamy soil. The application of MPEPNSB (aqueous suspension, 30 mL/L of water) for the treatment of soil (1000 L/ha), seed tubers (10 L/t) and potato plants in the emergence phase (200 L/ha) inhibited the severity of black scurf by 97 %, the incidence of the disease reduced by 97.6 %. The complex treatment increased the potato plant emergence by 13.8%, yield by 22 %, starch content by 5 % and vitamin C content by 9.3 %. Combined application of MPEPNSB and mineral fertilizers improved yield and tuber quality indicators in potato. Application of MPEPNSB with fertilizers (MPEPNSB + N60P60K90 and MPEPNSB + N90P90K120) increased the potato yield by 55-58 %, starch content by 7.8 % and vitamin C content by 14.5-13.1 %. This study provides a perspective for the use of MPEPNSB for Rhizoctonia black scurf control in potato protection systems. Application of MPEPNSB produced high quality potato tubers.