贝莱斯芽孢杆菌HN-Q-8与化学药剂协同防治马铃薯黑痣病OA

Potato black scurf,a soil-borne disease,is caused by R.solani.The combined use of biocontrol agents and chemical fungicides for plant disease control can reduce pesticide residues while achieving efficient disease control.This study investigated the synergistic effect of B.velezensis HN-Q-8 and four chemical fungicides(25%Ningnanmycin·azoxystrobin,45%Thifluzamide·azoxystrobin,30%Ningnanmycin·tebuconazole,and 25%azoxystrobin)against potato black scurf.25%Ningnanmycin·azoxystrobin and 45%Thifluzamide·azoxystrobin exhibited good compatibility with HN-Q-8.The significant synergistic effects on the inhibition of black scurf were observed when 45%Thifluzamide·azoxystrobin was combined with HN-Q-8 at volume ratios of 1∶9 and 2∶8,and when 25%Ningnanmycin·azoxystrobin was combined with HN-Q-8 at a volume ratio of 7∶3.The corresponding synergistic ratios(IR)for disease inhibition were 1.31,1.13,and 1.12,respectively.Furthermore,through evaluation of growth-promoting effects,it was found that the combination of 25%Ningnanmycin·azoxystrobin and HN-Q-8 at a 7∶3 volume ratio effectively promoted the colonization of HN-Q-8 in the soil and exhibited the best growth-promoting effect,with increases in plant height,stem girth,and root length of 53.62%,21.60%,and 27.27%,respectively,compared with the water control group.Based on these results,five field control schemes were designed using a mixture of 25%Ningnanmycin·zoxystrobin and strain HN-Q-8.In scheme 1,the 25%Ningnanmycin·zoxystrobin to HN-Q-8 volume ratio was 7∶3,and applied once in the furrow before sowing,achieved a control efficacy of 91.67%.When considering factors such as overall cost,this scheme is recommended as the optimal field control strategy.Therefore,the synergistic application of chemical fungicides and biocontrol bacteria could effectively control potato black scurf and facilitate the sustainable development of the potato industry.