硅酸钠对马铃薯黑痣病的抗性及其抗性相关物质的影响

Effects of sodium silicate on resistance to potato stem canker and its resistance-related substances

为明确硅酸钠对马铃薯黑痣病抗性及其抗性相关物质的影响,采用盆栽法在接菌和不接菌情况下施硅酸钠,调查不同处理下马铃薯地下茎和匍匐茎的发病情况,并测定与抗性相关的7种酶活性及木质素含量。结果表明,接菌8 d时,施硅酸钠的马铃薯幼苗地下茎和匍匐茎病情指数分别比不施硅酸钠的降低42.9%和67.2%;接菌12 d时,施硅酸钠的马铃薯幼苗地下茎和匍匐茎病情指数分别比不施硅酸钠的降低55.7%和50.0%。施硅酸钠4~6 d,硅酸钠可诱导马铃薯幼苗体内过氧化物酶(peroxidase,POD)活性升高;不接菌处理时硅酸钠能减缓多酚氧化酶(polyphenol oxidase,PPO)活性降低;硅酸钠对马铃薯幼苗体内苯丙氨酸解氨酶(phenylalanine ammonia-lyase,PAL)活性无影响;不接菌处理14~16 d时硅酸钠能提高马铃薯幼苗体内超氧物歧化酶(superoxide dismutase,SOD)活性,接菌处理时硅酸钠对马铃薯幼苗体内SOD活性无影响;施硅酸钠第10天,马铃薯幼苗体内过氧化氢酶(catalase,CAT)活性升高;施硅酸钠处理第2天,马铃薯幼苗体内几丁质酶和β-1,3-葡聚糖酶活性升高,不接菌处理10~14 d时施硅酸钠降低β-1,3-葡聚糖酶活性;硅酸钠对马铃薯幼苗的木质素含量无影响。

To clarify the effects of sodium silicate on the resistance to potato stem canker and the resistance-related substances,sodium silicate was applied in inoculated and non-inoculated potato seedlings with Rhizoctonia spp.in pots;the severity of underground stems and stolons were investigated,and the activities of seven resistance-related enzymes,and lignin contents were determined.The results showed that the severity of potato stem and stolon canker was significantly lower than that of in the treatment without sodium silicate eight days after treated with sodium silicate in inoculum,and the reduction percentages were 42.9%and 67.2%,respectively.At day 12 after treated with sodium silicate,the reduction percentages for stem and stolon canker were 55.7%and 50.0%,respectively.The detection results of resistance-related substances indicated that,in four to six days after treated with sodium silicate,sodium silicate could increase peroxidase(POD)activity of inoculated and non-inoculated potato seedlings,slow down the decrease of polyphenol oxidase(PPO)activity of the non-inoculated potato seedlings.Sodium silicate did not affect the phenylalanine aminolase(PAL)activity in the whole treatment time.In 14 to 16 days after treatment,the superoxide dismutase(SOD)activity was increased by sodium silicate in inoculated potato seedlings,but not in non-inoculated of potato seedlings.At day 10 after treatment with sodium silicate,the catalase(CAT)activity of potato seedlings was increased by sodium silicate in inoculation and non-inoculation treatments.At day 2 after treatment,chitin enzyme andβ-1,3-dextran enzyme activities were increased by sodium silicate in inoculation and non-inoculation treatments,and at day 10 to 14,β-1,3-dextran enzyme activity was reduced by sodium silicate in non-inoculated potato seedlings.The application of sodium silicate did not affect the lignin content.