苯并噻二唑处理提高低温贮藏期间马铃薯块茎抗病性及机制分析

Resistance of Potato tubers to Disease Induced by BTH and Its Mechanism during storage at low temperature

以‘陇署10号’为试材，研究了不同浓度苯并噻二矬（benzothiadiazol,BTH采后喷施处理对低温贮藏期间马铃薯块茎干腐病及细菌性软腐病的影响；并分析处理对块茎抗病性相关酶活力、总酚及木矮素的含量的影响，试验结果表明：BTH处理后，块茎在长期低温贮藏过程中干腐病及细菌性软腐病的发生程度均降低，在贮藏后第180天,25ppm和200ppmBTH处理组块茎干腐病的发病率分别较同期对照组降低了51.87％和24．72％。干腐病病情指数分别降低769．55％和57．66％,细菌性软腐病的发病率分别降低774．65％和34．30％，细菌性软腐病病情指数分别降低785．33％和54．72％。BTH处理能增加块茎β—1．3葡聚糖酶、几丁质酶、苯丙氨酸解氨酶、过氧化物酶和多酚氧化酶的活力，提高总酚和木质素的含量水平，其中，25ppm的BTH处理效果最好。BTH处理诱导马铃薯块茎提高了其在低温贮藏期间的抗病性。

The potato cultivar ＇Longshu No. 10＇ were used as experimental material to evaluate the efficacy of benzothiadiazole sprayed in controlling dry rot and bacterial soft rot incidence during storage at low temperature. The effects of B TH sprayed on the contents of total phenolics, lignin , and the activities of resistance-related enzymes were analyzed. The results indicated that BTH treatment could significantly reduce the decay rate and the disease index of dry rot and soft rot after 180d of storage. BTH treatments could also increase the activities of β- 1,3-glucanase （GLU）, chitinase （CHI）, phenylalanine ammonialyase （PAL）, peroxidase （POD） and polyphenol oxidase （PPO） in the tubes. Both B TH could promote the contents of total phenolics and lignin. Therefore, BTH could be effective in inducing postharvest disease resistance in potato tubes during storage at low temperature.