BION诱导小麦幼苗抗叶锈病研究

研究了BION（有效成分为苯并噻二唑,BTH）对小麦幼苗叶锈病的诱导抗性与苯丙氨酸解氨酶（phenylalanine ammonia lyase,PAL）、多酚氧化酶（polyphenoloxidase,PPO）和过氧化物酶（peroxidase,POD）活性的关系.结果表明：BION诱导麦苗抗叶锈病的最佳浓度为200 mg/L;在诱导处理和接种之间至少需要2天才能诱导抗性表达,间隔4天的诱导抗性效果最好,这种抗性的持久期至少14天.BION处理麦苗第1叶,可使未处理的第2叶也表现出抗性,但处理后至少需要48h这种抗性才能表达.以浓度为200mg/L的BION处理小麦叶片4天后接种,PAL、PPO、POD的活性均高于对照,在接种2天后产生一个峰值,BION水溶液对小麦叶锈菌夏孢子的萌发无明显抑制作用.由此认为,BION可诱导小麦幼苗产生对叶锈病的系统获得抗性.

Induced resistance of wheat seedlings to Puccinia triticina by BION treatment

The induced resistance of wheat seedling to leaf rust was tested while spraying with BION (benzo (1,2,3) thiadiazole-7-carbothioic acid S-methyl ester, BTH). The results indicated that the optimum concentration of BION was 200mg/L for the induction of leaf rust resistance on wheat seedling. The induced activity produced at least two days after spraying with BION while inoculated with challenge pathogen, Puccinia triticina, and could last at least for fourteen days once induced. The highest induction effect was obtained on four days later after spraying with BION. The second leaves of wheat seedlings could produce the induced resistance to leaf rust while the first leaves were sprayed with BION, which could be detected at 48 hours post-spraying. The induced resistance with BION was not able to change the infection type of leaf rust in wheat seedling stage, but the number of leaf rust uredia could be significantly reduced on the second leaves. The activities of phenylalanine ammonia lyase (PAL), polyphenoloxidase (PPO) and peroxidase (POD) on the wheat leaves sprayed with BION at the concentration of 200mg/L were higher than that on the untreated ones. Three peaks of PAL, PPO and POD activities appeared on the second day after treated with BION while inoculated with Puccinia triticina on Zhengzhou 891. The germination of urediniospores could not be inhibited by BION in vitro. So,it is concluded that BION-induced resistance against wheau leaf rust is most likely to be a response of systemic acquired resistance.