水杨酸诱导苜蓿对霜霉病抗性的研究

对陇东苜蓿、大叶苜蓿、甘农3号和关中苜蓿4个感霜霉病品种进行了水杨酸喷雾试验,研究了水杨酸对苜蓿霜霉病的诱导抗性．结果表明,陇东苜蓿的诱导抗病效果最好,诱导效果可达61．8％,用不同浓度的SA诱导处理陇东苜蓿幼苗发现,SA诱导的最宜浓度为50μg／μL;SA诱导处理后,苜蓿幼苗体内过氧化物酶(POD)和苯丙氨酸解氨酶 (PAL)活性明显增强,POD、PAL在处理后第7 d、第5 d达到最大,分别为9．8(μ／g·hfw)和4．87(△OD／0．01 gfw),是对照的2．5倍和3．2倍．

Study on resistance of alfalfa to downy mildew induced by SA

Four downy mildew susceptible alfalfa cultivars, Longdong, Daye, Gannong No. 3 and Guanzhong,were sprayed by salicylic acid (SA) ,and the effects of SA on resistance induction were studied. The best resistance induction effect was on alfalfa Longdon,it was 61.8 %. Inducing seedlings of alfalfa Longdong with SA of different concerntration,it was showed that the optimum concerntration of SA was 50 μg/μL. The activities of POD and PAL in alfalfa seedlings were obviously increased and reached the maximum,9. 8 μ/g·hfw and 4. 87 △OD/0.01 gfw ofter treated with SA for seven days and five days respectively, which was 2. 5 times and 3. 2 times as much as control respectively.