陈明珠 刘国琴 彭丽娟

摘 要：为探明日本外担菌培养液对烤烟幼苗生长及碳氮代谢的影响，以K326为材料，用不同浓度（原液、1/10原液、1/50原液和1/100原液）日本外担菌培养液喷施烤烟幼苗，分析其对烤烟幼苗生长及叶绿体色素含量、根系活力和碳氮代谢关键酶活性的影响。结果表明，处理后3 d，1/50原液处理的幼苗根系活力最高，较对照显著增加276 μg/（g·h）;原液处理的幼苗叶绿体色素含量显著高于对照，叶绿素a、b和类胡萝卜素含量分别增加0.324、0.104和0.060 mg/g。处理后7 d，1/100原液处理的幼苗硝酸还原酶（NR）、谷氨酰胺合成酶（GS）、可溶性淀粉合成酶（SSS）、蔗糖磷酸合成酶（SPS）和蔗糖转化酶（INV）活性最高，较对照显著增加0.36、0.44、5.16、58.02和362.60 U/g;处理后11 d，1/100原液处理的幼苗叶长、叶宽、叶面积和株高显著高于对照，分别增加3.11 cm、1.03 cm、25.39 cm2和5.13 cm。綜合而言，1/100原液浓度促进烤烟幼苗生长的效果最显著，1/50原液次之。

关键词：日本外担菌;烤烟幼苗;生长;根系活力;碳氮代谢

Abstract： To study the effects of Exobasidium japonicum liquid culture on growth and key enzymes of carbon and nitrogen metabolism of flue-cured tobacco seedlings， with K326 as the test material， different concentrations （original solution， 1/10 original solution， 1/50 original solution and 1/100 original solution） of the liquid culture were used to spray the flue-cured tobacco seedlings， the effects on growth， chlorophyll content， root activity and key enzyme activities of carbon and nitrogen metabolism of flue-cured tobacco seedlings were analyzed. The results showed that on the third day after treatment， the root activity of seedlings treated with 1/50 original solution was the highest， which was 276 μg/（g·h） higher than that of CK. Chlorophyll a content， chlorophyll b content and carotenoid content were increased by 0.324， 0.104 and 0.060 mg/g respectively. On the 7th day after treatment， the activities of NR， GS， SSS， SPS and INV of seedlings treated with 1/100 original solution were the highest， which were significantly increased by 0.36， 0.44， 5.16， 58.02 and 362.60 U/g compared with the control. On the 11th day after treatment， leaf length， leaf width， leaf area and plant height of seedlings treated by 1/100 solution were significantly higher than those treated by CK， increased by 3.11 cm， 1.03 cm， 25.39 cm2 and 5.13 cm， respectively. Different concentrations of E. japonicum liquid culture had different effects on tobacco seedlings. In summary， 1/100 original solution concentration promoted the growth of flue-cured tobacco seedlings with the most significant effect， followed by 1/50 original solution.

Keywords： Exobasidium japonicum; tobacco seedlings; growth; root activity; C/N metabolism

外担菌属（Exobasidium）为担子菌门（Basidiomycota）真菌，是重要的植物病原菌，主要寄生杜鹃花科（Ericaceae）、茶科（Theaceae）和樟科（Lauraceae）等木本植物，引起寄主植物产生肿胀、斑点、从枝和菌瘿等症状[1]。阙生全[2]研究发现，油茶受到细丽外担菌（E. gracile）侵染后，叶片中生长素（IAA）和赤霉素（GA3）含量出现先升后降的变化趋势，而脱落酸（ABA）呈先降后升的变化，还发现细丽外担菌培养液中含有IAA和ABA。刘爱英等[3]和郭春秋等[4]研究表明，细丽外担菌（E. gracile）培养液能刺激非寄主植物如萝卜、水稻种子萌发和根生长。赵晨心等[5]检测到引发茶饼病的坏损外担菌（E. vexans）培养液中含有GA3、3-吲哚丁酸（IBA）和6-苄氨基嘌呤（6-BA）等多种植物生长调节物质。……