环链虫草Cordyceps cateniannulata对番茄生长和抗氧化酶活性的影响

Effect of Cordyceps cateniannulata on the growth and antioxidant enzyme activity of Solanum lycopersicum

摘要:

【目的】评估环链虫草Cordyceps cateniannulata对植物促生和植物抗氧化酶活性的影响。【方法】本研究利用浸种法将环链虫草接种于番茄植物体，在接种后的第30天和60天，通过番茄株高、根长、地上和地下部分的干鲜重指标评价其对番茄生长的影响；在接种后第10、20、30、60和90天，通过选择性培养基分析其在番茄不同组织中的生存情况，使用形态学及DNA序列比对的方法检验所分离菌株与原有菌株的一致性。在处理后的第30天，检测番茄叶片中的过氧化物酶（POD）、过氧化氢酶（CAT）、超氧化物歧化酶（SOD）及丙二醛（MDA）含量，观察环链虫草对番茄的抗氧化酶活性影响。【结果】环链虫草可定殖于番茄幼苗且对番茄生长有显著促进作用，菌株对植株的定殖偏好性分别为根部>茎部>叶部。酶活检测结果表明，处理组番茄叶片防御酶活性均呈显著升高的趋势，其中POD、CAT、SOD活性分别比对照增加了52.21%、75.31%和158.59%，MDA含量下降了35.15%。【结论】环链虫草可以通过浸种的方法感染并定殖番茄幼苗的根、茎、叶，促进番茄幼苗的生长并提高番茄抗氧化酶活性，具有较好的田间生态应用潜力。

关键词:番茄;环链虫草;促生作用;抗氧化酶活性

Abstract:

[Objective] This paper aims to evaluate the effect of Cordyceps cateniannulata on the growth and antioxidant enzyme activity of Solanum lycopersicum.[Methods] With the seed soaking method, S. lycopersicum was inoculated with C. cateniannulata. The plant height, root length, fresh and dry weight of root, and fresh and dry weight of shoot of S. lycopersicum were measured 30 and 60 days post inoculation (dpi) to assess the influence of the fungus on plant growth. Endophytic colonization of different plant parts by the tested fungus was confirmed 10, 20, 30, 60 and 90 dpi via a selective medium. Through morphological identification and DNA sequence alignment, we tested whether the endophytes isolated from S. lycopersicum were the inoculated strains. The content of peroxidase (POD), catalase (CAT), superoxide dismutase (SOD), and malondialdehyde (MDA) in S. lycopersicum leaves was determined 30 dpi in a bid to evaluate the effect on antioxidant enzyme activity.[Results] C. cateniannulata colonized S. lycopersicum seedlings and promoted the plant growth. At all the five sampling time points, the colonization rate was in the order of root>stem>leaf. C. cateniannulata significantly increased the activity of defense enzymes in S. lycopersicum leaves, as the activity of POD, CAT, and SOD was respectively 52.21%, 75.31%, and 158.59% higher than that of the control and MDA content was 35.15% down from the control.[Conclusion] Through seed inoculation, C. cateniannulata colonizes in roots, stems, and leaves of S. lycopersicum, promoting the seedling growth and enhancing the antioxidant enzyme activity. Thus, this fungus has good application prospects in field.

Key words:Solanum lycopersicum;Cordyceps cateniannulata;growth promotion;antioxidant enzyme activity