Biocontrol of black scurf on potato by seed tuber treatment with Pythium oligandrum
Biocontrol of black scurf on potato by seed tuber treatment with Pythium oligandrum
复制标题
DOI：
10.1016/j.biocontrol.2011.10.016
复制
发表时间：
2012-03-01
影响因子：
4.2
通讯作者：
Takenaka, Shigehito
中科院分区：
文献类型：
--
作者：
Ikeda, Sachiko;Shimizu, Ayano;Takenaka, Shigehito
采用田间试验方法，研究了寡雄腐霉对马铃薯黑星病的防治效果。将感染黑色皮屑菌核的种薯在10（3）、10（4）或10（5）mL（-1）寡雄假单胞菌卵孢子的悬浮液中浸渍几秒钟，然后风干。各处理水平均显著降低了匍匐茎的发病率，其水平与化学防治相似。当测定粘附于种薯表面的寡雄假单胞菌种群时，用10（4）或10（5）个卵孢子mL（-1）处理的种薯上的卵孢子计数在刚浸渍后分别为约540/cm（2）或约22，000/cm（2），并且在3周孵育后分别降低至约170/cm（2）或2900/cm（2）。激光共聚焦扫描显微镜观察和免疫酶染色表明，寡雄假单胞菌菌丝已在菌核上定殖，并通过盘绕在菌核周围建立了紧密的接触。茄属菌丝以类似于双重培养试验中观察到的方式存在于种薯表面。R的定量。solani DNA的PCR检测结果表明，该菌为R.与未处理的块茎相比，用寡雄假单胞菌处理的种子块茎上的茄病菌种群减少。此外，使用马铃薯块茎圆盘测定法测定寡雄假单胞菌诱导对黑星病的抗性的能力。用寡雄假单胞菌的细胞壁蛋白组分处理块茎圆片增强了防御相关基因如3-脱氧-D-阿拉伯庚酮糖酸7-磷酸合酶、脂氧合酶和碱性PR-6基因的表达，并降低了用R.与未处理的对照相比。这些结果表明，少雄拟单胞菌对黑星病的生防机制涉及真菌寄生和诱导抗性。(C)2011 Elsevier Inc. All rights reserved.
The biological control activity of Pythium oligandrum against black scurf of potato caused by Rhizoctonia solani AG-3 was evaluated in field experiments after treatment of potato seed tubers with P. oligandrum. Seed tubers infected with black scurf sclerotia were dipped for a few seconds in a suspension of 10(3), 10(4) or 10(5) mL(-1) P. oligandrum oospores and were then air-dried. Each level of P. oligandrum-treatment significantly reduced the disease rates of stolon at a level similar to that achieved by chemical control. When P. oligandrum populations adherent to the surface of seed tubers were determined, oospore counts on tubers treated with 10(4) or 10(5) oospores mL(-1) were about 540/cm(2) or about 22,000/cm(2) just after dipping and decreased to about 170/cm(2) or 2900/cm(2) after a 3-week incubation, respectively. Confocal laser scanning microscopic observation with an immuno-enzymatic staining procedure showed that P. oligandrum hyphae had colonized the sclerotia and established close contact by coiling around the R. solani hyphae present on the surface of seed tubers, in a manner similar to that observed in the dual-culture test. Quantification of R. solani DNA by PCR indicated that the R. solani population was reduced on the seed tubers treated with P. oligandrum compared to untreated tubers. Furthermore, the ability of P. oligandrum to induce resistance against black scurf was determined using a potato tuber disk assay. Treatment of tuber disks with the cell wall protein fraction of P. oligandrum enhanced the expression of defense-related genes such as 3-deoxy-D-arabino-heptulosonate 7-phosphate synthase, lipoxygenase and basic PR-6 genes, and reduced disease severity upon challenge with R. solani compared with untreated controls. These results suggest that biocontrol mechanisms employed by P. oligandrum against black scurf involve both mycoparasitism and induced resistance. (C) 2011 Elsevier Inc. All rights reserved.