Biology Research Division, Ganoderma and Diseases Research for Oil Palm (GanoDROP) Unit, Malaysian Palm Oil Board, 6 Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Selangor, Malaysia.
Plant Protection Department, Faculty of Agriculture, Universiti Putra Malaysia, 43400, Serdang, Malaysia.
World J Microbiol Biotechnol. 2017 Dec 18;34(1):15. doi: 10.1007/s11274-017-2396-1.
Ganoderma boninense, the main causal agent of oil palm (Elaeis guineensis) basal stem rot (BSR), severely reduces oil palm yields around the world. To reduce reliance on fungicide applications to control BSR, we are investigating the efficacy of alternative control methods, such as the application of biological control agents. In this study, we used four Streptomyces-like actinomycetes (isolates AGA43, AGA48, AGA347 and AGA506) that had been isolated from the oil palm rhizosphere and screened for antagonism towards G. boninense in a previous study. The aim of this study was to characterize these four isolates and then to assess their ability to suppress BSR in oil palm seedlings when applied individually to the soil in a vermiculite powder formulation. Analysis of partial 16S rRNA gene sequences (512 bp) revealed that the isolates exhibited a very high level of sequence similarity (> 98%) with GenBank reference sequences. Isolates AGA347 and AGA506 showed 99% similarity with Streptomyces hygroscopicus subsp. hygroscopicus and Streptomyces ahygroscopicus, respectively. Isolates AGA43 and AGA48 also belonged to the Streptomyces genus. The most effective formulation, AGA347, reduced BSR in seedlings by 73.1%. Formulations using the known antifungal producer Streptomyces noursei, AGA043, AGA048 or AGA506 reduced BSR by 47.4, 30.1, 54.8 and 44.1%, respectively. This glasshouse trial indicates that these Streptomyces spp. show promise as potential biological control agents against Ganoderma in oil palm. Further investigations are needed to determine the mechanism of antagonism and to increase the shelf life of Streptomyces formulations.
被孢霉（Ganoderma boninense）是导致油棕（Elaeis guineensis）基部腐烂病（BSR）的主要病原体，它严重降低了世界各地油棕的产量。为了减少对杀菌剂控制 BSR 的依赖，我们正在研究替代控制方法的有效性，例如应用生物防治剂。在这项研究中，我们使用了从油棕根际分离出的四种链霉菌样放线菌（分离株 AGA43、AGA48、AGA347 和 AGA506），并在之前的研究中筛选了它们对被孢霉的拮抗作用。本研究的目的是对这四种分离株进行特征描述，然后评估它们单独应用于土壤中的腐殖质粉配方时抑制油棕幼苗 BSR 的能力。部分 16S rRNA 基因序列（512 bp）分析表明，这些分离株与 GenBank 参考序列具有非常高的序列相似性（>98%）。分离株 AGA347 和 AGA506 与吸水链霉菌亚种 hygroscopicus 和吸水链霉菌 ahygroscopicus 的相似性分别为 99%。分离株 AGA43 和 AGA48 也属于链霉菌属。最有效的配方 AGA347 将幼苗的 BSR 降低了 73.1%。使用已知抗真菌剂生产菌链霉菌诺尔斯氏菌（Streptomyces noursei）的 AGA043、AGA048 或 AGA506 的配方将 BSR 降低了 47.4%、30.1%、54.8%和 44.1%。该温室试验表明，这些链霉菌属具有作为油棕被孢霉潜在生物防治剂的潜力。需要进一步研究以确定拮抗作用的机制并延长链霉菌配方的保质期。
