Abstract

A strain of Kalmusia variispora associated with grapevine trunk diseases (GTDs) was identified in Iran and induced disease symptoms on the host in greenhouse conditions. The grapevine pathogens are able to produce a plethora of toxic metabolites belonging to different classes of naturally occurring compounds. Two homogeneous compounds were isolated from the organic extract of K. variispora culture filtrates. They were identified by physic (specific optical rotation), and spectroscopic (essentially 1D ¹H and ¹³C NMR and HR ESIMS) methods as the fungal polyketides massarilactones D and H (1 and 2). The unassigned absolute configuration of massarilactone D was unambiguously determined by X-ray diffractometric analysis. Massarilactones D and H showed phytotoxic activity on Vitis vinifera L. at two concentrations used and depending from the days of inoculation. Phytotoxicity is also increased when the 3,4,7-O,O',O"-triacetyl derivative of massarilactone D (3) was assayed on the host plant. This is the first report on the investigation of phytotoxic metabolites produced by K. variispora isolated from infected grapevine in Iran and they seem to be involved in the development of disease symptoms.

摘要

在伊朗发现了一种与葡萄树干病 ( GTD)相关的Kalmusia variispora菌株，并在温室条件下在宿主身上诱发了疾病症状。葡萄藤病原体能够产生大量属于不同类别的天然化合物的有毒代谢物。从K. variispora培养物滤液的有机提取物中分离出两种均质化合物。它们通过物理（比旋光度）和光谱（基本上是 1D ¹ H 和¹³ C NMR 和 HR ESIMS）方法被鉴定为真菌聚酮类马萨里内酯 D 和 H（1和2）。通过 X 射线衍射分析明确确定了马萨里内酯 D 的未分配绝对构型。Massarilactones D 和 H在两种使用浓度下对Vitis vinifera L.显示出植物毒性活性，这取决于接种天数。在寄主植物上测定马萨里内酯 D ( 3 )的 3,4,7- O,O',O"-三乙酰衍生物时，植物毒性也增加。这是关于由K.产生的植物毒性代谢物研究的第一份报告。从伊朗受感染的葡萄藤中分离出的变异孢子菌，它们似乎与疾病症状的发展有关。