Uromycladium acaciae has caused an epidemic of wattle rust on Acacia mearnsii in southern Africa since 2013. In April 2016, conidiomata of a species of Sphaerellopsis were observed parasitizing telia of U. acaciae on foliar samples collected from three plantations in Mpumalanga, South Africa. An isolate was identified as Sphaerellopsis macroconidialis based on a phylogenetic species hypothesis of the internal transcribed spacer (ITS) region. This is the first report of this species of mycoparasite from South Africa and on this host. To investigate the seasonal population dynamics of this mycoparasite, the presence of Sphaerellopsis on telia of U. acaciae was assessed monthly between May 2016 and April 2017. The proportion of samples with conidiomata of Sphaerellopsis was greatest between May and November. This period is outside both the peak growing season for A. mearnsii and the main epidemic period for U. acaciae. Results suggest that Sphaerellopsis may have little impact on U. acaciae during epidemic periods of the year but could reduce the over-wintering survival of this damaging rust fungus and lower initial inoculum loads at the start of the following growth season.

中文翻译：

---

Sphaerellopsis macroconidialis 的过度寄生可能会降低 Uromycladium acaciae 的越冬存活率

Uromycladium acaciae造成对荆生锈的流行相思 荆自2013年在2016年4月在南部非洲，一个物种的分生孢子Sphaerellopsis人的观察寄生于商Telia ü。 从南非普马兰加省的三个种植园收集的叶面样品上的金合欢。根据内部转录间隔区 (ITS) 区域的系统发育物种假设，分离株被鉴定为Sphaerellopsis macroconidialis。这是来自南非和该宿主的这种真菌寄生虫的第一份报告。为了研究这种真菌的季节性种群动态，在U的telia上存在球孢属. 2016 年 5 月至 2017 年 4 月期间，每月对acaciae进行评估。5月至 11 月期间，球藻分生孢子的样本比例最大。这个时期是A 的两个生长高峰期之外。 mearnsii和U的主要流行期。 相思树。结果表明球藻可能对U几乎没有影响。 在一年中的流行期间，金合欢会减少这种破坏性锈菌的越冬存活率，并在下一个生长季节开始时降低初始接种量。