Penicillium crustosum Thom. is a fungus commonly found on cheese and nuts, but is also a postharvest pathogen that causes blue mold disease of pome and stone fruits including plum and nectarine (Louw and Korsten 2016; Restuccia et al. 2006). The fungus produces mycotoxins (penitrem A, roquefortine C, terrestric acid, and cyclopenol) which are of concern for human health (Frisvad and Samson 2004). In Serbia, P. crustosum has been previously described on apple fruit (Vico et al. 2014). On nectarine fruit (Prunus persica var. nucipersica), after 6 weeks of cold storage, symptoms of blue mold developed in a fruit market in Belgrade, Serbia. The fruit was collected and isolations performed in November 2017. Decayed areas on infected fruit were soft, light to medium brown with blue-green sporulation on the fruit surface. Two isolates were obtained (N2AS and N2BS) and cultured on Czapek yeast autolysate agar (CYA), malt extract agar (MEA), yeast extract sucrose agar (YES) and potato dextrose agar (PDA) at 25°C for 7 days. Isolates were identified as P. crustosum based on morphological features (Frisvad and Samson 2004; Pitt and Hocking 2009). On all media, mycelia were white and colonies turned blue-green with abundant sporulation. Colonies of both isolates were radially sulcate on MEA and YES, and plane with a granular texture on CYA and PDA, and were yellow to orange on the reverse side on YES. Mean colony diameter on PDA was 29.2 ± 1.2 mm for N2AS, and 31.3 ± 1.4 mm for N2BS; on CYA 30.8 ± 1.2 mm for N2AS and 30.9 ± 1.1 mm for N2BS; on YES 40.7 ± 3.6 mm for N2AS and 43.6 ± 1.4 mm for N2BS; and on MEA 33.4 ± 1.2 mm for N2AS and 34 ± 2.5 mm for N2BS. Crusts of conidial masses formed on MEA and PDA after 10 days. Conidiophores of both isolates were terverticillate, stipes were septate with rough walls, and conidia, borne in columns, were smooth and spherical to subglobose. Conidial diameter for N2AS was 2.32 to 3.95 (average 3.13) µm and for N2BS was 2.34 to 3.98 (average 3.27) µm (n=50). Isolates formed a yellow ring, using Ehrlich's reagent, indicating lack of cyclopiazonic acid, but production of other alkaloids. Morphological identification was confirmed by isolating genomic DNA, PCR amplification of the partial β-tubulin gene using Bt2a/Bt2b (Glass and Donaldson 1995) and sequencing. BLAST analysis revealed that N2AS sequence (MT799805) was 99% similar and N2BS (MT799806) was identical to sequences AY674351 (strain CBS 101025) and KJ775121 (strain DTO_244H8) of P. crustosum in GenBank. Sequences (2X consensus) of the two isolates differed in one nucleotide showing the existence of single-nucleotide polymorphism among P. crustosum isolates. Pathogenicity was tested on nectarine, peach and apple fruit (four fruit per isolate and the control). Fruit were washed, surface-sanitized with 70% ethanol, and wound (10x4 mm) inoculated on two sides with 40 μl of a 105/ml conidial suspension in sterile distilled water containing 0.1% Tween 20 (TSDW). Control fruit was inoculated with TSDW. Inoculated and control fruit were stored at 25°C for 7 days. Inoculated fruit developed light brown decay with cracks in the epidermis that spread from the inoculation point on nectarines and peaches. Blue-green sporulation was present on all inoculated fruit. Control fruit remained symptomless. The fungus was re-isolated and was morphologically identical to the original isolates, thus completing Koch's postulates. This is the first report of P. crustosum causing postharvest blue mold decay on nectarine fruit in Serbia. Results show that P. crustosum is not only present as a postharvest pathogen of apple fruit, but of nectarine as well and may pose a threat in storage of both pome and stone fruits in Serbia. References: Frisvad, J. C. and Samson, R. A. 2004. Stud. Mycol. 49:1. Glass, N.L. and Donaldson, G. C. 1995. Appl. Environ. Microbiol. 61: 1323. Louw, J.P., and Korsten, L. 2016. Eur. J. Plant Pathol. 146: 779. Pitt, J. I. and Hocking, A. D. 2009. Fungi and food spoilage, 239. Springer. Restuccia et al. 2006. J. Food Prot. 69: 2465. Vico, I., et al. 2014. Plant Dis. 98:1430. Acknowledgment: This research was supported by the project III46008, No. 451-03-68/2020-14/200116, financed by the Ministry of Education, Science and Technological Development, Republic of Serbia.

中文翻译：

---

塞尔维亚青霉菌对油桃果实造成蓝霉病的首次报道。

青霉Thom。是一种常见于奶酪和坚果上的真菌，但也是一种采后病原体，会引起包括李子和油桃在内的石榴和核果的蓝霉病（Louw and Korsten 2016; Restuccia et al。2006）。真菌产生霉菌毒素（青霉菌素A，罗克福汀C，terrestric酸和环戊醇），这对人体健康至关重要（Frisvad和Samson 2004）。在塞尔维亚，以前已经在苹果果实上描述了硬皮假单胞菌（Vico等人，2014）。在油桃果实（Prunus persica var。nucipersica）上，冷藏6周后，塞尔维亚贝尔格莱德的水果市场出现了蓝色霉菌的症状。收集了果实并于2017年11月进行了分离。被感染果实的腐烂区域柔软，浅棕色至中等棕色，果实表面有蓝绿色的孢子形成。获得两个分离物（N2AS和N2BS），并在Czapek酵母自溶琼脂（CYA），麦芽提取物琼脂（MEA），酵母提取物蔗糖琼脂（YES）和马铃薯葡萄糖琼脂（PDA）上于25°C培养7天。根据形态学特征，分离株被鉴定为十字杆菌（Frisvad和Samson 2004； Pitt和Hocking 2009）。在所有培养基上，菌丝都是白色的，菌落变成蓝绿色，具有丰富的孢子形成。两种分离物的菌落均在MEA和YES上呈放射状形成，并在CYA和PDA上呈颗粒状分布，在YES上呈黄色至橙色。PDA上的平均菌落直径对于N2AS是29.2±1.2 mm，对于N2BS是31.3±1.4 mm；对于N2AS，在CYA上为30.8±1.2毫米;对于N2BS，为30.9±1.1毫米; 是的，对于N2AS为40.7±3.6毫米，对于N2BS为43.6±1.4毫米; 在MEA上，N2AS为33.4±1.2 mm，N2BS为34±2.5 mm。10天后，MEA和PDA上形成了分生孢子团。两种分离物的分生孢子都为土生孢子状，柄的壁为粗糙的壁，并且分生于圆柱中的分生孢子是光滑的，球形至近球形。N2AS的分生孢子直径为2.32至3.95（平均3.13）μm，N2BS的分生孢子直径为2.34至3.98（平均3.27）μm（n = 50）。分离物使用Ehrlich试剂形成黄色环，表明缺少环吡唑酸，但产生其他生物碱。通过分离基因组DNA，使用Bt2a / Bt2b对部分β-微管蛋白基因进行PCR扩增（Glass and Donaldson 1995）和测序来确认形态学鉴定。BLAST分析显示，N2AS序列（MT799805）与99.％相似，并且N2BS（MT799806）与GenBank中的克鲁氏假单胞菌的序列AY674351（菌株CBS 101025）和KJ775121（菌株DTO_244H8）相同。两种分离物的序列（2X共有序列）在一个核苷酸上有所不同，表明在克鲁氏假单胞菌分离物中存在单核苷酸多态性。测试了油桃，桃和苹果果实的致病性（每个分离株和对照果实四个果实）。清洗水果，用70％乙醇表面消毒，然后在伤口（10x4毫米）的两侧接种40μl的105 / ml分生孢子悬液在含有0.1％Tween 20（TSDW）的无菌蒸馏水中。用TSDW接种对照果实。接种和对照的果实在25°C下保存7天。接种的果实会出现浅棕色的腐烂，表皮中的裂纹从油桃和桃的接种点开始扩散。所有接种的水果均出现蓝绿色芽孢。对照果实无症状。重新分离真菌，并在形态上与原始分离物相同，从而完成了科赫的假设。这是关于克鲁维酵母造成塞尔维亚油桃果实采后蓝霉变的首次报道。结果表明，克鲁氏假单胞菌不仅作为苹果果实的采后病原体，而且还作为油桃的病原体，并且可能对塞尔维亚的石榴和核果的贮藏构成威胁。参考文献：Frisvad，JC和Samson，RA 2004。Mycol。49：1 NL，Glass和GC，Donaldson，1995年。环境。微生物。61：1323. Louw，JP和Korsten，L. 2016.欧元。J.植物病理学。146：779。Pitt，JI和Hocking，公元2009年。真菌和食物变质，239。Springer。Restuccia等。2006年。食品杂志。69：2465。Vico，I。等人。2014。植物病。98：1430。致谢：