First Report of Pomegranate Fruit Rot Caused by Botryosphaeria dothidea in Anhui Province of China

During the summer of 2010, unfamiliar symptoms of fruit rot were frequently observed on different Tunisian olive (Olea europaea) cultivars. These symptoms appeared to be associated with the damage caused by the olive fruit fly (Bactrocera oleae). At first, infected olives showed a brown color and then fruits begin to depress until they become completely mummified and fall immaturely. This problem was more pronounced on table olive cultivars (Ascolana, Meski, and Picholine) in the northern Tunisian regions (Nabeul), with an infection incidence of 65%. Infected Ascolana olives were disinfected with 70% ethanol for 2 min, rinsed in sterile distilled water, and air dried. Several pieces were cut and placed on acidified (2.5 ml of a 25% [vol/vol] solution of lactic acid per liter of medium) potato dextrose agar medium (PDA). All plates were incubated at 25°C for 4 days under continuous fluorescent light. A fast-growing fungus with an abundant, aerial mycelium, which was gradually veering from white to dark gray, was constantly isolated. On the reverse side of the colonies, an olive green coloration spread to the edge and became darker from the center until the underside was completely black. Conidia produced on the PDA plate were hyaline, single or double cell, ellipsoid, with a subobtuse apex and a truncate base, and averaged 22.70 × 5.32 μm. Conidiophores were hyaline, cylindrical, smooth, branched at the base, with an average of 14 to 24 × 2 to 3 μm. Pathogenicity of an isolate was conducted by dipping 20 olives wounded by a sterilized scalpel in a conidial suspension (105 conidia/ml), covering inoculated olives with moisture filter paper, and incubating them in a polyethylene bag under darkness at 25°C. Controls however, were wounded and dipped in sterile distillated water. Seven days after the inoculation, olives showed a brown color covering half of the fruit. Later (15 days after), this browning was accentuated and several black pycnidia were observed. Forty days after inoculation, fruits were completely dried out and the kernel was already appearing. Controls, however, remained totally healthy. Koch's postulates was then verified and showed that pure cultures were obtained after reisolations from inoculated olives, whereas the controls were free of the fungus. BLAST analysis of the internal transcribed spacer region (ITS) of rDNA of one isolate showed 99% identity with the ITS sequence of Botryosphaeria dothidea (GenBank Accession No. FM955381.1). Species of the family of Botryosphaeriaceae are common pathogens causing fruit rot and dieback of many woody plants (3). Drupe rot problem caused by B. dothidea was reported on olives in Greece (4) and southern Italy (2). It was reported that the fungus invades the drupes through the wounds caused by the olive fruit fly and may even be transmitted by it (1), and recently Moral et al. (3) suggested that the olive fruit fly is essential for the initiation of the disease on the fruit. To our knowledge, this is the first report of fruit rot of olives caused by B. dothidea in Tunisia. References: (1) N. González et al. Bol. San. Veg. Plagas 32:709, 2006. (2) C. Lazzizera et al. Plant Pathol. 57:948, 2008. (3) J. Moral et al. Phytopathology 100:1340, 2010. (4) A. J. L Phillips et al. Mycopathology 159:433, 2005.

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First report of Botryosphaeria dothidea causing dieback of Vatica mangachapoi in Anhui Province of China

Journal of Plant Pathology ◽

10.1007/s42161-019-00288-5 ◽

2019 ◽

Vol 101 (4) ◽

pp. 1231-1232

Author(s):

Xue Yang ◽

Yong-Jie Qi ◽

Chun-Yan Gu ◽

Hao-Yu Zang ◽

Yu Chen

Keyword(s):

Anhui Province ◽

Botryosphaeria Dothidea ◽

First Report

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First Report of Penicillium glabrum Causing Fruit Rot of Pomegranate (Punica granatum) in Greece

Plant Disease ◽

10.1094/pdis-93-12-1347a ◽

2009 ◽

Vol 93 (12) ◽

pp. 1347-1347 ◽

Cited By ~ 13

Author(s):

G. A. Bardas ◽

G. D. Tzelepis ◽

L. Lotos ◽

G. S. Karaoglanidis

Keyword(s):

Its Region ◽

Punica Granatum ◽

Fruit Rot ◽

Academic Press ◽

First Report ◽

Morphological Criteria ◽

Diseased Fruit ◽

Internal Fruit Rot ◽

Dna 2 ◽

Pomegranate Fruit

During September and October of 2008 in the region of Larisa (central Greece), postharvest fruit rot was observed on pomegranate (cv. Kapmaditika), which is rapidly increasing in production in Greece, causing losses of 10 to 20% after 2 months of cold storage (5 to 6°C). Infected fruits showed green conidiophores in the calyx area, while internal symptoms consisted of soft, brown tissue that became covered with green mycelium and conidiophores. To isolate the casual agent, conidia and conidiophores were scraped aseptically from the internal fruit rot, suspended in sterile water, and streaked onto potato dextrose agar (PDA). Single hyphal tips were then transferred to new PDA plates. A fungus consistently isolated from the infected tissues was identified as Penicillium glabrum (Wehmer) Westling on the basis of morphological criteria, with conidiophores smooth or finely roughened and conidia in compact columns, glubose to subglubose, approximately 3.0 μm, with walls somewhat echinulate (1). The identification was confirmed by sequencing the internal transcribed spacer (ITS) region spanning ITS1, 5.8S, and ITS2 of the ribosomal DNA (2). The nucleotide sequence was submitted to GenBank (Accession No. FN313540). The pathogenicity of the isolated fungus was tested on five mature pomegranate fruit (cv. Kampaditika) after being surface sterilized with 5% sodium hypochlorite. A plug (5 mm in diameter) obtained from the margins of a P. glabrum colony was transferred to wounds (3 × 3 mm) made with a scalpel in the surface of fruit. Fruit inoculated with sterile PDA plugs served as controls. Fruit were incubated at 22°C and 80% relative humidity in the dark. Extensive decay, similar to that observed on diseased fruit in the field, was observed on the inoculated fruit 7 days after inoculation, whereas control fruit showed no decay. The pathogen was reisolated from inoculated fruit but not from the noninoculated fruit. To our knowledge, this is the first report of P. glabrum causing postharvest fruit rot of pomegranates in Greece. References: (1) C. Thom and K. B. Raper. Page 176 in: A Manual of the Penicillia. Williams and Wilkins, Baltimore, 1949. (2) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, 1990.

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First Report of Fruit Rot in Pear Caused by Botryosphaeria dothidea in Italy

Plant Disease ◽

10.1094/pdis-02-12-0130-pdn ◽

2012 ◽

Vol 96 (6) ◽

pp. 910-910 ◽

Cited By ~ 9

Author(s):

A. Garibaldi ◽

D. Bertetti ◽

A. Poli ◽

M. L. Gullino

Keyword(s):

Morphological Characteristics ◽

Its Region ◽

The United States ◽

Fruit Rot ◽

Pathogenicity Test ◽

Botryosphaeria Dothidea ◽

First Report ◽

Irregular Margin ◽

Pyrus Communis L ◽

Pathogenicity Tests

Pear (Pyrus communis L.) is widely grown in Italy, the leading producer in Europe. In summer 2011, a previously unknown rot was observed on fruit of an old cultivar, Spadoncina, in a garden in Torino Province (northern Italy). The decayed area of the fruit was soft, dark brown, slightly sunken, circular, and surrounded by an irregular margin. The internal decayed area appeared rotten and brown and rotted fruit eventually fell. To isolate the causal agent, fruits were soaked in 1% NaOCl for 30 s and fragments (approximately 2 mm) were taken from the margin of the internal diseased tissues, cultured on potato dextrose agar (PDA), and incubated at temperatures between 20 and 28°C under alternating light and darkness. Colonies of the fungus initially appeared whitish, then turned dark gray. After about 30 days of growth, unicellular elliptical hyaline conidia were produced in pycnidia. Conidia measured 16 to 24 × 5 to 7 (average 20.1 × 5.7) μm (n = 50). The morphological characteristics are similar to those of the fungus Botryosphaeria dothidea (Moug.: Fr.) Ces. & De Not. (4). The internal transcribed spacer (ITS) region of rDNA was amplified with the primers ITS1/ITS4 and sequenced. BLAST analysis (1) of the 473-bp segment showed a 100% similarity with the sequence of the epitype of B. dothidea AY236949. The nucleotide sequence has been assigned the GenBank Accession No. JQ418493. Pathogenicity tests were performed by inoculating six pear fruits of the same cultivar (Spadoncina) after surface disinfesting in 1% sodium hypochlorite and wounding. Mycelial disks (8 mm diameter), obtained from 10-day-old PDA cultures of one strain, were placed on wounds. Six control fruits were inoculated with plain PDA. Fruits were incubated at 25 ± 1°C in plastic boxes. The first symptoms developed 3 days after inoculation. After 5 days, the rot was very evident and B. dothidea was consistently reisolated. Noninoculated fruits remained healthy. The pathogenicity test was performed twice. B. dothidea was identified on decayed pears in the United States (2), South Africa, New Zealand, Japan, and Taiwan (3). To our knowledge, this is the first report of the presence of B. dothidea on pear in Italy, as well as in Europe. In Italy, the economic importance of the disease on pear fruit is at present limited, although the pathogen could represent a risk for this crop. References: (1) S. F. Altschul et al. Nucleic Acids Res., 25:3389, 1997. (2) L. F. Grand. Agr. Res. Serv. Techn. Bull. 240:1, 1985. (3) Y. Ko et al. Plant Prot. Bull. (Taiwan) 35:211, 1993. (4) B. Slippers et al. Mycologia 96:83, 2004.

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First Report of Botryosphaeria dothidea Causing Fruit Rot of Plum in Spain

Plant Disease ◽

10.1094/pdis-08-12-0709-pdn ◽

2013 ◽

Vol 97 (4) ◽

pp. 556-556 ◽

Cited By ~ 2

Author(s):

L. F. Roca ◽

M. C. Raya ◽

A. Trapero

Keyword(s):

Relative Humidity ◽

Its Region ◽

Southern Spain ◽

Stone Fruit ◽

Fruit Rot ◽

Tween 20 ◽

Botryosphaeria Dothidea ◽

First Report ◽

Leaf Spots ◽

Morphological Criteria

Species in the Botryosphaeriaceae are known to produce cankers, dieback, blights, and leaf spots on many hosts, mainly under stress conditions. Several Botryosphaeria spp. may also cause pre- or post-harvest decay of stone fruit, such as peaches (2). In June 2012, fruit of plum (Prunus domestica cv. Golden Japan) showing soft, brown, and slightly sunken necrotic lesions were observed in several orchards affected by hail in Cordoba province (southern Spain). Symptomatic fruit were collected and incubated at 25°C and 100% relative humidity. Isolations were done on potato dextrose agar (PDA). Mycelium and black pycnidia developed on the surface of incubated fruit and on PDA plates. Conidia were hyaline, aseptate, and fusoid. According to morphological criteria, the fungus was identified as Fusicoccum aesculi, the anamorph of Botryosphaeria dothidea (3). The internal transcribed spacer (ITS) region of rDNA was amplified with primers ITS4/ITS5 and sequenced. BLAST analysis of the 528-bp fragment showed 100% homology with the sequence of B. dothidea. Pathogenicity tests were performed on immature healthy fruit (2 weeks before harvest) of the same cultivar from the same orchards. Fruit were washed in deionized water with Tween 20 (Polyoxyethylene 20 sorbitan monolaureate 99%, 0.1 ml/liter) and surface sterilized in 10% sodium hypochlorite for 1 min. Twenty-four fruit were inoculated using mycelial-agar discs. Twelve fruit were previously wounded with a sterile 0.5-mm-diameter needle. The same number of fruit, wounded and unwounded, served as a control. All fruit were incubated at 25°C and 100% relative humidity. Seven days after inoculation, 83% of wounded inoculated fruit showed rot symptoms. After 9 days, fruit rot symptoms started to appear on unwounded inoculated fruit. Twenty days after inoculation, 100% of wounded and unwounded fruit showed rot symptoms that led to mummification of the fruit. Pycnidia developed on inoculated fruit and the fungus was reisolated. No symptoms developed on control fruit. These results demonstrate that B. dothidea is pathogenic on plum and that wounds favor infection, although they are not needed. To our knowledge this is the first report of B. dothidea causing fruit rot of plum in Spain. This pathogen is well known in southern Spain causing a serious fruit rot of olive (1) and could have a great impact on plum production in this region, especially when there is damage to the fruits as occurred this year with hail. References: (1) J. Moral et al. Phytopathology 100:1340, 2010. (2) J. M. Ogawa et al. Compendium of Stone Fruit Diseases. APS Press, St. Paul, MN, 1995. (3) B. Slippers et al. Mycologia 96:83, 2004.

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