Morpho-molecular Identification and Chemical control of Alternaria alternata,causing leaf blight of Gardenia jasminoides Eills in China

Abstract Gardenia jasminoides Eills is a traditional aromatic and medicinal plant that is widely cultivated in China. In 2020, a severe leaf disease on Gardenia was observed in a growing herbal medicine area in Jian County, of Jiangxi Province, China. The causal agent was identified as Alternaria alternata (Fr.) Keissler. by amplification and sequencing the internal transcribed spacer (ITS) region, followed by phylogenetic analysis. Koch's postulates were confirmed by a pathogenicity test conducted with healthy gardenia, including reisolation and identification. To our knowledge, this is the first report of leaf blight caused by Alternaria alternata on Gardenia jasminoides Eills in JiangXi, China. PDA plate bacteriostatic experiment results showed that: Hexaconazole had the best inhibiting effect, which the EC 50 was 14.45 ppm. Therefore, the results are preliminary but promising for future field applications.

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Report of Leaf Blight on Washington Lupine (Lupinus polyphyllus) Caused by Rhizoctonia solani AG 4 in Italy

Plant Disease ◽

10.1094/pdis-93-4-0429a ◽

2009 ◽

Vol 93 (4) ◽

pp. 429-429

Author(s):

A. Garibaldi ◽

G. Gilardi ◽

D. Bertetti ◽

M. L. Gullino

Keyword(s):

Rhizoctonia Solani ◽

Aqueous Suspension ◽

Morphological Characteristics ◽

Its Region ◽

Leaf Blight ◽

Herbaceous Plant ◽

Pathogenicity Test ◽

Lupinus Polyphyllus ◽

Leaf Petiole ◽

Sphagnum Peat

Lupinus polyphyllus (Leguminosae), Washington lupine, is a perennial herbaceous plant. In March 2008, in a campus greenhouse at the University of Torino, Grugliasco (northern Italy), a leaf blight was observed on 20% of potted 30-day-old plants. Semicircular, water-soaked lesions developed on leaves just above the soil line at the leaf-petiole junction and later along the leaf margins. Lesions expanded for several days along the midvein until the entire leaf was destroyed. Blighted leaves turned brown, withered, clung to the shoots, and matted on the surrounding foliage. Severely infected plants died. Plants were grown in a sphagnum peat/perlite/clay (70:20:10) substrate at temperatures between 18 and 25°C and relative humidity of 60 to 80%. Diseased tissue was disinfested for 10 s in 1% NaOCl, rinsed with sterile water, and plated on potato dextrose agar (PDA) amended with 25 mg/liter of streptomycin sulfate. A fungus with the morphological characteristics of Rhizoctonia solani (4) was consistently and readily recovered, then transferred and maintained in pure culture. Ten-day-old mycelium grown on PDA at 20 ± 1°C appeared light brown, rather compact, and exhibited radial growth. The isolates of R. solani successfully anastomosed with tester isolate AG 4 (AG 4 RT 31, obtained from tobacco plants). The hyphal diameter at the point of anastomosis was reduced, the anastomosis point was obvious, and cell death of adjacent cells was observed. Results were consistent with other reports on anastomosis reactions (3). Pairings were also made with tester isolates AG 1, 2.1, 2.2, 3, 6, 7, 11, and BI with no anastomoses observed between the recovered and tester isolates. The internal transcribed spacer (ITS) region of rDNA was amplified using primers ITS4/ITS6 and sequenced. BLASTn analysis (1) of the 660-bp fragment showed 100% homology with the sequence of R. solani. The nucleotide sequence has been assigned GenBank Accession No. FJ486272. For pathogenicity tests, the inoculum of R. solani was prepared by growing the pathogen on PDA for 10 days. Plants of 30-day-old L. polyphyllus were grown in 10-liter containers (10 plants per container) on a steam disinfested sphagnum peat/perlite/clay (70:20:10) medium. Inoculum, consisting of an aqueous suspension of mycelium disks prepared from PDA cultures (5 g of mycelium per plant), was placed at the collar of plants. Plants inoculated with water and PDA fragments alone served as control treatments. Three replicates were used. Plants were maintained in a greenhouse at temperatures between 18 and 23°C. First symptoms, similar to those observed in the nursery, developed 10 days after the artificial inoculation. R. solani was consistently reisolated from infected leaves and stems. Control plants remained healthy. The pathogenicity test was repeated twice. The susceptibility of L. polyphyllus to R. solani was reported in Poland (2). This is, to our knowledge, the first report of leaf blight of L. polyphyllus caused by R. solani in Italy. The importance of the disease is at the moment limited. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) W. Blaszczak. Rocz. Nauk. Roln. Ser A 85:705, 1962. (3) D. E. Carling. Grouping in Rhizoctonia solani by hyphal anastomosis reactions. In: Rhizoctonia Species: Taxonomy, Molecular Biology, Ecology, Pathology and Disease Control. Kluwer Academic Publishers, The Netherlands, 1996. (4) B. Sneh et al. Identification of Rhizoctonia species. The American Phytopathological Society, St Paul, MN, 1991.

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First Report of Taro (Colocasia esculenta) Leaf Blight Caused by Phytophthora colocasiae in Nigeria

Plant Disease ◽

10.1094/pdis-12-10-0890 ◽

2011 ◽

Vol 95 (5) ◽

pp. 618-618 ◽

Cited By ~ 11

Author(s):

R. Bandyopadhyay ◽

K. Sharma ◽

T. J. Onyeka ◽

A. Aregbesola ◽

P. Lava Kumar

Keyword(s):

Crop Protection ◽

Central Africa ◽

Morphological Characteristics ◽

Its Region ◽

Selective Medium ◽

Colocasia Esculenta ◽

Leaf Blight ◽

Pathogenicity Test ◽

Phytophthora Colocasiae ◽

Detached Leaves

In November 2009, many farmers in Abia State were alarmed by complete destruction of their taro (Colocasia esculenta (L.) Schott.) crop. Symptoms, suggestive of leaf blight caused by Phytophthora colocasiae Raciborski (2), began as small, brown, water-soaked lesions that rapidly enlarged to form large, dark brown, coalescing lesions, sometimes with orange host exudations. White sporulation was evident on the lesion surface under wet conditions. The pathogen caused rapid defoliation and killed plants. The epidemic was widespread in 2010 during the rainy season (April to November) in all taro-growing areas of Nigeria. Diseased leaves were collected from taro in Iwo Village near Ibadan, cut into 4-cm2 pieces, washed in several changes of sterile water, and incubated in petri dishes lined with wet filter paper at 22°C. Newly produced sporangia were collected from the incubated leaves and plated on a selective medium (1). Sporangia were hyaline, papillate, and measured 25 to 55 × 15 to 30 μm. Zoospores encysted within 30 min after release; cysts were 9.7 to 19.5 μm in diameter. Sporangia and zoospore formation were induced in water and by chilling, respectively (1). Two leaves each of three 1-month-old taro and three Xanthosoma plants (both unknown clones) and six detached leaves of taro were inoculated with a 1 × 105/ml zoospore suspension of isolates PC01 and PC02. Detached leaves were incubated in moist chambers at 22°C. Plants were covered with polyethylene bags for 12 h after inoculation and maintained in a screenhouse. Water-soaked lesions appeared on detached leaves within 24 h postinoculation and the leaves were completely rotted 48 h later. All inoculated attached leaves of taro, but not Xanthosoma, showed typical leaf blight symptoms including abundant sporangial production. Noninoculated control detached leaves and plants were disease free. Sporangia from detached and attached inoculated leaves, when plated on selective medium, produced typical P. colocasiae colonies. The internal transcribed spacer (ITS) region of rDNA was amplified using the ITS1 and ITS4 primers (3). Amplicons (786 bp) were sequenced in both directions and submitted to GenBank (Accession Nos. HQ602756, HQ602757, HQ602758, and HQ602759). A BLASTn search revealed 99% similarity to a P. colocasiae strain of the Pacific Region (Accession No. GU111604), but only 94% similarity to a P. colocasiae strain from India (Accession No. GQ202149). The sequence analysis, morphological characteristics, and pathogenicity test confirmed the taro leaf blight pathogen as P. colocasiae. There are previous reports of occurrence of taro blight-like disease attributed to P. colocasiae in Ethiopia, Equatorial Guinea (1), and more recently in Cameroon, but comprehensive details on pathogen or disease are not available. To our knowledge, this is the first confirmed record in Nigeria of P. colocasiae causing taro blight. This disease poses a serious threat to the production and biodiversity of this important food crop. Urgent interventions are necessary to halt this emerging epidemic in West and Central Africa. References: (1) Phytophthora colocasiae, In: CABI-Crop Protection Compendium. CAB International, Wallingford, UK, 2005. (2) P. S. Tsao. Page 219 in: Phytophthora: Its Biology, Taxonomy, Ecology and Pathology. The American Phytopathological Society. St. Paul, MN, 1983. (3) T. J. White et al. Page 315 in: PCR Protocol: A Guide to Methods and Applications. Academic Press, London. 1990.

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First Report of Leaf Blight on Woodland Sage Caused by Rhizoctonia solani AG 1 in Italy

Plant Disease ◽

10.1094/pdis-94-8-1071c ◽

2010 ◽

Vol 94 (8) ◽

pp. 1071-1071 ◽

Cited By ~ 2

Author(s):

A. Garibaldi ◽

G. Gilardi ◽

D. Bertetti ◽

M. L. Gullino

Keyword(s):

Rhizoctonia Solani ◽

Aqueous Suspension ◽

Its Region ◽

Morphological Characters ◽

Leaf Blight ◽

Pathogenicity Test ◽

First Report ◽

Leaf Petiole ◽

Perennial Plant ◽

Potted Plants

Woodland sage (Salvia nemorosa L.; Lamiaceae) is a hardy herbaceous perennial plant that is easy to grow and propagate and is used in parks and grown as potted plants. During the summer of 2009 in a nursery near Torino in northern Italy, a leaf blight was observed on 30-day-old plants of cv. Blau Koenigin grown in pots under shade. Semicircular, water-soaked lesions developed on leaves just above the soil line at the leaf-petiole junction and later along leaf margins. Lesions expanded along the midvein until the entire leaf was destroyed. Blighted leaves turned brown, withered, and clung to the shoots. No symptoms were observed on the roots. Severely infected plants died. Diseased tissue was disinfested for 10 s in 1% NaOCl, rinsed with sterile water, and plated on potato dextrose agar (PDA) amended with 25 mg/liter of streptomycin sulfate. A fungus with morphological characters of Rhizoctonia solani (3) was consistently recovered. Ten-day-old mycelium grown on PDA at 22 ± 1°C appeared light brown, rather compact, and with radial growth. Sclerotia were irregular and measured between 0.5 and 2 mm. Pairings were made with tester isolates of AG 1, 2, 3, 4, 5, 6, 7, 11, and AG B1. The only successful anastomosis was with tester isolate AG 1 (ATCC 58946). The hyphal diameter at the point of anastomosis was reduced, the anastomosis point was obvious, and cell death of adjacent cells was observed. Results were consistent with other reports on anastomosis reactions (2). The description of sclerotia of the isolate AG1 was typical for subgroup 1A Type 2 (3). The internal transcribed spacer (ITS) region of rDNA was amplified using primers ITS4/ITS6 and sequenced. BLASTn analysis (1) of the 688 bp showed a 100% homology with the sequence of R. solani AG-1A and the nucleotide sequence has been assigned (GenBank Accession No. HM044764). For pathogenicity tests, the inoculum of one isolate of R. solani from the nursery was prepared by growing the pathogen on PDA for 7 days. The foliage of 30-day-old potted plants of S. nemorosa cv. Blau Koenigin was artificially inoculated with an aqueous suspension of PDA and mycelium fragments (1 g per mycelium per plant) prepared from cultures with a blender. Plants were covered with plastic bags for 3 days. Plants inoculated with water and PDA fragments alone served as control treatments. Plants were maintained in a glasshouse at 20 to 25°C. The first symptoms, similar to those observed in the nursery, developed 7 days after foliar inoculation. R. solani was consistently reisolated from infected leaves. Control plants remained healthy. The pathogenicity test was carried out twice with similar results. To our knowledge, this is the first report of leaf blight of S. nemorosa caused by R. solani in Italy as well as worldwide. The importance of the disease is still unknown. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) D. E. Carling. Page 35 in: Rhizoctonia Species: Taxonomy, Molecular Biology, Ecology, Pathology and Disease Control. Kluwer Academic Publishers, the Netherlands, 1996. (3) B. Sneh et al. Identification of Rhizoctonia Species. The American Phytopathological Society, St Paul, MN, 1991.

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First Report of Black Spot Disease Caused by Alternaria alternata on Cherry Fruits in China

Plant Disease ◽

10.1094/pdis-04-12-0416-pdn ◽

2012 ◽

Vol 96 (10) ◽

pp. 1580-1580 ◽

Cited By ~ 6

Author(s):

Y. Z. Zhao ◽

Z. H. Liu

Keyword(s):

Alternaria Alternata ◽

Disease Incidence ◽

Black Spot ◽

Its Region ◽

Liaoning Province ◽

Broad Host Range ◽

Pathogenicity Test ◽

First Report ◽

Initial Stage ◽

Pathogenicity Tests

Cherry (Cerasus pseudocerasus) has become an economically important fruit in China in recent years. In June 2010, fruit spots were discovered on fruit grown in Dalian City, Liaoning Province, China and 30% of local-orchard trees were infected with the disease, reducing yield and fruit quality. Disease incidence increased up to 75% in 2011. At the initial stage of the infection, some small, light brown spots appeared on the fruit that gradually became round or irregular and dark brown, and a black-brown concentric ring formed in the advanced stage of the infection. As disease progressed, the lesions expanded, causing the fruit surface to become pitted, withered, and dead. The pathogen was isolated from infected fruit of four orchards by a tissue isolation method (1) and cultured on potato dextrose agar (PDA) at 25°C in the dark for one week. Colonies on PDA were initially white and became grayish brown over time. Conidiophores were single or fasciculate, straight or knee curved, gray-brown with regular septa, branched or unbranched, and 12.5 to 90.0 × 2.0 to 5.0 μm. Conidia were oval, obclavate, or obpyriform, brown or dark brown, surface smooth or spinulose with short columnar beaks, and 20.0 to 42.0 × 7.5 to 14.5 μm with three to eight transverse septa and zero to three longitudinal or oblique septa. The sporulation pattern appeared in bush branches. According to the morphology, the pathogen was identified as Alternaria alternata (Fr:Fr.) Keissler (2,3). The internal transcribed spacer (ITS) region of rDNA was amplified using the primers ITS1/ITS4 and the ITS sequence was 99% identical to A. alternata (GenBank Accession No. FJ228163). Pathogenicity tests were performed on detached, asymptomatic fruit. Six fruit were inoculated by placing a PDA plug containing mycelia on the upper surface of the fruit. Another six fruit received sterile PDA plugs. Fruit were cultured in petri dishes with a 12-h photoperiod at 25°C and 90% relative humidity. Black spot symptoms were observed on inoculated fruit but not control fruit after 5 days. The pathogen was reisolated from inoculated fruit and confirmed to be A. alternata. The pathogenicity test was repeated once. A. alternata has a broad host range, but to our knowledge, this is the first report of A. alternata infecting cherries in China. References: (1) Z. D. Fang. Research Methods of Plant Disease, 124, 1998. (2) E. G. Simmons. Alternaria themes and variations. Mycotaxon 37: 79, 1990. (3) T. Y. Zhang et al. Fungi Notes–Genera Alternaria in China, 16:32, 2003.

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First Report of Leaf Blight on Foxglove (Digitalis purpurea) Caused by Rhizoctonia solani AG-1-IA in Italy

Plant Disease ◽

10.1094/pdis-93-3-0318c ◽

2009 ◽

Vol 93 (3) ◽

pp. 318-318

Author(s):

A. Garibaldi ◽

G. Gilardi ◽

D. Bertetti ◽

M. L. Gullino

Keyword(s):

Rhizoctonia Solani ◽

Morphological Characteristics ◽

Its Region ◽

Leaf Blight ◽

Pathogenicity Test ◽

Uniform Size ◽

First Report ◽

Digitalis Purpurea ◽

Blastn Analysis ◽

Hyphal Diameter

Digitalis purpurea (Scrophulariaceae), foxglove, is used in flower gardens. In the spring of 2008, leaf blight was observed in a nursery near Biella (northern Italy) on 30% of potted 30-day-old plants grown in a peat substrate at temperatures from 20 to 25°C and relative humidity at 75 to 80%. Semicircular, water-soaked lesions developed on leaves just above the soil line at the blade-petiole junction and later along the leaf margins. Lesions expanded for several days along the midvein until the entire leaf was affected. Blighted leaves turned brown, withered, clung to the shoots, and matted on the surrounding foliage. Diseased tissue was disinfested for 10 s in 1% NaOCl, rinsed with sterile water, and plated on potato dextrose agar (PDA) amended with 100 mg/liter of streptomycin sulfate. A fungus with the morphological characteristics of Rhizoctonia solani was consistently and readily recovered, then transferred and maintained in pure culture (4). The isolates of R. solani obtained from affected plants successfully anastomosed with tester isolate AG 1 (ATCC 58946). The hyphal diameter at the point of anastomosis was reduced, the anastomosis point was obvious, and cell death of adjacent cells was observed. Results were consistent with other reports on anastomosis reactions (2). Pairings were also made with tester isolates AG 2, 3, 4, 6, 7, 11, and AG BI and anastomosis was not observed. Ten-day-old colonies grown on PDA appeared light brown, rather compact, and radial. Numerous sclerotia of uniform size (0.5 to 3 mm in diameter) and sometimes joined laterally were formed. Descriptions of mycelium and sclerotia were typical for subgroup IA Type 2 (4). The internal transcribed spacer (ITS) region of rDNA was amplified using primers ITS4/ITS6 and sequenced. BLASTn analysis (1) of the 724-bp fragment showed a 99% homology with the sequence of R. solani (GenBank Accession No. EU591800). The nucleotide sequence has been assigned GenBank Accession No. FJ467490. For pathogenicity tests, the inoculum of R. solani was prepared by growing the pathogen on PDA for 10 days. Plants of 30-day-old D. purpurea were grown in 10-liter containers (6 plants per container) in a steam disinfested peat/clay/perlite (70:20:10) substrate. Disks of PDA cultures were placed on leaves (1 cm2 of mycelium per plant). Plants inoculated with PDA alone served as control treatments. Three replicates were used. Plants were maintained in a growth chamber at 24 ± 1°C with 12 h light/dark. First symptoms developed 12 days after the artificial inoculation. R. solani was consistently reisolated from infected leaves and stems. Control plants remained healthy. The pathogenicity test was repeated twice. R. solani was isolated from a small percentage of infected seeds of D. purpurea in India (3). This is, to our knowledge, the first report of leaf blight of D. purpurea caused by R. solani in Italy as well as in Europe. The spread of R. solani in nurseries might cause a decrease in trade. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) D. E. Carling. Grouping in Rhizoctonia solani by hyphal anastomosis reactions in: Rhizoctonia Species: Taxonomy, Molecular Biology, Ecology, Pathology and Disease Control. Kluwer Academic Publishers, the Netherlands, 1996. (3) K. K. Janardhanan and D. Ganguly. Indian Phytopathol. 16:379, 1963. (4) B. Sneh et al. Identification of Rhizoctonia Species. The American Phytopathological Society, St Paul, MN, 1991.

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First Report of Leaf Blight on Hosta fortunei Caused by Rhizoctonia solani AG 4 in Italy

Plant Disease ◽

10.1094/pdis-93-4-0432c ◽

2009 ◽

Vol 93 (4) ◽

pp. 432-432 ◽

Cited By ~ 3

Author(s):

A. Garibaldi ◽

D. Bertetti ◽

M. L. Gullino

Keyword(s):

United States ◽

Rhizoctonia Solani ◽

Aqueous Suspension ◽

Its Region ◽

The United States ◽

Morphological Characters ◽

Leaf Blight ◽

Pathogenicity Test ◽

First Report ◽

Leaf Petiole

Hosta fortunei (Liliaceae) is used in semishaded areas of gardens for its lavender-colored flowers produced in midsummer. In April of 2008, in a greenhouse at the University of Torino, located in Grugliasco (northern Italy), a leaf blight was observed on 15% of potted 60-day-old plants growing at temperatures ranging between 20 and 25°C and relative humidity of 60 to 90%. Semicircular, water-soaked lesions developed on leaves just above the soil line at the leaf-petiole junction and later along leaf margins. Lesions expanded for several days along the midvein until the entire leaf was destroyed. Blighted leaves turned brown, withered, and clung to the shoots. Severely infected plants died. Diseased tissue was disinfested for 10 s in 1% NaOCl, rinsed with sterile water, and plated on potato dextrose agar (PDA) amended with 25 mg/liter streptomycin sulfate. A fungus with the morphological characters of Rhizoctonia solani (4) was consistently recovered, then transferred and maintained in pure culture. Ten-day-old mycelium grown on PDA at 22 ± 1°C appeared light brown, rather compact, and had radial growth. Sclerotia were not present. Isolates of R. solani obtained from affected plants were successfully anastomosed with tester isolate AG 4 (AG 4 RT 31 obtained from tobacco plants). Results were consistent with other reports on anastomosis reactions (2). Pairings were also made with tester isolates of AG 1, 2.1, 2.2, 3, 6, 7, 11, and BI, but no anastomosis was observed. The internal transcribed spacer (ITS) region of rDNA was amplified using primers ITS4/ITS6 and sequenced. BLASTn analysis (1) of the 646-bp fragment showed a 100% homology with the sequence of R. solani AG-4 AB000018. The nucleotide sequence has been assigned GenBank Accession No. FJ 534556. For pathogenicity tests, the inoculum of R. solani was prepared by growing the pathogen on PDA for 10 days. Six-month-old plants of H. fortunei were grown in 1-liter pots. Inoculum, which consisted of an aqueous suspension of PDA and mycelium disks (10 g of mycelium per pot), was placed at the collar of plants. Plants inoculated with water and PDA fragments alone served as control treatments. Five plants per treatment were used. Plants were maintained in a growth chamber at 20 ± 1°C. The first symptoms, similar to those observed in the nursery, developed 15 days after inoculation. R. solani was consistently reisolated from infected leaves and stems. Control plants remained healthy. The pathogenicity test was carried out twice with similar results. R. solani was reported on plants belonging to the genus Hosta in the United States (3). This is, to our knowledge, the first report of leaf blight of H. fortunei caused by R. solani in Italy as well as in Europe. References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) D. E. Carling. Grouping in Rhizoctonia solani by hyphal anastomosis reactions. In: Rhizoctonia Species: Taxonomy, Molecular Biology, Ecology, Pathology and Disease Control. Kluwer Academic Publishers, The Netherlands, 1996. (3) D. F. Farr et al. Fungi on Plants and Products in the United States. The American Phytopathology Society, St Paul, MN, 1989. (4) B. Sneh et al. Identification of Rhizoctonia species. The American Phytopathological Society, St Paul, MN, 1991.

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Verticillium Wilt Incited by Verticillium dahliae in Lupinus polyphyllus in Italy

Plant Disease ◽

10.1094/pdis-91-4-0459a ◽

2007 ◽

Vol 91 (4) ◽

pp. 459-459

Author(s):

A. Garibaldi ◽

D. Bertetti ◽

M. L. Gullino

Keyword(s):

Verticillium Dahliae ◽

Internal Transcribed Spacer ◽

Vascular Tissue ◽

Its Region ◽

Northern Italy ◽

Potato Dextrose Agar ◽

Pathogenicity Test ◽

Conidial Suspension ◽

Lupinus Polyphyllus ◽

Blastn Analysis

Lupinus polyphyllus Lindl., a perennial ornamental belonging to the Leguminosae family, is grown in gardens for flower beds and borders. During the summer of 2006, in several gardens located in the Biella Province (northern Italy), a new wilt of Lupine was observed in 20 to 30% of the plants. The vascular tissue in stems of affected plants appeared brown. These plants were stunted and developed yellow leaves with brown or black streaks in the vascular tissue. Verticillium dahliae was consistently isolated from symptomatic vascular tissue and leaves when cultured on potato dextrose agar (PDA) (3). Microscopic observations revealed hyaline hyphae, with many irregular, dark microsclerotia, ranging from 17 to 61 μm. Conidiophores showed two verticils of three elements. Conidia were hyaline, elliptical, single-celled, measuring 3.4 to 6.0 × 1.8 to 3.1 μm (average 4.5 × 2.4 μm). The ITS region (internal transcribed spacer) of rDNA was amplified using the primers ITS4/ITS6 (2) and sequenced. BLASTn analysis (1) of the 521 bp obtained showed an E-value of 0.0 with V. dahliae. The nucleotide sequence has been assigned GenBank Accession No. EF015891. Healthy 30-day-old plants (10 per treatment) of L. polyphyllus were inoculated by root dip with a conidial suspension (0.5 × 106 CFU/ml) of V. dahliae isolated from infected plants. Ten noninoculated plants served as control treatments. All plants were transplanted into pots filled with a mix of sphagnum peat/pomix/pine bark/clay (50:20:20:10) and grown outdoors at temperatures ranging from 15 to 25°C. First wilt symptoms and vascular discoloration in the roots, crown, and veins developed within 20 days on each inoculated plant and become evident after 50 days. V. dahliae was consistently reisolated from infected plants. Noninoculated plants remained healthy. The pathogenicity test was conducted twice. To our knowledge, this is the first report of V. dahliae on L. polyphyllus in Italy. A wilt caused by V. dahliae on L. polyphyllus was observed in the Netherlands in 1925 (4). References: (1) S. F. Altschul et al. Nucleic Acids Res. 25:3389, 1997. (2) D. E. L. Cooke and J. M. Duncan. Mycol. Res. 101:667, 1997. (3) G. F. Pegg and B. L. Brady. Verticillium Wilts. CABI Publishing, Wallingford, UK, 2002. (4) J. H. H. Van der Meer. Meded. Landbouwhogesch. Wagening. 28, 1925.

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Morpho-molecular identification and first report of Fusarium equiseti in causing chilli wilt from Kashmir (Northern Himalayas)

Scientific Reports ◽

10.1038/s41598-021-82854-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Ammarah Hami ◽

Rovidha S. Rasool ◽

Nisar A. Khan ◽

Sheikh Mansoor ◽

Mudasir A. Mir ◽

...

Keyword(s):

Dna Barcoding ◽

Pcr Amplification ◽

Its Region ◽

Fungal Species ◽

Pathogenicity Test ◽

Kashmir Valley ◽

Fusarium Equiseti ◽

Infected Root ◽

Fusarium Sp ◽

High Degree

AbstractChilli (Capsicum annuum L.) is one of the most significant vegetable and spice crop. Wilt caused by Fusarium Sp. has emerged as a serious problem in chilli production. Internal transcribed spacer (ITS) region is widely used as a DNA barcoding marker to characterize the diversity and composition of Fusarium communities. ITS regions are heavily used in both molecular methods and ecological studies of fungi, because of its high degree of interspecific variability, conserved primer sites and multiple copy nature in the genome. In the present study we focused on morphological and molecular characterization of pathogen causing chilli wilt. Chilli plants were collected from four districts of Kashmir valley of Himalayan region. Pathogens were isolated from infected root and stem of the plants. Isolated pathogens were subjected to DNA extraction and PCR amplification. The amplified product was sequenced and three different wilt causing fungal isolates were obtained which are reported in the current investigation. In addition to Fusarium oxysporum and Fusarium solani, a new fungal species was found in association with the chilli wilt in Kashmir valley viz., Fusarium equiseti that has never been reported before from this region. The studies were confirmed by pathogenicity test and re-confirmation by DNA barcoding.

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Infundibulicybe rufa sp. nov. (Tricholomataceae), a reddish brown species from southwestern China

Phytotaxa ◽

10.11646/phytotaxa.266.2.7 ◽

2016 ◽

Vol 266 (2) ◽

pp. 134 ◽

Cited By ~ 2

Author(s):

QI ZHAO ◽

YAN-JIA HAO ◽

JIAN-KUI LIU ◽

KEVIN D. HYDE ◽

YANG-YANG CUI ◽

...

Keyword(s):

Internal Transcribed Spacer ◽

Phylogenetic Analyses ◽

Biosphere Reserve ◽

Its Region ◽

Southwestern China ◽

New Taxon ◽

Line Drawings ◽

Phylogenetic Placement ◽

Molecular Phylogenetic ◽

Pileus Surface

Infundibulicybe rufa sp. nov., is described from Jiuzhaigou Biosphere Reserve, southwestern China. It is characterized by the combination of the following characters: umbilicate to slightly infundibuliform, reddish brown pileus; decurrent, cream lamellae; cylindrical stipe concolorous with the pileus surface. Molecular phylogenetic analyses using the nuclear ribosomal internal transcribed spacer (ITS) region indicates that I. rufa is closely related to I. mediterranea and I. bresadolana. A description, line drawings, phylogenetic placement and comparison with allied taxa for the new taxon are presented.

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