scholarly journals Lateral Clipping of Canopy Influences the Microclimate and Development of Apothecia of Sclerotinia sclerotiorum in Carrots

Plant Disease ◽  
2005 ◽  
Vol 89 (6) ◽  
pp. 549-557 ◽  
Author(s):  
Cezarina Kora ◽  
Mary Ruth McDonald ◽  
Greg J. Boland
Keyword(s):  
Relative Humidity ◽  
Sclerotinia Sclerotiorum ◽  
Daucus Carota ◽  
Soil Surface ◽  
Canopy Architecture ◽  
First Report ◽  
Manual Removal ◽  
Sclerotinia Rot ◽  
Soil Temperatures ◽  
Canopy Management

Four canopy management treatments were evaluated in carrot (Daucus carota) production in Bradford Marsh, Ontario, in 2001 and 2002: (i) unclipped control; (ii) unclipped canopy with manual removal of collapsed senescing leaves at 2-week intervals following the first appearance on the soil; (iii) lateral clipping of the canopy at the initial emergence of apothecia, leaving the debris in the furrow, and (iv) lateral clipping of the canopy with manual removal of the debris from the furrow. Clipping reduced the canopy width by ca. 20% on both sides of the carrot bed by cutting off overlapping leaves above the furrow and senescing foliage on the soil surface. Maximum air and soil temperatures were up to 9.2 and 3.1°C lower, respectively, and relative humidity was up to 30% higher in unclipped canopies than in clipped canopies. The total number of apothecia in clipped plots was reduced by 74 and 76% compared with unclipped plots in 2001 and 2002, respectively. Canopy clipping reduced the quantity of apothecia in the crop by creating an unfavorable microclimate for the development of S. sclerotiorum without affecting the fresh foliar and root weights of carrot at harvest. The presence of clipped foliar debris in the furrow affected the number of apothecia in 2001; however, apothecia under the debris are unlikely to contribute to the overall inoculum in the crop. Lateral clipping also appeared to control Sclerotinia rot of carrot where it occurred (in 2001). This is the first report that documents and quantifies the effects of canopy architecture on the microclimate, development of apothecia of S. sclerotiorum, and Sclerotinia rot in carrot crops.

scholarly journals First Report of Sclerotinia Stem Rot and Watery Soft Rot Caused by Sclerotinia sclerotiorum on Sand Rocket (Diplotaxis tenuifolia) in Italy

Plant Disease ◽  
2005 ◽  
Vol 89 (11) ◽  
pp. 1241-1241 ◽  
Author(s):  
A. Garibaldi ◽  
A. Minuto ◽  
M. L. Gullino
Keyword(s):  
Relative Humidity ◽  
Sclerotinia Sclerotiorum ◽  
Severe Disease ◽  
Soil Surface ◽  
Soft Rot ◽  
Sclerotinia Stem Rot ◽  
First Report ◽  
Initial Symptoms ◽  
Stem Necrosis ◽  
White Mycelium

Several species of Diplotaxis (D. tenuifolia, D. erucoides, and D. muralis), known as wild or sand rocket, are widely cultivated in Italy. Rocket is used in Mediterranean cuisine as salad, a component of packaged salad products, and as a garnish for food. In winter 2003, a severe disease was observed on D. tenuifolia grown in unheated glasshouses on commercial farms near Albenga in northern Italy. Initial symptoms included stem necrosis at the soil level and darkening of leaves. As stem necrosis progressed, infected plants wilted and died. Wilt, characterized by the presence of soft and watery tissues, occurred within a few days on young plants. The disease was extremely severe in the presence of high relative humidity and mild temperature (15°C). Necrotic tissues became covered with white mycelium that produced dark sclerotia. Diseased stem tissue was disinfested for 1 min in 1% NaOCl and plated on potato dextrose agar (PDA) amended with 100 ppm streptomycin sulfate. Sclerotinia sclerotiorum (1) was consistently recovered from infected stem pieces. Sclerotia observed on infected plants measured 1.23 to 3.00 × 1.40 to 5.38 mm (average 2.10 × 2.85 mm). Sclerotia produced on PDA measured 1.00 to 4.28 × 1.00 to 6.01 mm (average 2.38 × 3.23 mm). Pathogenicity of three isolates obtained from infected plants was confirmed by inoculating 30-day-old plants of D. tenuifolia grown in 18-cm-diameter pots in a glasshouse. Inoculum, 2 g per pot of wheat kernels infested with mycelium and sclerotia of each isolate, was placed on the soil surface around the base of each plant. Three replicates of five pots each were used per isolate. Noninoculated plants served as controls. The inoculation trial was repeated once. All plants were kept at temperatures ranging between 10 and 26°C (average 15°C) with an average relative humidity of 80% and were watered as needed. Inoculated plants developed symptoms of leaf yellowing within 12 days, soon followed by the appearance of white mycelium and sclerotia, and eventually wilted. Control plants remained symptomless. S. sclerotiorum was reisolated from inoculated plants. To our knowledge, this is the first report of infection of D. tenuifolia by S. sclerotiorum in Italy as well as worldwide. The disease currently has been observed in the Liguria Region but not yet in other areas where sand rocket is cultivated. The economic importance of this disease for the crop can be considered medium at the moment, but is expected to increase in the future. Reference: (1) N. F. Buchwald. Den. Kgl. Veterin.er-og Landbohojskoles Aarsskrift, 75, 1949.

scholarly journals First Report of Sclerotinia sclerotiorum on Campanula carpatica and Schizanthus × wisetonensis in Italy

Plant Disease ◽  
2002 ◽  
Vol 86 (1) ◽  
pp. 71-71
Author(s):  
A. Garibaldi ◽  
A. Minuto ◽  
M. L. Gullino
Keyword(s):  
United States ◽  
Sclerotinia Sclerotiorum ◽  
Ornamental Plants ◽  
Soil Surface ◽  
The United States ◽  
First Report ◽  
Potted Plants ◽  
Initial Symptoms ◽  
Stem Necrosis ◽  
Campanula Carpatica

The production of potted ornamental plants is very important in the Albenga Region of northern Italy, where plants are grown for export to central and northern Europe. During fall 2000 and spring 2001, sudden wilt of tussock bellflower (Campanula carpatica Jacq.) and butterfly flower (Schizanthus × wisetonensis Hort.) was observed on potted plants in a commercial greenhouse. Initial symptoms included stem necrosis at the soil line and yellowing and tan discoloration of the lower leaves. As stem necrosis progressed, infected plants growing in a peat, bark compost, and clay mixture (70-20-10) wilted and died. Necrotic tissues were covered with whitish mycelia that produced dark, spherical (2 to 6 mm diameter) sclerotia. Sclerotinia sclerotiorum was consistently recovered from symptomatic stem pieces of both plants disinfested for 1 min in 1% NaOCl and plated on potato dextrose agar amended with streptomycin sulphate at 100 ppm. Pathogenicity of three isolates obtained from each crop was confirmed by inoculating 45- to 60-day-old C. carpatica and Schizanthus × wisetonensis plants grown in containers (14 cm diameter). Inoculum that consisted of wheat kernels infested with mycelia and sclerotia of each isolate was placed on the soil surface around the base of previously artificially wounded or nonwounded plants. Noninoculated plants served as controls. All plants were maintained outdoors where temperatures ranged between 8 and 15°C. Inoculated plants developed symptoms of leaf yellowing, followed by wilt, within 7 to 10 days, while control plants remained symptomless. White mycelia and sclerotia developed on infected tissues and S. sclerotiorum was reisolated from inoculated plants. To our knowledge, this is the first report of stem blight of C. carpatica and Schizanthus × wisetonensis caused by S. sclerotiorum in Italy. The disease was previously observed on C. carpatica in Great Britain (2) and on Schizanthus sp. in the United States (1). References: (1) D. F. Farr et al. Fungi on Plants and Plant Products in the United States. The American Phytopathological Society, St. Paul, MN, 1989. (2) J. Rees. Welsh J. Agric. 1:188, 1925.

scholarly journals First Report of White Mold Caused by Sclerotinia sclerotiorum on Oreganum vulgare and Taraxacum officinale in Italy

Plant Disease ◽  
2007 ◽  
Vol 91 (10) ◽  
pp. 1360-1360
Author(s):  
A. Garibaldi ◽  
A. Minuto ◽  
M. L. Gullino
Keyword(s):  
Sclerotinia Sclerotiorum ◽  
Soil Surface ◽  
Taraxacum Officinale ◽  
White Mold ◽  
Economic Losses ◽  
Medicinal Uses ◽  
First Report ◽  
Potted Plants ◽  
Mycelial Plug ◽  
Commercial Farms

Oreganum vulgare (wild marjoram) and Taraxacum officinale (dandelion) plants with culinary and medicinal uses are grown in the field and as potted plants in Liguria in northern Italy. In the spring of 2006, extensive chlorosis was observed on both crops on commercial farms. Economic losses were low. Symptoms included foliar necrosis and a watery decay of the stem at the soil level. Necrotic tissues became covered with a whitish mycelium that produced dark sclerotia. Eventually, affected plants wilted and died. Samples of diseased stem tissue were surface sterilized for 1 min in 1% NaOCl and plated on potato dextrose agar (PDA) amended with 100 mg/l of streptomycin sulfate. Sclerotinia sclerotiorum (Lib.) de Bary (1) was consistently recovered from diseased stem pieces. Sclerotia from infected O. vulgare plants measured 1.8 to 3.4 × 1.8 to 6.1 (average 2.5 to 3.6) mm. Sclerotia from these isolates measured 1.3 to 4.7 × 1.6 to 6.1 (average 2.7 to 3.4) mm on PDA. Sclerotia from infected T. officinale plants measured 1.8 to 3.4 × 1.8 to 6.1 (average 2.5 to 3.6) mm. Sclerotia from these isolates measured 1.7 to 5.2 × 2.0 to 5.7 (average 3.3 to 3.8) mm on PDA. Pathogenicity of three isolates obtained from O. vulgare and three isolates from T. officinale was confirmed on each host. Inoculum consisted of 1 cm2 of mycelial plugs excised from a 10-day-old PDA culture of each isolate. Plants were inoculated by placing a mycelial plug on the soil surface around the base of each plant. Ten plants were inoculated per isolate and an equal number of noninoculated plants served as controls. Plants were incubated at 10 to 27°C (average 18°C) and watered as needed. Pathogenicity tests were repeated once. All inoculated plants developed chlorosis within 12 to 18 days, followed by the appearance of white mycelium and sclerotia, and eventually wilt. Control plants remained symptomless. S. sclerotiorum was reisolated from inoculated plants of both hosts. To our knowledge, this is the first report of white mold on O. vulgare in Italy as well as worldwide and the first report of white mold on T. officinale in Italy. S. sclerotiorum is a well known pathogen of T. officinale (2) and its use as a mycoherbicide has been proposed (3). References: (1) N. F. Buchwald. Page 75. Den. Kgl. Veterin.er-og Landbohojskoles Aarsskrift, 1949. (2) D. M. McLean. Plant Dis. Rep. 35:162, 1951 (3) G. E. Riddle et al. Weed Sci. 39:109, 1991.

scholarly journals First Report of White Mold Caused by Sclerotinia sclerotiorum on Common Sage (Salvia officinalis) in Italy

Plant Disease ◽  
2004 ◽  
Vol 88 (9) ◽  
pp. 1044-1044
Author(s):  
A. Garibaldi ◽  
A. Minuto ◽  
M. L. Gullino
Keyword(s):  
Sclerotinia Sclerotiorum ◽  
Plant Density ◽  
Soil Surface ◽  
Salvia Officinalis ◽  
White Mold ◽  
Rooted Cuttings ◽  
First Report ◽  
Streptomycin Sulfate ◽  
High Plant Density ◽  
White Mycelium

Salvia officinalis L. is cultivated as an aromatic ornamental plant in Italy. In the spring of 2003, rooted cuttings grown in containers in commercial farms near Albenga (northern Italy) had soft and watery stem tissue covered with whitish mycelium at the soil level. Leaves and stems showed necrotic areas of irregular shape and size. As necrosis progressed, infected plants wilted and died. Wilt occurred within a few days on young plants. Because of high plant density, the pathogen spread rapidly within and across containers to infect many rooted cuttings. Sclerotinia sclerotiorum (Lib.) de Bary (2) was consistently recovered from infected stem pieces of Salvia officinalis that were disinfested for 1 min in 1% NaOCl and plated on potato dextrose agar (PDA) amended with 100 ppm of streptomycin sulfate. Sclerotia produced on PDA were ellipsoid and measured 1.4 to 4.2 × 1.1 to 2.1 (average 2.1 × 1.5) mm. Pathogenicity of three isolates obtained from infected plants was confirmed by inoculating 30-day-old plants grown in pots (14-cm diameter). Inoculum of each isolate was 14-day-old cultures of mycelium and sclerotia grown on sterile wheat kernels (300 g) and deionized water (320 ml) in a 1-liter flask at 20 to 25°C. Inoculum (10 g) of each isolate was placed on the soil surface around the base of 10 plants. Ten noninoculated plants served as controls. The inoculation trial was repeated once. All plants were kept in a screenhouse at temperatures ranging between 8 and 31°C and watered as needed. Inoculated plants developed symptoms of leaf yellowing, followed by the appearance of white mycelium within 7 days, and eventually wilted within 12 to 15 days. Control plants remained symptomless. White mycelium and sclerotia developed on infected tissues, and S. sclerotiorum was reisolated from inoculated plants on PDA amended with 100 ppm of streptomycin sulfate. To our knowledge, this is the first report of white mold of Salvia officinalis caused by S. sclerotiorum in Italy. The disease has been observed in Canada (1) as well as Tasmania and New Zealand. References: (1) G. J. Bolland and R. Hall. Can. J. Plant Pathol. 16:93, 1994. (2) N. F. Buchwald. Den. Kgl. Veterin.er-og Landbohojskoles Aarsskrift, 1949.

scholarly journals First Report of White Mold Caused by Sclerotinia sclerotiorum on Thymus × citriodorus in Italy

Plant Disease ◽  
2004 ◽  
Vol 88 (9) ◽  
pp. 1044-1044
Author(s):  
A. Garibaldi ◽  
A. Minuto ◽  
M. L. Gullino
Keyword(s):  
Sclerotinia Sclerotiorum ◽  
Soil Surface ◽  
White Mold ◽  
First Report ◽  
Potted Plants ◽  
Inoculation Trial ◽  
Initial Symptoms ◽  
Commercial Farms ◽  
Stem Necrosis ◽  
White Mycelium

Thymus × citriodorus is well known for the citrus aroma released by its leaves and is grown as a potted plant in northern Italy. This species is widely used in gardens and landscapes and for culinary purposes. In the Liguria Region alone, 1.5 million plants are grown. In the winter of 2002, extensive chlorosis was observed on potted plants of Thymus × citriodorus cv. Silver Queen grown outdoors on commercial farms near Albenga. Initial symptoms included stem necrosis at the soil level and darkening of leaves. As stem necrosis progressed, infected plants wilted and died. Wilt, characterized by the presence of soft and watery tissues, occurred within a few days on young plants. Necrotic tissues became covered with whitish mycelium that produced dark sclerotia. Sclerotinia sclerotiorum (Lib.) de Bary (1) was consistently recovered from infected stem pieces of Thymus × citriodorus. The diseased stem tissue was disinfested for 1 min in 1% NaOCl and plated on potato dextrose agar (PDA) amended with 100 ppm of streptomycin sulfate. Sclerotia produced on PDA were ellipsoid and measured 5.2 to 4.4 × 2.1 to 1.5 mm (average 3.5 × 3.0 mm). Pathogenicity of three isolates obtained from infected plants was confirmed by inoculating 30-day-old plants grown in 14-cm-diameter pots in a screenhouse. Inoculum that consisted of wheat kernels infested with mycelium and sclerotia of each isolate was placed on the soil surface around the base of each of 10 plants. Noninoculated plants served as controls. The inoculation trial was repeated once. All plants were kept at temperatures ranging between 5 and 26°C and watered as needed. Inoculated plants developed symptoms of leaf yellowing within 13 days, soon followed by the appearance of white mycelium, and eventually wilted. Control plants remained symptomless. White mycelium and sclerotia developed on infected tissues and S. sclerotiorum was reisolated from inoculated plants. To our knowledge, this is the first report of white mold of Thymus × citriodorus caused by S. sclerotiorum. The economic importance of this disease for the crop can be considered low. Reference: (1) N. F. Buchwald. Den. Kgl. Veterin.er-og Landbohojskoles Aarsskrift, 1949.

scholarly journals First Report of Sclerotinia sclerotiorum on Common Ragweed (Ambrosia artemisiifolia) in Europe

Plant Disease ◽  
1999 ◽  
Vol 83 (3) ◽  
pp. 302-302 ◽  
Author(s):  
Gy. Bohár ◽  
L. Kiss
Keyword(s):  
Sclerotinia Sclerotiorum ◽  
Aerial Mycelium ◽  
The United States ◽  
Ambrosia Artemisiifolia ◽  
American Phytopathological Society ◽  
Common Ragweed ◽  
First Report ◽  
Sclerotinia Rot ◽  
Stem Lesions ◽  
Test Plants

Common ragweed (Ambrosia artemisiifolia L.) is reported as a host of Sclerotinia sclerotiorum (Lib.) de Bary in North America (2,4), but not in Europe. A Hungarian survey of fungal diseases of ragweed in 1994 did not find sclerotinia rot of common ragweed (A. artemisiifolia var. elatior (L.) Descourt.) (1). In autumn 1998, mature ragweed plants, 1 to 1.5 m tall, were collected from the borders of four sunflower (Helianthus annuus L.) fields in which sclerotinia rot of sunflower was frequently observed during the season, and also from six other roadside sites in Hungary. Ragweed plants exhibiting symptoms characteristic of sclerotinia rot, i.e., wilting foliage and light brown, dry lesions on the stems, were found only near two sunflower fields. Black, round to irregular or oblong sclerotia were also observed on the infected ragweed plants both externally on the stem lesions and internally, in the pith cavity. Sclerotia measured up to 5 mm in diameter and were 5 to 14 mm long. After isolation on potato dextrose agar, the pathogen produced abundant aerial mycelium and large sclerotia characteristic of S. sclerotiorum. To confirm pathogenicity, potted seedlings and mature plants of ragweed were inoculated in the greenhouse with autoclaved wheat grains colonized with mycelia of S. sclerotiorum placed 0.5 to 1 cm from the collar of the test plants. Seedlings were killed in 2 to 3 days while mature plants wilted after 5 to 6 days. In a field test, six mature plants were inoculated by attaching mycelial disks to their stems with Parafilm. These plants wilted 12 to 14 days after inoculation. The pathogen was reisolated from all diseased plants. This is the first report of S. sclerotiorum on common ragweed in Europe. Nonsclerotial mutants of the fungus (3) are being produced to be tested as potential biocontrol agents of common ragweed, which has become not only the most widespread, but also the most important allergenic plant species in Hungary since the early 1990s. References: (1) Gy. Bohár and L. Vajna. Nōvényvédelem 32:527, 1996. (2) G. J. Boland and R. Hall. Can. J. Plant Pathol. 16:93, 1994. (3) G. J. Boland and E. A. Smith. Phytopathology 81:766, 1991.(4) D. F. Farr et al. 1989. Fungi on Plants and Plant Products in the United States. American Phytopathological Society, St. Paul, MN.

scholarly journals First Report of Sclerotinia sclerotiorum on Gazania sp. Hybrid in Italy

Plant Disease ◽  
2001 ◽  
Vol 85 (11) ◽  
pp. 1207-1207
Author(s):  
A. Garibaldi ◽  
A. Minuto ◽  
G. Gilardi ◽  
M. L. Gullino
Keyword(s):  
Sclerotinia Sclerotiorum ◽  
Soil Surface ◽  
Soft Rot ◽  
The United States ◽  
Crown Rot ◽  
First Report ◽  
Initial Symptoms ◽  
Leaf Yellowing ◽  
Stem Necrosis ◽  
Wheat Kernels

Gazania sp. hybrid is produced in pots in the Albenga Region of northern Italy for export to central and northern Europe. During fall 2000 to spring 2001, sudden wilt was observed in commercial plantings of this ornamental. Initial symptoms included stem necrosis at the soil level and yellowing and tan discoloration of leaves. As stem necrosis progressed, infected plants wilted and died. Wilt followed by soft rot occurred within a few days on young plants after the first leaf symptoms. Necrotic tissues became covered with white mycelia that produced dark, spherical (2 to 6 mm diameter) sclerotia. Sclerotinia sclerotiorum was consistently recovered from infected stem pieces of Gazania disinfested for 1 min in 1% NaOCl, plated on potato dextrose agar amended with streptomycin sulfate at 100 mg/liter. Pathogenicity of three fungal isolates was confirmed by inoculating 45- to 60-day-old plants grown in containers (14 cm diameter). Inoculum that consisted of wheat kernels infested with mycelium and sclerotia of each isolate was placed on the soil surface around the base of each plant. Noninoculated plants served as controls. All plants were maintained outdoors where temperatures ranged between 8 and 15°C. Inoculated plants developed symptoms of leaf yellowing, followed by wilt, within 7 to 10 days, while control plants remained symptomless. White mycelia and sclerotia developed on infected tissues, and S. sclerotiorum was reisolated from inoculated plants. To our knowledge, this is the first report of wilt of Gazania sp. hybrid caused by S. sclerotiorum in Italy. A crown rot of Gazania caused by S. sclerotiorum has been reported from California in the United States(1). Reference: (1) V. M. Muir and A. H. McCain. Calif. Plant Pathol. 16:1, 1973.

scholarly journals First Report of Sclerotinia Rot in Sword Bean Caused by Sclerotinia sclerotiorum in South Korea

Plant Disease ◽  
2020 ◽  
Vol 104 (3) ◽  
pp. 988-988
Author(s):  
I. Han ◽  
K. Park ◽  
H. Lee ◽  
S.-M. Lee ◽  
J. Shin ◽  
...  
Keyword(s):  
South Korea ◽  
Sclerotinia Sclerotiorum ◽  
First Report ◽  
Sclerotinia Rot

scholarly journals Sclerotinia Rot of Peucedanum japonicum Thunb. Caused by Sclerotinia sclerotiorum

2021 ◽  
Vol 27 (3) ◽  
pp. 115-119
Author(s):  
Won-Kwon Jung ◽  
Yang-Sook Lim ◽  
Min-Ki Kim ◽  
Jong-Su Kim
Keyword(s):  
Sclerotinia Sclerotiorum ◽  
Agar Medium ◽  
Potato Dextrose Agar ◽  
Brown Spot ◽  
Cylindrical Shape ◽  
Potato Dextrose Agar Medium ◽  
Partial Sequencing ◽  
Typical Symptom ◽  
First Report ◽  
Sclerotinia Rot

Sclerotinia rot was occurred on the leaf and stem of Peucedanum japonicum Thunb. in greenhouse field of Pohang city of Gyeongbuk province in Korea. The typical symptom of the disease was light brown spot and tipburn on infected leaves. The colony of the isolated fungus was white to light gray in color. Asci were cylindrical shape and 75‒240×5.9‒17.3 μm in size. Apothecia were cup-shaped with numerous asci and 0.5‒0.9 cm in size. Ascospores were aseptate and ellipsoid in shape, and 8.4‒10.7×4.8‒5.8 μm in size. Sclerotia formed on the plants and potato dextrose agar medium were globose to irregular in shape and black in color. Partial sequencing of rDNA of this isolate showed that it was 100% consistent with that of Sclerotinia sclerotiorum. It was confirmed that the same lesion was formed by reinoculating this pathogen on a healthy P. japonicum Thunb. and the same strain was isolated. This is the first report on the Sclerotinia rot of P. japonicum Thunb. caused by S. sclerotiorum in Korea.

Sign in / Sign up

Export Citation Format

Share Document