Phomopsis vexans (Phomopsis blight of eggplant).

2021 ◽  
Author(s):  
Keyword(s):  
Solanum Melongena ◽  
Seed Transmission ◽  
Fruit Rot ◽  
Damping Off ◽  
Cultural Methods ◽  
Large Numbers ◽  
Historical Distribution ◽  
Poor Seed ◽  
Phomopsis Vexans ◽  
Stem Lesions

Abstract P. vexans is a pynicidial anamorph with a teleomorph in the genus Diaporthe. Easily seedborne and producing large numbers of conidia, it causes disease in Solanum melongena [aubergine/brinjal/eggplant], its only significant host. This ranges from poor seed germination and damping-off of seedlings, to leaf and stem lesions and to fruit rot, both in the field and after harvest. The fungus has been reported from widely distributed areas of most continents, but only a few of those are in Europe and Africa, even though the climates are favourable. Seed transmission may explain its broad historical distribution, but limitation of its host range to a non-staple vegetable crop can allow for its avoidance and eradication by cultural methods. As a result, perhaps, it does not appear often on lists of restricted pathogens, even though it may cause yield losses of more than 50%.

Phomopsis vexans. [Descriptions of Fungi and Bacteria].

1972 ◽  
Author(s):  
E. Punithalingam
Keyword(s):  
Geographical Distribution ◽  
West Indies ◽  
Solanum Melongena ◽  
Fruit Rot ◽  
Primary Sources ◽  
Damping Off ◽  
The West ◽  
Leaf Spots ◽  
Phomopsis Vexans ◽  
Stem Lesions

Abstract A description is provided for Phomopsis vexans[Diaporthe vexans]. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Solanum melongena, S. wendlandii. DISEASE: The only economic host is eggplant or brinjal (Solanum melongena) and the disease is variously known as tip over, stem blight or canker, leaf blight or spot and fruit rot; damping-off can also take place. Leaf spots (up to 3 cm diam.) are conspicuous, irregular in outline and may coalesce; lower leaves may be affected first. In stem lesions the cortex dries and cracks, plants become stunted and girdling cankers cause death. Fruit spots are pale, sunken, conspicuous and may affect the whole fruit; fruit may drop or remain attached, becoming mummified after a soft decay. Pycnidia are abundant. GEOGRAPHICAL DISTRIBUTION: Widespread in N. America, the West Indies, and E. and central Asia, also in Africa (Senegal, Tanzania, Zambia) and Mauritius (CMI Map 329, ed. 2, 1968). The record from Australia (NSW) should be deleted. Additional records not yet mapped are: Brunei, Haiti, Iran, Iraq, Rumania. TRANSMISSION: Host debris and seed from infested fruit are primary sources of inoculum. Naturally infected seed germinates less well and more slowly (20: 621; 22: 511).

scholarly journals First Report of Bacterial Stem Rot Caused by Pectobacterium carotovorum subsp. carotovorum and P. carotovorum subsp. atrosepticum on Grafted Eggplant in Italy

Plant Disease ◽  
2001 ◽  
Vol 85 (8) ◽  
pp. 921-921 ◽  
Author(s):  
V. Catara ◽  
P. Bella ◽  
G. Polizzi ◽  
A. Paratore
Keyword(s):  
Relative Humidity ◽  
Pathogenic Bacteria ◽  
Solanum Melongena ◽  
Fruit Rot ◽  
Pathogenicity Test ◽  
Pectobacterium Carotovorum ◽  
Carotovorum Subsp ◽  
Dark Green ◽  
Stem Lesions ◽  
Physiological Tests

In December 1999, widespread dieback of eggplant (Solanum melongena L., hybrid Mission Bell), grafted onto the interspecific hybrid Beaufort (Lycopersicon esculentum × Lycopersicon hirsutum) and on tomato hybrid Energy, was observed during four rootstock evaluation trials in greenhouses in Sicily, Italy. Dark brown to black, firm but sometimes fissured lesions, 1 to 20 cm long, were observed just above the grafting point. Water-soaked, soft, dark green lesions that turned brown with age were observed on the upper stem. Extensive discoloration of vascular tissues and, in some cases, breakdown of the pith and stem hollowness occurred. Eggplant seedlings, present in the same experimental trials, did not show any symptoms. From symptomatic tissues, numerous bacterial colonies were obtained on nutrient dextrose agar. Bacteria from purified colonies were gram-negative, oxidase-negative, facultatively anaerobic pectolitic on crystal violet pectate agar, which is nonfluorescent on King's B medium. On the basis of biochemical and physiological tests (1), seven of 10 isolates were identified as Pectobacterium carotovorum subsp. carotovorum (Jones 1901) Hauben et al. 1999, comb. nov. (2), and the remaining three were identified as P. carotovorum subsp. atrosepticum (van Hall 1902) Hauben et al. 1999, comb. nov. (2). Four days after prick inoculation of the stems of eggplant and tomato plants, all isolates caused extensive collapse of stems and internal brown discoloration and hollowness, respectively. In a second pathogenicity test, basil leaves of grafted eggplants and eggplant seedlings were either removed or left intact. These plants were then sprayed with bacterial suspensions (108 CFU/ml) of one isolate of each pathogen. Plants were held at 100% relative humidity or in a low-moisture incubator. After 6 days incubation, stem lesions and vascular discoloration, typical of symptoms observed in greenhouses, were observed on plants held at 100% relative humidity. No symptoms were observed in unwounded plants or plants maintained in low relative humidity. Similar symptoms on grafted eggplant have been attributed to physiological disorders (3). To our knowledge, only P. carotovorum subsp. carotovorum has been reported on eggplant as causing fruit rot. References: (1) N. W. Schaad, ed. 1988. Laboratory Guide for Identification of Plant Pathogenic Bacteria, 2nd ed. American Phytopathological Society, St. Paul, MN. (2) L. Hauben et al. Int. J. Syst. Bacteriol. 41:582, 1999. (3) G. Ginoux and H. Laterrot. Rev. Horticole (Paris) 321:49, 1991.

Pythium deliense. [Descriptions of Fungi and Bacteria].

1966 ◽  
Author(s):  
G. M. Waterhouse
Keyword(s):  
Geographical Distribution ◽  
West Indies ◽  
Cucurbita Pepo ◽  
Carica Papaya ◽  
Solanum Melongena ◽  
Saccharum Officinarum ◽  
Fruit Rot ◽  
Damping Off ◽  
Tomato Seedlings ◽  
Hibiscus Esculentus

Abstract A description is provided for Pythium deliense. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Hibiscus esculentus, Lycopersicon esculentum, Nicotiana tabacum and Saccharum officinarum. Also on Capsicum annuum, Carica papaya, Cucumis sativus, Cucurbita pepo, Datura fastuosa, Petunia sp. and Solanum melongena on inoculation (Rangaswami, 1959; Herb. IMI). DISEASE: Causing damping-off of tomato seedlings, stem-burn of tobacco and fruit rot of okra. GEOGRAPHICAL DISTRIBUTION: Asia (Indonesia, Sumatra) and Australasia & Oceania (Australia, New Guinea, Papua); North America (? United States); Central America & West Indies (? N˜caragua). TRANSMISSION: Soil-borne.

Pythium myriotylum. [Descriptions of Fungi and Bacteria].

1966 ◽  
Author(s):  
G. M. Waterhouse
Keyword(s):  
Geographical Distribution ◽  
Robinia Pseudoacacia ◽  
Solanum Melongena ◽  
Aerial Mycelium ◽  
Zingiber Officinale ◽  
Soft Rot ◽  
Fruit Rot ◽  
Ananas Comosus ◽  
Damping Off ◽  
Pythium Myriotylum

Abstract A description is provided for Pythium myriotylum. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Ananas comosus, Arachis hypogaea, Carica papaya, Citrullus vulgaris, Cucumis sativus, Lycopersicon esculentum, Medicago sativa, Nicotiana tabacum, Oryza sativa, Phaseolus vulgaris, Robinia pseudoacacia, Solanum melongena, Zingiber officinale. DISEASES: Damping-off of seedlings including tobacco, black locust and watermelon; seedling root rot of lucerne, papaw and tomato; soft rot of ginger rhizomes and fruit rot of watermelon, cucumber and eggplant. GEOGRAPHICAL DISTRIBUTION: Common only in warm climates: Africa (Madagascar, Nigeria, Sierra Leone, South Africa); Asia (Ceylon, India, Sumatra); Australasia (Australia); North America (U.S.A.). TRANSMISSION: Soil-borne. Incidence reported highest in virgin soil containing abundant decomposing organic matter (37: 244). Spread by aerial mycelium under conditions of high humidity (10: 210). Transport over long distances on ginger rhizomes has been reported (22: 197).

Specific PCR‐based detection of Phomopsis vexans the cause of leaf blight and fruit rot pathogen of Solanum melongena L.

2019 ◽  
Vol 69 (5) ◽  
pp. 358-365
Author(s):  
A.C. Udayashankar ◽  
S. Chandra Nayaka ◽  
B. Archana ◽  
T.R. Lakshmeesha ◽  
S.R. Niranjana ◽  
...  
Keyword(s):  
Solanum Melongena ◽  
Leaf Blight ◽  
Fruit Rot ◽  
Specific Pcr ◽  
Phomopsis Vexans

Myrothecium roridum. [Descriptions of Fungi and Bacteria].

1970 ◽  
Author(s):  
M. Fitton
Keyword(s):  
Geographical Distribution ◽  
Trifolium Pratense ◽  
Tomato Fruit ◽  
Solanum Melongena ◽  
Damping Off ◽  
Hibiscus Esculentus ◽  
Myrothecium Roridum ◽  
Stem Lesions ◽  
Stem Cankers ◽  
Soil Level

Abstract A description is provided for Myrothecium roridum. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Plurivorous. On Antirrhinum, Coffea, Cucurbitaceae, Cyamopsis psoraloides, Gardenia, Gloxinia, Gossypium, Hibiscus esculentus, Hypocyrta, Lycopersicon esculentum, Molucella, Sesamum indicum, Solanum melongena, Trifolium pratense, Vigna unguiculata, Vinca, Viola. DISEASE: Commonly causing necrotic lesions or shot holes on leaves but can also occur on petioles, stems and fruit. Small, sometimes water-soaked, lesions increase to about 2.5 cm diam. ; they may be zonate and coalesce, defoliating the plant. On many hosts infection is most serious under nursery or glasshouse contitions. Infection leads to stem lesions, dieback of the crown and decay at soil level; this may resemble typical damping-off symptoms. Stem cankers have been reported on cotton and sunken lesions on the fruit of cantaloupe. On tomato fruit a firm, black rot develops, with a sharply delimited border between healthy and diseased tissue; the rotted part can be removed readily in one piece (25: 345; 35: 19; 36: 528; 41: 199; 44: 1586, 3367; 49: 503). GEOGRAPHICAL DISTRIBUTION: Widespread (CMI Map 458, ed. 1, 1969); possibly more serious in warmer regions. TRANSMISSION: Probably a common soil saprophyte, with the capacity to become actively parasitic under conditions not yet clearly definable. Infection of cotton bolls and carpel walls is reported (43, 3382b). Seed of C. psoraloides when inoculated gave only 16% germination compared with 93% for the uninoculated seed.

scholarly journals PCR based detection of Phomopsis vexans (Sacc. & Syd.) - The causative agent of leaf blight and fruit rot disease of Brinjal (Solanum melongena L.)

2013 ◽  
Vol 7 (1) ◽  
pp. 17-20 ◽  
Author(s):  
KM Jayaramaiah ◽  
S. Mahadevakumar ◽  
AP Charith Raj ◽  
GR Janardhana
Keyword(s):  
Solanum Melongena ◽  
Culture Method ◽  
Leaf Blight ◽  
Fruit Rot ◽  
Universal Primer ◽  
Conventional Culture ◽  
Detection Assay ◽  
Pcr Products ◽  
Phomopsis Vexans ◽  
Rot Disease

Leaf blight and fruit rot disease of brinjal (Solanum melongena) caused by the fungal pathogen Phomopsis vexans is the most prevailing diseases responsible for the significant yield loss in many Brinjal growing regions of India. The survey conducted during 2008-2010, seven (07) isolates of Phomopsis vexans causing leaf blight and fruit rot disease in different areas of Karnataka were isolated, identified and confirmed by Koch’s postulates. Identification of Phomopsis vexans by conventional culture method was time consuming and laborious. Hence, PCR based detection assay was used to detect the pathogen from DNA samples obtained from fungal isolates. Universal primer pairs designed from internal transcribed spacer regions ITS1 (5'-CGGATCTCTTGGTTCTGGCA-3') and ITS4 (5'-GACGCTCGAACAGGCATGCC-3') of the ribosomal DNA (rDNA) of the genus Phomopsis were used for PCR. The study revealed the amplification of expected 553bp PCR products in all the DNA samples isolated from different isolates of Phomopsis vexans confirming their association in leaf blight and fruit rot disease of Brinjal.DOI: http://dx.doi.org/10.3126/ijls.v7i1.8173 International Journal of Life Sciences 7(1): 2013; 17-20

scholarly journals First Report of Damping-Off Caused by Rhizoctonia solani AG-4 on Mediterranean Fan Palm in Italy

Plant Disease ◽  
2010 ◽  
Vol 94 (1) ◽  
pp. 125-125 ◽  
Author(s):  
G. Polizzi ◽  
D. Aiello ◽  
I. Castello ◽  
V. Guarnaccia ◽  
A. Vitale
Keyword(s):  
Rhizoctonia Solani ◽  
Disease Incidence ◽  
Morphological Characteristics ◽  
Mediterranean Area ◽  
Western Mediterranean ◽  
Fluorescent Light ◽  
Damping Off ◽  
Centraalbureau Voor ◽  
First Report ◽  
Stem Lesions

Mediterranean fan palm (Chamaerops humilis L.), one of just two autochthonous European palms, is native to the western Mediterranean Region in southwestern Europe and northwestern Africa. It can be found growing wild in the Mediterranean area. In Europe, this species is very popular as an ornamental plant. In March 2009, a widespread damping-off was observed in a stock of approximately 30,000 potted 1-month-old plants of C. humilis cv. Vulcano in a nursery in eastern Sicily. Disease incidence was approximately 20%. Disease symptoms consisted of lesions at the seedling shoot (plumule). Stem lesions were initially orange, turned brown, and followed by death of the entire plumule or eophyll. A fungus with mycelial and morphological characteristics of Rhizoctonia solani Kühn was consistently isolated from lesions when plated on potato dextrose agar (PDA) amended with streptomycin sulfate at 100 μg/ml. Fungal colonies were initially white, turned brown with age, and produced irregularly shaped, brown sclerotia. Mycelium was branched at right angles with a septum near the branch and a slight constriction at the branch base. Hyphal cells removed from cultures grown at 25°C on 2% water agar were determined to be multinucleate when stained with 1% safranin O and 3% KOH solution (1) and examined at ×400. Anastomosis groups were determined by pairing isolates with tester strains AG-1 IA, AG-2-2-1, AG-2-2IIIB, AG-2-2IV, AG-3, AG-4, AG-5, AG-6, and AG-11 on 2% water agar in petri plates (3). Anastomosis was observed only with tester isolates of AG-4, giving both C2 and C3 reactions (2). One representative isolate obtained from symptomatic tissues was deposited at the Fungal Biodiversity Centre, Centraalbureau voor Schimmelcultures (CBS No. 125095). Pathogenicity tests were performed on container-grown, healthy, 1-month-old seedlings. Twenty plants of C. humilis cv. Vulcano were inoculated near the base of the stem with two 1-cm2 PDA plugs from 5-day-old mycelial cultures. The same number of plants served as uninoculated controls. Plants were incubated in a growth chamber and maintained at 25°C and 95% relative humidity on a 12-h fluorescent light/dark regimen. Symptoms identical to those observed in the nursery appeared 5 days after inoculation and all plants died within 20 days. No disease was observed on control plants. A fungus identical in culture morphology to R. solani AG-4 was consistently reisolated from symptomatic tissues, confirming its pathogenicity. To our knowledge, this is the first report in the world of R. solani causing damping-off on Mediterranean fan palm. References: (1) R. J. Bandoni. Mycologia 71:873, 1979. (2) D. E. Carling. Page 37 in: Grouping in Rhizoctonia solani by Hyphal Anastomosis Reactions. Kluwer Academic Publishers, the Netherlands, 1996. (3) C. C. Tu and J. W. Kimbrough. Mycologia 65:941, 1973.

scholarly journals THE EGGPLANT BLIGHT AND FRUIT ROT IN PORTO RICO

1969 ◽  
Vol 13 (2) ◽  
pp. 35-57
Author(s):  
J. A. B. Nolla
Keyword(s):  
Bordeaux Mixture ◽  
Control Measure ◽  
Soil Surface ◽  
The United States ◽  
Labor Cost ◽  
Fruit Rot ◽  
Seedling Blight ◽  
Stem Blight ◽  
Phomopsis Vexans ◽  
Serious Disease

1. A serious disease of eggplants known in Porto Rico as "lunares de la hoja y tallo" and "podredumhre de la fruta", in the United States of North America as leaf blight, foot-rot, leaf-spot, stem-blight. fruit-rot, eggplant-blight and seedling-stem-blight and in Cuba as "mancha de la hoja" and "enfermedad del tallo" exists in Porto Rico. 2. All varieties of eggplant are more or less equally susceptible under Porto Rican conditions. Color of plant or of fruit has no bearing on susceptibility or resistance. 3. The disease usually brings a loss of 50 per cent or over of the crop. 4. The symptoms of the disease appear on all above-ground parts of the plant. A seedling blight, stem and petiole cankers, spots on leaf blades, fruit stalks and calices and a rotting of the young and mature fruit are produced. 5. The fungus may occur inside the seed. 6. The pathogene responsible for the malady is Phomopsis vexans (Sacc. & Sydow) Harter. 7. Variations of the fungus as have been observed elsewhere do not appear to occur in the fungus in Porto Rico. 8. The size of the pyenidiospores ranges from 5 to 8 microns in length to 1.3 to 3 microns in width. 9. The germ tube of a germinating spore may either enter through a stoma, enter through a wound or force its penetration through the cuticle. 10. Secondary cycles repeatedly occur in fields. 11. The fungus is capable of a saprophytic existence. 12. The prevailing temperature in Porto Rico seems adequate for spore germination. 13. Moisture is a very important factor in outbreaks of the disease. 14. The disease is probably controlled by a three- or four-years rotation. 15. Plants with the symptoms of the disease should be promptly removed from fields. 16. Although seed treatment is beneficial it never completely eliminates the pathogene. 17. Clean seed from unaffected fruit should be demanded. 18. Infested soils should be avoided in preparing seedbeds. 19. Inoculated soils can he rendered safe for seedlings if drenched with a 1-50 formaldehyde solution at the rate of one-half gallon per square foot of soil surface. An application of 4-4-50 Bordeaux mixture is highly beneficial but the formaldehyde treatment is to be preferred. The latter treatment will cost about two-thirds of one cent per seedling. 20. Bordeaux mixture (4-4-50) is quite effective in preventing seedling blight. The treatment is too expensive and therefore inapplicable under ordinary conditions. Bordeaux mixture may be of practical application where labor cost is reduced. The safest and cheapest control measure is to grow healthy seedlings and set them on in uninfested soils.

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