Seed transmission of Fusarium species and systemic infection in maize

The relative importance of several infection pathways (silks, stalks, and seed) leading to kernel infection of maize hybrids by Fusarium moniliforme was investigated in field experiments in 1993 and 1994. Systemic movement of specific fungal strains within plants was detected by using vegetative compatibility as a marker. Transmission of F. moniliforme from inoculated seed to stalks and developing kernels was detected in two of three field experiments; the seed-inoculated strain was detected in kernels on approximately 10% of ears. The percentage of kernels infected with the seed-inoculated strain ranged from 0 to 70%, with a mean of 0 to 2.5% (0 to 8.3% of F. moniliforme-infected kernels). Other pathways to kernel infection were more effective than seed transmission and systemic infection. F. moniliforme strains inoculated into the crowns and stalks of plants were found throughout the stalks and in up to 95% of the kernels in individual plants. Infection through the silks was clearly the most effective pathway to kernel infection. This was the only inoculation method that significantly increased overall incidence of F. moniliforme infection in kernels; the silk-inoculated strain infected up to 100% of the kernels in individual ears, with a treatment mean as high as 83.7% of kernels. When plants were silk-inoculated, the percentage of kernels infected by other F. moniliforme strains from the seed or stalk was reduced, apparently due to competition among strains. This study provides evidence that systemic development of F. moniliforme from maize seed and stalk infections can contribute to kernel infection, but silk infection is a more important pathway for this fungus to reach the kernels.

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Further studies on Carrot virus Y: hosts, symptomatology, search for resistance, and tests for seed transmissibility

Australian Journal of Agricultural Research ◽

10.1071/ar05028 ◽

2005 ◽

Vol 56 (8) ◽

pp. 859 ◽

Cited By ~ 6

Author(s):

R. A. C. Jones ◽

L. J. Smith ◽

B. E. Gajda ◽

T. N. Smith ◽

L. J. Latham

Keyword(s):

Host Species ◽

Field Survey ◽

Systemic Infection ◽

Seed Transmission ◽

Anethum Graveolens ◽

Additional Species ◽

Wild Carrot ◽

Natural Hosts ◽

New Locations ◽

Seed Transmissibility

Carrot virus Y (CarVY) was studied to provide information on its host range and symptoms, identify any alternative natural hosts and sources of host resistance in carrot germplasm, and determine whether it is seed-borne. Twenty-two species belonging to the Apiaceae were inoculated with CarVY by viruliferous aphids in the glasshouse. Systemic infection with CarVY developed in carrot itself, 4 other Daucus species, 5 herbs, 1 naturalised weed, and 2 Australian native plants. When 7 of these host species were exposed to infection in the field, all became infected systemically. In both glasshouse and field, the types of symptoms that developed in infected plants and their severity varied widely from host to host. Following inoculation with infective sap, the virus was detected in inoculated leaves of 1 additional species in the Apiacaeae, and 2 species of Chenopodiaceae. A field survey did not reveal any alternative hosts likely to be important as CarVY infection reservoirs. When 34 accessions of wild carrot germplasm and 16 of other Daucus spp. were inoculated with infective aphids, symptom severity varied widely among accessions but no source of extreme resistance to CarVY was found. Tests on seedlings grown from seed collected from individual infected plants or field plantings (most with CarVY incidences of >92%) of cultivated carrot (34 135 seeds), wild carrot (20 978 seeds), Anethum graveolens (22 921 seeds), and 3 other host species (3304 seeds) did not detect any seed transmission of CarVY. The implications of these results for control of the virus in carrot crops, minimising the losses it causes, and avoiding its introduction to new locations are discussed.

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Subterranean clover mottle virus infection of subterranean clover: widespread occurrence in pastures and effects on productivity

Australian Journal of Agricultural Research ◽

10.1071/ar9921597 ◽

1992 ◽

Vol 43 (7) ◽

pp. 1597 ◽

Cited By ~ 16

Author(s):

JM Wroth ◽

RAC Jones

Keyword(s):

Systemic Infection ◽

Subterranean Clover ◽

Trifolium Subterraneum ◽

Seed Transmission ◽

Dry Weight ◽

Widespread Occurrence ◽

Transmission Rates ◽

Type Isolate ◽

Growing Seasons ◽

South West

In 1989 and 1990, infection with subterranean clover mottle sobemovirus (SCMV) was widespread in subterranean clover ( Trifolium subterraneum L.) pastures in the south-west of Western Australia. The virus was detected in 61% of the pastures sampled and incidences of infection ranged from 1 to 50%. The virus was more common in old pastures than in pastures resown with newer cultivars during the preceeding 5 year period. When 12 isolates of SCMV were inoculated to subterranean clover plants grown in the glasshouse, symptoms varied from mild to severe. SCMV isolates P23 and F4 decreased the herbage dry weight of cw. Daliak and Woogenellup grown in plots as spaced plants by 81-88% while the Type isolate caused losses of 92%. By contrast, losses were 37-49% with cv. Karridale, a cultivar in which systemic infection was either delayed or prevented during winter. Infection decreased seed yield by c. 90% in cvv. Karridale and Woogenellup with all three isolates; seed weight was decreased 21-55%. A small proportion of cv. Woogenellup transplants outgrew the infection in new shoots during late spring to produce abundant healthy foliage. SCMV seed transmission rates in seed collected from infected transplants of cv. Woogenellup were 0.06, 0.07 and 0.43% for the Type, P23 and F4 isolates respectively. It was concluded that SCMV was present in most pastures, but at low incidences, and that it persists in them from year to year. Extended growing seasons and hard grazing are likely to increase its incidence.

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A MYCOLOGICAL STUDY OF CLINICAL SAMPLES FROM SUSPECTED MYCOSES IN A TERTIARY CARE HOSPITAL

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2018.v11i4.24127 ◽

2018 ◽

Vol 11 (4) ◽

pp. 267

Author(s):

Jitendra Chandra Devrari ◽

Varsha Saxena ◽

Vidya Pai

Keyword(s):

Fusarium Species ◽

Tertiary Care ◽

Systemic Infection ◽

Trichophyton Mentagrophytes ◽

Culture Technique ◽

Clinical Samples ◽

Care Hospital ◽

Superficial Infection ◽

Male Predominance ◽

Urease Test

Objective: The objective of this study was to isolate and identify the fungal agents obtained from clinical samples of suspected mycoses patients attending Yenepoya hospital.Methods: Various clinical samples obtained from patients were subjected to preliminary examination according to standard mycological protocols such as KOH mount, wet mount, Gram’s staining, and Indian ink examination. Causative organisms were identified by macroscopically and microscopically after growth on sabouraud’s dextrose agar (with or without cycloheximide and chloramphenicol) and confirmed by lactophenol cotton blue mount, slide culture technique, urease test, and growth on chrome agar accordingly.Results: Of 274 clinical samples, 125 were culture positive in which the fungal isolates obtained were dermatophytes (all 3 genera), Candida species (including Candida albicans), Fusarium species, Aspergillus fumigatus, and Cryptococcus neoformans. Male predominance was found among the patients being 6:3 male:female ratio.Conclusion: Among the superficial infection, Trichophyton mentagrophytes was found to be predominant isolates; however, in systemic infection, C. albicans was the predominant isolates.

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Characterization of Blueberry shock virus, an Emerging Ilarvirus in Cranberry

Plant Disease ◽

10.1094/pdis-04-17-0551-re ◽

2018 ◽

Vol 102 (1) ◽

pp. 91-97 ◽

Cited By ~ 2

Author(s):

Sara Thomas-Sharma ◽

Lindsay Wells-Hansen ◽

Rae Page ◽

Victoria Kartanos ◽

Erika Saalau-Rojas ◽

...

Keyword(s):

Virus Transmission ◽

Systemic Infection ◽

Seed Transmission ◽

Economic Consequences ◽

Enzyme Linked Immunosorbent Assay ◽

Polymerase Chain ◽

Marketable Fruit ◽

Mixed Virus Infection

Blueberry shock virus (BlShV), an Ilarvirus sp. reported only on blueberry, was associated with scarring, disfigurement, and premature reddening of cranberry fruit. BlShV was detected by triple-antibody sandwich enzyme-linked immunosorbent assay and reverse-transcription polymerase chain reaction, and isometric virions of 25 to 28 nm were observed in cranberry sap. The virus was systemic, although unevenly distributed in plants. The coat protein of BlShV from cranberry shared 90% identity compared with BlShV accessions from blueberry on GenBank. Phylogenetic analysis of isolates of BlShV from cranberry collected from Wisconsin and Massachusetts did not indicate grouping by state. BlShV was detected in cranberry pollen, and seed transmission of up to 91% was observed. Artificial inoculation of cranberry flowers by pollination did not cause virus transmission. In some Nicotiana spp., rub inoculation of leaves with homogenized BlShV-positive cranberry flowers resulted in systemic infection. Cranberry plants recovered from symptoms the year after berry scarring occurred but continued to test positive for BlShV. The virus caused significant reduction in the average number of marketable fruit and average berry weight in symptomatic cranberry plants but recovered plants yielded comparably with healthy plants. Although recovery may limit the immediate economic consequences of BlShV, long-term implications of single- or mixed-virus infection in cranberry is unknown.

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Sclerospora sacchari. [Descriptions of Fungi and Bacteria].

IMI Descriptions of Fungi and Bacteria ◽

10.1079/dfb/20056400453 ◽

1975 ◽

Author(s):

K. G. Mukerji

Keyword(s):

Geographical Distribution ◽

Stem Elongation ◽

Leaf Tissue ◽

Systemic Infection ◽

Seed Transmission ◽

Saccharum Officinarum ◽

Primary Host ◽

Downy Mildews ◽

Setaria Verticillata ◽

Host Infection

Abstract A description is provided for Sclerospora sacchari[Peronosclerospora sacchari]. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Saccharum officinarum, Echinochloa colonum, Eleusine indica, Euchlaena luxurians, E. mexicana, Panicum barbinodes, Polypogon interruptus, Saccharum barberi, S. robustum, S. sinense, Setaria verticillata, Sorghum halepense, S. sudanense, S. vulgare and Zea mays (35, 125; 40, 626; 44, 648), and others cereals and grasses. DISEASE: Downy mildew of sugarcane and one of the downy mildews of maize, the others are caused by Sclerospora philippinensis[Peronosclerospora philippinensis] (CMI Descript. 454) and S. maydis (Racib.) Butler. Sclerospora sacchari has larger oogonia than S. philippinensis; these spores are unknown in S. maydis which has smaller conidia than those of S. philippinensis. The symptoms on sugarcane differ, depending on when infection occurs. When diseased setts are used the young plant may die or become generally stunted, discoloured and conspicuous. Infection at a later stage causes pale green to yellow longitudinal stripes which increase in length after each leaf unfolds. The stripes may become a chlorotic mottling, later necrotic with oospores lying interveinally. Later infections cause abnormal stem elongation (jump up canes); stems are weak, have more internodes and fewer shorter leaves which may not unfold. Shredding caused by the disintegration of leaf tissue occurs in sugarcane but not in maize. In the latter host infection at a very early growth stage causes stunting and death. Systemic infection causes chlorotic leaf streaks, small poorly filed ears (formed in abnormally large numbers), elongated ear shanks, imperfect tassels with grain and sterility (21, 347; 42, 47, 629; 48, 1166). GEOGRAPHICAL DISTRIBUTION: Australia (Qd.), Fiji, India. Japan, Philippines, Taiwan, Thailand (CMI Map 21. ed. 2. 1965). Recent records from Central America are considered doubtful (49, 3185, 3740). TRANSMISSION: In Taiwan conidial air dispersal was mostly at 0100-0300hr (50, 3701). There is evidence for seed transmission in maize (47, 2705). The role of the oospore in spread appears uncertain, most spread in sugarcane apparently occuring through the conidia, but infection of this host with the sexual spore was successful (41, 544). The fungus passes readily from one primary host to the other.

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Peronospora trifoliorum. [Descriptions of Fungi and Bacteria].

IMI Descriptions of Fungi and Bacteria ◽

10.1079/dfb/20056400768 ◽

1983 ◽

Author(s):

S. M. Francis

Keyword(s):

Medicago Sativa ◽

Downy Mildew ◽

Geographical Distribution ◽

Systemic Infection ◽

Seed Transmission ◽

Field Conditions ◽

Infected Leaf ◽

Light Green

Abstract A description is provided for Peronospora trifoliorum. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Medicago sativa subsp. saliva, M. sativa subsp. falcata. DISEASE: Downy mildew of lucerne (alfalfa). Infected leaflets, which tend to be near the top of the stem, are light green or yellow. The affected areas can vary from small localized spots to larger areas of infected leaf or a systemic infection where the entire shoot may become yellow, stunted and swollen. GEOGRAPHICAL DISTRIBUTION: Worldwide, wherever lucerne is grown. CMI Map No. 343 includes records on clover and other hosts. TRANSMISSION: Mycelium is reported to overwinter in the crown bud (42, 617). Conidia are produced the following spring and in damp and humid conditions soon spread the disease. Oospores occur but reports on their frequency under field conditions are so few that it is difficult to assess their importance in overwintering the disease. Seed transmission, though suspected by Eriksson (1930) and also reported from Italy in a sample of seed from Argentina (Campbell, 1922), is thought to be unimportant (Richardson, 1979).

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A NEW SYMPTOM OF BACTERIAL CANKER RESULTING FROM SYSTEMIC INFECTION OF TOMATO FRUITS AND ITS IMPLICATIONS IN DISSEMINATION AND SEED TRANSMISSION

Canadian Journal of Plant Science ◽

10.4141/cjps66-062 ◽

1966 ◽

Vol 46 (4) ◽

pp. 371-374 ◽

Cited By ~ 2

Author(s):

R. E. C. Layne ◽

J. R. Rainforth

Keyword(s):

Systemic Infection ◽

Seed Transmission ◽

Bacterial Canker ◽

Tomato Fruits ◽

Tomato Plants ◽

Early Indicator ◽

Secondary Spread ◽

Green Tissue ◽

Infected Tomato

A new fruit symptom caused by systemic infection of tomato fruits with the bacterial canker organism, Corynebacterium michiganense (E.F. Sm.) Jensen, 1934, was observed in relation to previously reported fruit symptoms. Systemically infected fruits characteristically have a general mottled appearance with varying degrees of malformation. The extent of mottling and malformation depends on the size of the fruit when infected. Moderately affected fruits show islands of green tissue surrounded by whitish areas extending from the calyx scar to the distal end. Fruits more severely affected show distinct malformations, usually roughened and ridged in appearance with considerably more mottling. The distal ends are often white or near white. Affected fruits ripen later and the color is less uniform than comparable, healthy fruit. The mottle symptom becomes less distinct as the fruits ripen, and moderately affected fruits are difficult to distinguish from healthy ones.The fruit symptom described is a reliable early indicator of systemically infected tomato plants. Failure to recognize normal appearing plants with affected fruits as being systemically infected with C. michiganense could result in considerable secondary spread by mechanical means. Increased seed transmission could also occur by saving seed from ripened, apparently normal, but diseased fruits.

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Evaluation of Seed Transmission of Turnip yellow mosaic virus and Tobacco mosaic virus in Arabidopsis thaliana

Phytopathology ◽

10.1094/phyto.2000.90.11.1233 ◽

2000 ◽

Vol 90 (11) ◽

pp. 1233-1238 ◽

Cited By ~ 37

Author(s):

F. M. de Assis Filho ◽

J. L. Sherwood

Keyword(s):

Arabidopsis Thaliana ◽

Tobacco Mosaic Virus ◽

Mosaic Virus ◽

Seed Coat ◽

Virus Transmission ◽

Systemic Infection ◽

Seed Transmission ◽

Yellow Mosaic Virus ◽

Enzyme Linked Immunosorbent Assay ◽

Turnip Yellow Mosaic Virus

The mechanism of virus transmission through seed was studied in Arabidopsis thaliana infected with Turnip yellow mosaic virus (TYMV) and Tobacco mosaic virus (TMV). Serological and biological tests were conducted to identify the route by which the viruses reach the seed and subsequently are located in the seed. Both TYMV and TMV were detected in seed from infected plants, however only TYMV was seed-transmitted. This is the first report of transmission of TYMV in seed of A. thaliana. Estimating virus seed transmission by grow-out tests was more accurate than enzyme-linked immunosorbent assay due to the higher frequency of antigen in the seed coat than in the embryo. Virus in the seed coat did not lead to seedling infection. Thus, embryo invasion is necessary for seed transmission of TYMV in A. thaliana. Crosses between healthy and virus-infected plants indicated that TYMV from either the female or the male parent could invade the seed. Conversely, invasion from maternal tissue was the only route for TMV to invade the seed. Pollination of flowers on healthy A. thaliana with pollen from TYMV-infected plants did not result in systemic infection of healthy plants, despite TYMV being carried by pollen to the seed.

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Seed Transmission of Fusarium verticillioides in Maize Plants Grown Under Three Different Temperature Regimes

Plant Disease ◽

10.1094/pdis-91-9-1109 ◽

2007 ◽

Vol 91 (9) ◽

pp. 1109-1115 ◽

Cited By ~ 32

Author(s):

A. L. Wilke ◽

C. R. Bronson ◽

A. Tomas ◽

G. P. Munkvold

Keyword(s):

Temperature Regime ◽

Fluorescent Protein ◽

Fusarium Verticillioides ◽

Systemic Infection ◽

Seed Transmission ◽

Infection Process ◽

Effect Of Temperature ◽

Growth Stages ◽

Temperature Regimes ◽

Green Fluorescent

Fusarium verticillioides can be seed transmitted and cause systemic infection of maize; however, the frequency of these phenomena has varied widely among and within individual studies. In order to better understand this variability, we evaluated the effect of temperature on the first step in the systemic infection process, the transmission of F. verticillioides from seed to seedling. Seed of a commercial maize hybrid were inoculated with a strain of F. verticillioides that had been transformed with a gene for green fluorescent protein (GFP). The seed were planted in a greenhouse potting mix and incubated in growth chambers. Plants were incubated at one of three temperature regimes designed to simulate average and extreme temperatures occurring in Iowa during the weeks following planting. Root, mesocotyl, and stem tissues were sampled at growth stages V2 and V6, surface disinfested, and cultured on a semiselective medium. At V2, >90% of root and mesocotyl tissues was infected by the GFP-expressing strain at all three temperature regimes. Also at V2, infection was detected in 68 to 75% of stems. At V6, infection of root and mesocotyl tissues persisted and was detected in 97 to 100% of plants at all three temperature regimes. Plants also had symptomless systemic infection of belowground and aboveground internodes at V6. Infection of the three basal aboveground internodes was 24, 6, and 3% for the low-temperature regime; 35, 9, and 0% for the average-temperature regime; and 46, 24, and 9% for the high-temperature regime. Seed transmission and systemic infection occurred at all temperatures and did not differ significantly among treatments. These results indicate that, if maize seed is infected with F. verticillioides, seed transmission is common and symptomless systemic infection can be initiated under a broad range of temperature conditions.

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