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The genus Fusarium contains important mycotoxin-producing species that have been implicated in human diseases, such as alimentary toxic aleukia, Urov or Kashin-Beck disease, Akakabi-byo or scabby grain intoxication, and esophageal cancer. Many of these mycotoxin-producing species have also been implicated in several animal diseases, including hemorrhagic, estrogenic, emetic, and feed refusal syndromes, fescue foot, degnala disease, moldy sweet potato toxicosis, bean hulls poisoning, and equine leukoencephalomalacia. The interest in toxigenic Fusarium species is increasing world-wide due to the discovery of a growing number of naturally occurring Fusarium mycotoxins that have practical importance as threats to human and animal health.

Taxonomy of the genus Fusarium is complex and difficult to apply, partly because of the use of different taxonomic systems in different countries. The major taxonomic systems currently in use are discussed in a companion volume, "Fusarium Species: An Illustrated Manual for Identification" by Nelson et at. (1983). The taxonomy of the genus is further complicated by the extreme variability of Fusarium species in culture and the fact that they mutate and degenerate rapidly, particularly under conditions of repeated subculturing on common laboratory media. This situation has led to great confusion in the extensive literature on Fusarium mycotoxicology because the same fungus is known under a variety of different names, because different fungi are lumped together under names such as F. tricinctum Corda emend. Snyd. & Hans. and F. roseum Lk. emend. Snyd. & Hans., because several Fusarium toxins have been named for mis-identified producing species, because elaborate chemical and pathological studies have been reported in the literature and attributed to incorrectly named species, and because many toxigenic Fusarium strains have become degenerate and lost their toxigenic ability due to maltreatment in laboratories that do not specialize in the maintenance of Fusarium cultures. Consequently it has become impossible to relate toxicological studies done in different laboratories to each other because of the existing confusion with regard to the taxonomy and nomenclature of toxigenic Fusarium species (Smalley et al., 1977).

In this volume we discuss the toxigenic Fusarium species in relation to their i) incidence and distribution, ii) association with human and/or animal diseases, iii) toxicity to experimental animals, and iv) mycotoxins produced. This information is followed by a listing of the toxigenic strains of Fusarium species deposited in the International Toxic Fusarium Reference Collection. This volume provides all the available information on these strains through December 1981.

The preparation of the manuscript for this volume was made possible by the dedicated cooperation and assistance of Miss Rhoda Klass and Mrs. Carleen Schreuder, National Research Institute for Nutritional Disease, South African Medical Research Council; and Mrs. Jo Barnes, Mrs. Hendra de Villiers, Mrs. Laetitia van der Merwe, and Miss Elize Birch, Institute for Medical Literature, South African Medical Research Council. Mrs. Lois Klotz and Mrs. Nancy Fisher Gregory, Fusarium Research Center, The Pennsylvania State University, prepared cultures for examination and storage in the International Toxic Fusarium Reference Collection and also assisted in many other ways. Our special thanks to all of the individuals involved in research on toxigenic Fusarium species who supplied us with strains and information to use in establishing the International Toxic Fusarium Reference Collection. They are too numerous to name here but we express our appreciation to each of them.

Finally we express our appreciation to the Director of the Pennsylvania State University Press, Chris W. Kentera, and his fine staff for their patience and understanding during the preparation of this volume. Our association with the Press staff has been a most rewarding one and their assistance always makes our task easier.

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The only species accepted in this section by Nelson et al. (1983), F. oxysporum, has been reported to be toxigenic.

Perfect State: Unknown.

Fusarium oxysporum is a cosmopolitan soil saprophyte, and specialized pathogenic strains cause vascular wilt and damping-off diseases of a great variety of host plants (Booth, 1971; CMI Descriptions Nos. 27 and 28, 1964, and Nos. 211-220, 1970, Doidge,1938; Domsch et al., 1980; Gordon, 1956, 1960a; Meyer & Frank, 1979; Wollenweber & Reinking, 1935). Many pathogenic strains of F. oxysporum that are pathogenic only to specific hosts have been designated as formae speciales, e.g., F. oxysporum Schlecht. f. sp. carthami Klisiewicz & Houston, which causes wilt disease of safflower (Carthamus tinctorius L.).

Moldy Sweet Potato Toxicosis. A toxicosis of cattle characterized by severe pulmonary edema has been attributed to the presence of four furanoterpenoids in sweet potatoes (Ipomoea batatas L.) infected by F. lateritium (see both F. solani and F. monliforme, moldy sweet potato toxicosis). The lung edemagenic agents 1-ipomeanol, 4-ipomeanol, 1,4-ipomeadiol, and ipomeanine are formed when the furanosesquiterpenoid stress metabolite 4-hydroxymyoporone, formed by sweet potato tissue in response to non-specific stimuli, is catabolized by the pathogenic fungus F. solani (Burka et al., 1977). Although F. oxysporum is also a pathogen of sweet potato tubers and has been shown in vitro to be capable of converting 4-hydroxymyoporone to the lung toxic furanoterpenoids, it was much less effective (Burka et al., 1977). Consequently it is not known whether F. oxysporum plays any role in field outbreaks of atypical interstitial pneumonia in cattle consuming moldy sweet potatoes.

Another toxic substance known to occur in moldy sweet potatoes is the phytoalexin ipomeamarone, which is hepatotoxic and has an intraperitoneal LD50 of 230 mg/kg in mice (Wilson, 1973). Fusarium oxysporum causes surface rot of sweet potato tubers and has been found to be one of the agents that induces high concentrations (350 to 9,480 p.g/g) of ipomeamarone in infected sweet potato tissue, but not in surrounding healthy tissue (Martin et al., 1976). These authors concluded that this finding may account for the lack of human poisoning by eating sweet potatoes "because visibly diseased portions are discarded when sweet potatoes are being prepared for consumption." It is evident, however, that the consumption of moldy sweet potatoes is potentially dangerous to human health and that culled sweet potatoes should not be fed to animals.

Brine Shrimp. Extracts of cultures of F. oxysporum AUA 597 isolated from a carrot obtained from a supermarket in Alabama, USA, were reported to be toxic to brine shrimp by N.D. Davis et al. (1975). Extracts of potatoes inoculated with Carthami isolated from potatoes in Germany were also toxic to brine shrimp (Siegfried & Langerfeld, 1978). We have confirmed the identity of both of these isolates as F. oxysporum (Strains 11.1 and 11 .2). The mycotoxin(s) produced by these strains of F. oxysporum toxic to brine shrimp have not been chemically characterized.

Chickens. N.D. Davis et al. (1975) reported that extracts of cultures of F. oxysporum AUA 597 (Strain 11.1) caused 100% mortality of chick embryos. Extracts of cultures on nutrient amended shredded wheat incubated at 25°C for 21 days of F. oxysporum AUA 1078, isolated from grain sorghum in Alabama, USA, proved to be slightly toxic (1 of 7 dead) to day-old White Leghorn cockerels (Diener et al., 1981). The mycotoxin(s) produced by these two strains of F. oxysporum toxic to chick embryos and chickens have not been chemically characterized.

Cultures of F. oxysporum Sp. 1028, isolated from barley grains in Germany, were highly toxic to day-old White Leghorn chickens (Marasas et al., 1979b). We have confirmed the identity of this strain as F. oxysporum (Strain 11 .3). The toxicity of the culture material of this strain was due to the presence of high levels of moniliformin (see moniliformin, below).

According to Meronuck et al. (1970), cultures of an unspecified strain of F. oxysporum isolated from corn suspected of being toxic to cattle in the United States were highly toxic to chickens. Speers et al. (1972) reported that cultures of an unspecified isolate of F. oxysporum caused marked decreases in feed intake, body weight loss, and a complete cessation of egg production in laying hens. According to C.J. Mirocha (personal communication, 6 March 1978), the isolates referred to in the above two publications are the same isolate which was referred to as "F. roseum (isolate oxyrose)" by Mirocha & Christensen (1974). We have identified this isolate as F. semitectum (Strain 6.4) and it is consequently excluded from F. oxysporum.

Ducklings. Martin et al. (1971) reported that 32 of 63 isolates of F. oxysporum from foodstuffs in Swaziland were toxic to ducklings. However, in their lists of fungi isolated from different foodstuffs, F. oxysporum is not mentioned at all, while F. monliforme is recorded as a "species regularly present in all foodstuffs," whereas in their list of fungi tested for toxicity, F. monliforme is not mentioned, while 32 of 63 isolates of F. oxysporum are recorded as being toxic to ducklings. We conclude that the latter statement is a misprint for F. monliforme, and these isolates are consequently excluded from F. oxysporum.

Mice. According to Itakura & Kinosita (1975), the culture filtrate of one unspecified strain of F. oxysporum isolated from foodstuffs in Uganda was toxic to mice upon intraperitoneal injection.

A mouse bioassay in which culture filtrates or extracts of cultures are injected intraperitioneally in male dds mice has been used extensively in Japan for the detection of toxigenic Fusarium strains (Ueno et al., 1971a). Extracts of the following isolates of F. oxysporum have been found to be lethal to mice in this assay: unspecified isolate from paddy in Akita, Japan (Ueno et al., 1971a); isolate Abashiri-3 (Ueno et al., 1973a); NRRL 1943 (Strain 11.4) (Ueno et al., 1972b, 1973a); and five out of 24 isolates of F. oxysporum, including 5026 (Strain 11.5), from river sediments in Japan (Ueno et al., 1977b). Although some of these isolates of F. oxysporum toxic to mice, including 5026 (Strain 11 .5) identified as F. oxysporum by us, caused radiomimetic pathological changes characteristic of trichothecenes and also inhibited protein synthesis in rabbit reticulocytes, no known trichothecenes have been detected in the lethal extracts and the chemical nature of the mycotoxin(s) produced by these strains is unknown. Two other isolates toxic to mice and referred to as F. oxysporum "niveum" Melon-1 and Melon-2 by Ueno et al. (i973a) were, however, reported to produce the trichothecenes fusarenon-X and diacetylnivalenol (see mycotoxins produced, below). We have identified F. oxysporum "niveum" Melon-1 as a degenerate strain of F. sporotrichioides (Strain 4.11) and this strain is consequently excluded from F. oxysporum.

Extracts of F. lateritium 5013 and K.5036, isolated from river sediments in Japan, proved to be lethal to mice and to cause radiomimetic pathological changes (Ueno et al., 1977b). We have identified both of these isolates as F. oxysporum (Strains 11.6 and ii .7). No known trichothecenes could be detected in the toxic extracts of F. oxysporum (= F. latent/urn) 5013 (Strain ii .6). but this strain was found to produce zearalenone on autoclaved rice (lshii et al., 1974; Ueno et al., i977b). Isolate K.5036 (Strain 11.7) was found to produce diacetoxyscirpenol, diacetylnivalenol, neosolaniol, and two new tnchothecenes, 7-hydroxydiacetoxyscirpenol and 7,8-dihydroxydiacetoxyscirpenol (lshii, 1975; Ueno and Shimada, 1974; Ueno et al., i977b).

Pigeons. Chloroform extracts of cultures in Richard's solution incubated at 21°C for 21 days of a virulent (lMl 186539) and a weakly parasitic strain (lMl 166917) of F. oxysporum f. sp. carthami from wilt disease of safflower (Carthamus tinctorius L.) in India caused prolonged emesis in pigeons at non-lethal concentrations upon oral or intravenous administration (Ghosal et al., 1976a). The extracts were found by TLC to contain about six tnichothecene derivatives, of which two were identified as diacetoxyscirpenol and T-2 toxin (see mycotoxins produced, below).

Rabbits. Extracts of cultures of two isolates (F. oxysporum 2341 and F. redo/ens F. oxysporum] 2317) from ovenwintered cereals associated with outbreaks of ATA (see F. sporotnichioides, ATA) in the USSR were dermotoxic to rabbit skin (Joffe i960a, 1960b, 1971). Extracts of two out of five isolates (2131 and 3163) of F. oxysporum from goundnuts in Israel were also reported to be moderately dermotoxic to rabbit skin by Joffe (1973b). According to Joffe & Palti (1974), 149 of 155 unspecified isolates of Elegans Fusania exhibited some degree of dermotoxicity to rabbit skin. The toxic reactions ranged from a slight reddening of the skin to severe leucocytorrhea, edema, and necrosis. A quantitative relationship was also found between the dermotoxicity of these isolates and their phytotoxicity. The mycotoxin(s) produced by these dermotoxic isolates of F. oxysporum have not been chemically characterized.

Rats. According to Diener et al. (1976), extracts of F. oxysporum Auburn University No. 973, isolated from cotton in the United States and incubated on nutrient-amended shredded wheat at 25°C for 14 to 21 days, were toxic to rats upon dosing.

Tuttobello et al. (1974) reported that F. oxysporum Gaümann 1536/9 had uterotrophic effects in virgin weanling female rats when cultured either in liquid shake culture or in still culture on autoclaved corn. The chemical nature of the uterotrophic substance(s) was not determined, but the uterotrophic effect was equivalent to that of approximately 25 ppm "zearalanol" in the liquid and 12 ppm in the corn cultures.

A virulent (IMI 186539) and a weakly parasitic (IMI 166917) strain of F. oxysporum f. sp. carthami isolated from wilt disease of safflower in India were reported to be dermotoxic to rat skin by Ghosal et al. (1976a). When chloroform extracts of cultures in Richard's solution incubated at 21°C for 21 days were applied to the skin of rats, edema developed on the second day and the skin lesion became progressively severe, developing into hemorrhage and a heavy scab on the fourth day. When high doses were applied topically, the animals died within 6 days. These dermotoxic extracts were found by TLC to contain about six trichothecene derivatives, of which two were identified as diacetoxyscirpenol and T-2 toxin (see mycotoxins produced, below).

Turkeys. The strain of F. oxysporum reported to be highly toxic to turkey poults (Meronuck et al. 1970) and referred to as "F. roseum (isolate oxyrose)" by Mirocha & Christensen (1974), is F. semitectum (Strain 6.4) and is consequently excluded from F. oxysporum.

Diacetoxyscirpenol. lshii (1975) reported that Fusarium sp. K.5036, isolated from river sediments in Japan, produced diacetoxyscirpenol as well as four other trichothecenes (see Strain 11 .7) and this finding was confirmed (as F. latenitium 5036) by Ueno et al. (1977b). We have identified this strain as F. oxysporum (Strain 11.7).

According to Chakrabarti et al. (1976), a weakly parasitic strain (IMI 166917) of F. oxysporum f. sp. carthami isolated from safflower in India produced diacetoxyscirpenol that could be detected in roots and was also translocated to stems, leaves, and seeds of safflower plants grown in sterilized soil inoculated with this fungus. Diacetoxyscirpenol was also produced in Richard's medium incubated in still culture at 21°C for 21 days. The production of diacetoxyscirpenol (together with T-2 toxin; see T-2 toxin, below) in Richard's solution by this strain, as well as by a virulent strain (IMI 186539) of F. oxysporum f. sp. carthami, was confirmed by Ghosal et al. (1976a). The latter authors isolated 58 mg of crystals from 5 e of culture filtrate of isolate IMI 166917 and identified these crystals as diacetoxyscirpenol by melting point, optical rotation, and spectral properties. Ghosal et al. (1977a) detected diacetoxyscirpenol in seeds of safflower plants naturally infected by F. oxysporum f. sp. carthami in India. In addition to diacetoxyscirpenol (and T-2 toxin; see T-2 toxin, below), the above two Indian isolates of F. oxysporum f. sp. carthami have also been reported to produce several other unidentified trichothecene derivatives in Richard's solution and in inoculated safflower plants (Chakrabarti et al., 1976; Chakrabarti & Basu-Chaudhary, 1980; Ghosal et al., i976a).

Several authors have reported the non-production of trichothecenes, including diacetoxyscirpenol, by isolates of F. oxysporum: none of 11 isolates, including NRRL 1943 which we have identified as F. oxysporum (Strain 11.4) and excluding F. oxysporum "niveum" Melon-1 which we have identified as F. sporotnichioides (Strain 4.11), by Ueno et al. (1973a); none of 24, including 5026 which we have identified as F. oxysporum (Strain 11.5), by Ueno et al. (1977b); and none of 21 Suzuki et al. (1980, 1981b).

Diacetylnivalenol. Ueno et al. (1973a) reported that F. oxysporum "niveum" Melon-1 and Melon-2 produced diacetylnivalenol. We have identified isolate Melon-1 as a degenerate strain of F. sporotnichioides (Strain 4.11), and cultures of Melon-2 are no longer available; consequently, these two strains are excluded from F. oxysporum.

The production of diacetylnivalenol by Fusarium sp. K.5036 was reported by Ishii (1975) and confirmed by Ueno et al. (i977b), who referred to this strain as F. lateritium 5036. We have identified this strain as F. oxysporum (Strain ii .7).

7,8-Dihydroxydiacetoxyscirpenol. This new trichothecene was isolated from Fusarium sp. K.5036 by lshii (1975). The producing strain was referred to as F latent/urn 5036 by Ueno et al. (1 977b). We have identified this strain as F. oxysporum (Strain 11 .7).

Fusarenon-X. Ueno et al. (1973a) reported that F. oxysporum "niveum" Melon-1 (see Strain 4.11) and Melon-2 produced fusarenon-X. The former strain (as F. oxysporum T-M-i) was also found to produce small amounts of fusarenon-X by Ueno et al. (1975).

We have identified isolate Melon-1 as F. sporotnichioides (Strain 4.11), and cultures of Melon-2 are no longer available; consequently, these two strains are excluded from F. oxysporum.

According to Morooka et al. (1980), F oxysporum No. 55-1, isolated from cereals in Japan, produced fusarenon-X (but not deoxynivalenol or 3-acetyldeoxynivalenol) in liquid medium.

Fusaric Acid. Fusaric acid is a well-known phytotoxin that is produced by several Fusarium species, particularly pathogenic strains of F. oxysporum causing wilt diseases of a great variety of plants (Gaümann, 1957; Kern, 1972). Although fusaric acid is not generally regarded as a mycotoxin, some attention will be given here to fusaric acid production by F. oxysporum because fusaric acid as well as certain other phytotoxins such as lycomarasmin and lycomarasmic acid produced by F. oxysporum (Gaümann & Naef-Roth, 1950; Kern, 1972) are chelating agents and may be involved in certain diseases of abnormal bone development in animals (see F. moniliforme, abnormal bone development). In addition, fusaric acid is toxic to mice (intraperitoneal LD50 80 mg/kg) and death caused by the lethal dose has been attributed to its hypotensive effect (Hidaka et al., 1969). The ability of fusaric acid to cause significant decreases of blood pressure has also been observed in cats, dogs, rabbits, and rats and has been attributed to the inhibition of dopamine-3-hydroxylase (Bilai et al., 1975; Hidaka, 1971; Hidaka et aI., 1969). Fusaric acid has been administered to humans in clinical trials as an antihypertensive agent (Matta & Wooten 1973), in the treatment of Parkinson's disease (Hidaka, 1971; Matta & Wooten, 1973), and at dosage rates up to 1200 mg/day in the treatment of drug addiction (Pozuelo, 1976).

A positive correlation between pathogenicity to plants and the amount of fusaric acid produced has been found for many strains of F. oxysporum (Kern, 1970?). The production of fusaric acid in Richard's medium incubated at 21°C for 21 days has been reported for a weakly pathogenic (IMI 166917) as well as a virulent (IMI 186539) strain of F. oxysporum f. sp. carthami by Chakrabarti et al. (1976) and Ghosal et al. (i977b), respectively. However, Chakrabarti & Basu-Chaudhary (1980) found that an unspecified virulent strain of this fungus produced three times more fusaric acid (60-80 mg/e) than an unspecified "mild" strain (20-30 mg/e).

Surico & Graniti (1977) reported that unspecified virulent isolates of F. oxysporum f. sp. a/bed/n/s isolated from Bayoud diseased date palms (Phoenix dacty/ifena L.) in Algeria produced an average of 41 5 mg/e of fusaric acid and small amounts of anhydro-aspergillomarasmin B. We have identified one of these strains as F. oxysporum (Strain ii .8). Recently Mutert et al. (1981) detected moderate amounts (12-290 mg/e) of fusaric acid by HPLC in culture fluid of F. oxysporum f. sp. ap// CBS 184.38 and an isolate of F. oxysporum f. sp. p/si.

7-Hydroxydiacetoxyscirpenol. This new trichothecene was isolated from Fusarium sp. K.5036 by Ishii (1975). The producing strain was referred to as F. latent/urn 5036 by Ueno et al. (i977b). We have identified this strain as F. oxysporum (Strain 11.7).

Moniliformin. Fusarium oxysporum Sp. 1028, isolated from barley grain in Germany, produced 1,150 mg/kg of moniliformin in cultures on autoclaved corn incubated at 25°C for 2 weeks (Marasas et al., 1979b). We have confirmed the identity of this strain as F. oxysporum (Strain 11.3)

Neosolaniol. The production of neosolaniol by Fusarium sp. K.5036 was reported by Ishii (1975) and confirmed by Ueno et al. (1977b), who referred to the producing strain as F. latent/urn 5036. We have identified this strain as F. oxysporum (Strain 11 .7).

T-2 Toxin. According to Chakrabarti et al. (1976), a weakly parasitic strain (IMI 166917) ~of F. oxysporum f. sp. carthami isolated from safflower in India produced T-2 toxin that could be detected in roots and was also translocated to stems and leaves of safflower plants grown in sterilized soil inoculated with this fungus. T-2 toxin was also produced in Richard's solution incubated in still culture at 21°C for 21 days. The production of T-2 toxin (together with diacetoxyscirpenol; see diacetoxyscirpenol, above) in Richard's solution by this strain, as well as by a virulent strain (IMI 186539) of F. oxysporum f. sp. cartharmi, was confirmed by Ghosal et al. (i976a). The latter authors isolated 33 mg of crystals from 5 e culture filtrate of isolate IMI 166917 and identified these crystals as T-2 toxin by melting point, optical rotation, and spectral properties. Ghosal et al. (i977a) detected T-2 toxin in seeds of safflower plants naturally infected by F. oxysporum f. sp. carthami in India.

According to Nusrath (1979), two Indian isolates of F. oxysporum from wilt diseased chick peas and pigeon peas, respectively, produced unspecified levels of T-2 toxin (as well as zearalenone; see zearalenone, below) as determined by TLC in ethyl acetate extracts of cultures in Richard's medium incubated at 25°C for 14 days.

Several authors have reported the non-production of trichothecenes, including T-2 toxin, by isolates of F. oxysporum: none of ii, including NRRL 1943 which we have identified as F. oxysporum (Strain 11.4) and excluding F. oxysporum "niveum" Melon-1 which we have identified as F. sponotnichoides (Strain 4.11), by Ueno et al. (1973a); none of 24, including 5026 which we have identified as F. oxysporum (Strain ii .5), by Ueno et al. (1977b); and none of 21 by Suzuki et al. (1980, 198ib).

In conclusion, only four Indian isolates of F. oxysporum out of at least 56 tested have been reported to produce T-2 toxin. We have not seen any of these Indian isolates, and there are no known T-2 toxin-producing strains of F. oxysporum represented in the ITFRC.

Zearalenone. Mirocha & Christensen (1974) stated that F. oxysporum had been found to produce zearalenone in their laboratory, but gave no indication of the number of strains that had been found to be positive or of the levels produced. The strain reported as "F. roseum isolate oxyrose" to produce "copious amounts" of zearalenone by Mirocha & Christensen (1974), and previously referred to as F. oxysporum by Meronuck et al. (1970) and Speers et al. (1972), is F. semitectum (Strain 6.4).

Ishii et al. (1974) reported that one unspecified isolate of F. latent/urn produced zearalenone and this was confirmed by Ueno et al. (1977b), who referred to the producing strain as F. latent/urn 5013. We have identified this strain as F. oxysporum (Strain 11.6).

Fusarium sp. 5029, isolated from river sediments in Japan, was reported to produce unspecified levels of zearalenone by Ueno et al. (1977b). We have identified this strain as F. oxysporum (Strain 11.9).

According to Nusrath (1979), two Indian isolates of F. oxysporum from chick pea and pigeon pea, respectively, produced unspecified levels of zearalenone (together with T-2 toxin; see T-2 toxin, above) in Richard's solution incubated at 25°C for 14 days.

Several authors have reported on the non-production of zearalenone by isolates of F. oxysporum: none of 15 by Caldwell et al. (1970); neither of 2 by Eugenio et al. (1970a); none of ii by Ichinoe et al. (1977); none of 12 by Ishii et al. (i974a); none of 5 by Suzuki et al. (1978, i981b); and none of 24, including isolate 5026 which we have identified as F. oxysporum (Strain ii .5), by Ueno et al. (1 977b).

In conclusion, only two Indian isolates out of at least 70 isolates of F. oxysporum tested have been reported to produce unspecified levels of zearalenone. In addition, we have identified two zearalenone-producing isolates, F. latent/urn 5013 (lshii etal., 1974a; Ueno et al., 1977b) and Fusarium sp. 5029 (Ueno et al., 1977b), as F. oxysporum (Strains 11.6 and 11.9).

The toxigenic Fusarium strains listed in Table 11 .1 all have been identified as F. oxysporum according to Nelson et aI. (1983). Strains referred to as F. oxysporum in the literature but identified as other species by us are listed in Table ii .2.

This strain was isolated from a visibly moldy carrot obtained from a supermarket in Alabama, USA (ND. Davis et al., 1975). The fungus was cultured on autoclaved, nutrient amended shredded wheat at 25°C for 14 to 21 days. Chloroform-ethanol extracts of this culture material proved to be toxic (20-59% mortality) to brine shrimp and to cause 100% mortality of chicken embryos (ND. Davis et al., 1975). The chemical nature of the mycotoxin(s) produced by this strain is unknown.

A lyophilized culture of this strain was received on 10 March 1981 from U.L. Diener as "F. oxysporum No. 597."

Strain 11.2 F. oxysporum Berlin 62286 (= 0-1071; MRC 2199)

This strain was isolated from rotten potato tubers in Germany (Siegfried & Langerfeld, 1978). Potato tubers of two different cultivars were inoculated with this strain and incubated at 20°C until approximately one-third of each tuber was infected. The infected tissues were then separated and lyophilized, and purified ethyl-acetate extracts of them were assayed for toxicity to brine shrimp. Extracts of both cultivars proved to be toxic (50-80% mortality within 4 hours) to brine shrimp (Siegried & Langerfeld, 1978). The chemical nature of the mycotoxin(s) produced in inoculated potato tubers by this strain is unknown.

A slant culture of this strain was received on 20 January 1981 from E. Langerfeld as "F. oxysporum 62286 (Berlin)."

Strain 11.3 F. oxysporum Sp. 1028 ((0-916; MRC 1414)

This strain was isolated from barley grains from Bayreuth, Germany (Marasas et al., 1979b). Cultures on autoclaved corn incubated at 25°C for 2 weeks followed by 4 weeks at 10°C were toxic to day-old White Leghorn chickens and caused the death of 4 of 4 chickens in a mean time of 7.5 days after the consumption of an amount of feed equal to only 0.5% of that consumed by the controls (Marasas et al., 1979b). The toxicity of this culture material was due to moniliformin, which was detected in the meal at a level of 1,150 mg/kg.

A lyophilized culture of this strain was received on 17 October 1978 from W.F.O. Marasas as "F. oxysporum Sp. 1028."

Strain 11.4 F. oxysporum NRRL 1943 (= 0-1011; MRC 1694)

According to Ueno et al. (1972b), this strain was obtained from NRRL as F. oxysporum NRRL 1943 and was identified by W.L. Gordon, but the exact source is unknown to us. Extracts of cultures of this strain in PSC medium incubated in stationary culture at 26°C for 12 days were lethal to white mice upon intraperitoneal injection (Ueno et al., 1972b, 1973a). These extracts were negative in the rabbit reticulocyte assay for inhibition of

protein synthesis, and no trichothecenes were detected chemically. Consequently, the chemical nature of the mycotoxin(s) produced by this strain is unknown.

A lyophilized culture of this strain was received on 5 September 1979 from the NRRL as "F. oxysporum NRRL 1943."

Strain 11.5 F. oxysporum 5026 (0-1173; MRC 2564)

This strain was isolated from river sediments in Japan (Ueno et al., 1977b). Extracts of cultures in PSC medium incubated at 25 to 27°C for 2 weeks were lethal upon intraperitoneal injection in male dd YS mice (Ueno etal., 1977b). The pathological lesions in the mice that died were radiomimetic changes characteristic of trichothecenes, and the extracts also inhibited protein synthesis in rabbit reticulocytes. However, no known trichothecenes could be detected chemically in these extracts by Ueno et al. (1977b).

A slant culture of this pionnotal strain of F. oxysporum was received in November 1981 from Y. Ueno as "F oxysporum 5026."

Strain 11.6 F. lateritium 5013 ( = 0-1174; MRC 2566)

This strain was originally isolated from river sediments in Japan (Ueno et al., 1977b). Extracts of cultures in PSC medium incubated at 25-27°C for 2 weeks were lethal upon intraperitoneal injection in mice and caused radiomimetic pathological changes characteristic of trichothecenes (Ueno et al., i977b). However, no known trichothecenes could be detected in these extracts. This strain produced unspecified levels of zearalenone in cultures on autoclaved rice incubated at 24°C for 2 weeks followed by 1 week at 10- 15°C (Ueno et al., 1 977b). According to Ueno et al. (1 977b) this strain was previously also shown (as an unspecified strain of F. latent/urn) to produce zearalenone on rice by Ishii et al. (1974).

A slant culture of this pionnotal strain of F. oxysporum was received in November 1981 from Y. Ueno as "F. lateritium 5013."

Strain 11.7 F. lateritium K.5036 (= 0-1175; MRC 2567)

This strain (as Fusaniurn sp. K. 5036) was isolated from a sample of river water in Japan, according to lshii (1975); Ueno et al. (1977b) referred to this strain as F. lateritium 5036 and stated that it was isolated from river sediments in Japan.

Extracts of cultures in PSC medium incubated in stationary culture at 25°C for 14 days were lethal to mice and caused the radiomimetic injury characteristic of trichothecenes (Ueno et al., i977b). These extracts also inhibited protein synthesis in rabbit reticulocytes. This strain was shown to produce five trichothecenes, i.e., diacetoxyscirpenol, diacetylnivalenol, neosolaniol, and two new trichothecenes, 7-hydroxydiacetoxyscirpenol and 7,8-dihydroxydiacetoxyscirpenol (lshii, 1975; Ueno & Shimada, 1974; Ueno et al., 1977b).

In their description of the morphological characters of "F. lateritium 5036," Ueno et al.(1977b) stated that microconidia are absent, but in their drawings of this isolate they illustrated microconidia, macroconidia, unbranched and branched monophialides, and the terminal as well as intercalary chlamydospores quite typical of F. oxysporum.

A slant culture of this pionnotal strain of F. oxysporum was received in November 1981 from Y. Ueno as "F. lateritium 5036."

Stain 11.8 F. oxysporum ITM-150 (0-1 042; MRC 2066)

According to Surico & Graniti (1977), virulent isolates (unspecified) of F. oxysporum f. sp. albedinis obtained from date palms (Phoenix dactylifera L.) with Bayoud disease in Algeria during 1972, produced an average of 415 mg/c of fusaric acid and small amounts of anhydro-aspergillomarasmin B in zinc-amended Czapek-Dox medium incubated in shake culture at 25° for 8 days.

A slant culture was received on 18 September 1980 from A. Bottalico as "F. oxysporum f. sp. albedinis, ITM-150, fusaric acid producer." It is being assumed here that this pionnotal strain of F. oxysporum was one of the unspecified isolates used by Surico & Graniti (1977). This strain (as F. oxysporum ITM 150) did not produce deoxynivalenol in cultures on autoclaved corn incubated at 27°C for 4 weeks (Palmisano et al., 1981).

Strain 11.9 Fusarium sp. 5029 (0-1166; MRC 2536)

This strain was isolated from river sediments in Japan by Ueno et al. (1977b). Extracts of cultures in PSC medium were not toxic to mice and did not contain chemically detectable trichothecenes (Ueno et al., 1977b). Cultures on autoclaved rice incubated at 24°C followed by 1 week at 10-15°C contained unspecified levels of zearalenone (Ueno et al., 1 977b).

A slant culture of this pionnotal strain of F. oxysporum was received in November 1981 from Y. Ueno as "Fusarium sp. 5029."