Relationship of phenotypic and genetic variation in Plantago lanceolata to disease caused by Fusarium moniliforme var. subglutinans

Summary Naturally established individuals of Plantago lanceolata with the inflorescence disease caused by Fusarium moniliforme var. subglutinans had more inflorescences and were more likely to be male-sterile than healthy plants. Half-sib families planted in the field varied in the percentage of diseased plants, the number of inflorescences per plant, the incidence of male-sterility, and the pattern of inflorescence phenology. The rankings of families with respect to disease incidence was, however, not simply related to their reproductive phenotypes. Plants derived from field genotypes with a history of disease were slightly more likely to become diseased than plants derived from healthy genotypes. Inflorescence infection was more severe on plants derived from genotypes with a known history of disease. Since the fungus reduces seed production in the plants it infects, differential incidence of disease based on plant phenotype and genotype may have ecological and evolutionary consequences for the host population.     

The Disease Cycle of Mango Malformation Induced by Fusarium moniliforme var. subglutinans and the Curative Effects of Mangiferin-Metal Chelates

Evidence is presented to suggest that the bunchy top, die-back, abnormal inflorescence and blossom blight disease of Mangifera indica are interlinked and can be expressed as a disease cycle in mango malformation. The morphological and biochemical connections among these symptoms, induced by Fusarium moniliforme var. subglutinans Wollenw. and Reink., are appraised. Partial control of the mango malformation has been accomplished by spraying the diseased parts with mangiferin-Zn²⁺ and mangiferin-Cu2+ chelates. The salutory effect of niangiferin-metal chelates is evidenced by the revival of normal balance of mangiferin and the micronutrients in the diseased parts, dechne in the fungal population and emergence of healthy shoots.     

Moniliformin produced by cultures of Fusarium moniliforme var. subglutinans isolated from swine feed

Feed samples from Iowa suspected of causing vomiting and enlarged vulva as well as mortalities of swine were examined for toxigenic fungi and mycotoxins Fusarium moniliforme Sheldon and F. moniliforme Sheldon var. subglutinans Wollenew. & Reink. accounted for 43% and 18.5%, respectively, of the total count of 4.75×10⁵ propagules filamentous fungi per gram of swine feed, but representatives of various Penicillium spp. and Aspergillus spp. were also found. Eight isolates of F. moniliforme var. subglutinans from the feed produced 51–540 g of moniliformin per g on cracked corn at 25°C for six weeks. Zearalenone was not detected in these corn fermentations. Eight isolates of F. moniliforme from the feed did not produce detectable amounts of either zearalenone or monoliformin on cracked corn. Moniliformin was not detected in the feed samples.     

Changes in nitrogen content in malformed inflorescence of mango caused by Fusarium moniliforme Sheld. var. subglutinans Wr. et Rg.

Abstract

Fusarium moniliforme Sheld. var. subglutinans Wr. et Rg. causes malformations in young inflorescences of mango and seriously affects fruit formation. Quantitative studies of total, soluble and protein nitrogen contents of malformed inflorescence of two cultivars, ‘Himsagar’ and ‘Bombai’ were made. Healthy inflorescences of the former cultivar showed slightly higher nitrogen content than that of the latter. After infection, considerable increases in both soluble and protein fractions of nitrogen were observed in both host varieties. The proportion of these two nitrogen fractions, however, showed some changes in ‘Bombai’ but in ‘Himsagar’ it remained more or less unaltered.     

Isolation of beauvericin as an insect toxin from Fusarium semitectum and Fusarium moniliforme var. subglutinans

Nonpolar methylene chloride-soluble extracts from the mycelia of Fusarium semitectum and Fusarium moniliforme var. subglutinans were toxic to Colorado potato beetles. The major toxic metabolite was isolated and found to be the cyclodepsipeptide, beauvericin. This is the first report of the isolation of beauvericin from the genus Fusarium.     

Ice Nucleus Production of Fusarium moniliforme var. subglutinans in Relation to Its Growth Characteristics

The effects of culture conditions on the ice nucleus production of Fusarium moniliforme var. subglutinans isolated from the gut of larvae of the rice stem borer (Chilo suppressalis Walker) were examined. The ice nucleus production was only affected by cultivation temperature and pH: the optimum temperature and pH were 15°C to 20°C and 4.0 to 6.0, respectively.     

Spatial patterns of disease induced by Fusarium moniliforme var. subglutinans in a population of Plantago lanceolata

Summary At low densities, Plantago lanceolata was less likely to have the inflorescence disease caused by the fungus Fusarium moniliforme var. subglutinans. Where the disease was found, as host density increased, the proportion diseased remained constant or decreased. The pathogen's inability to exploit high host densities may be due to both the long disease cycle and the reduced efficiency of disease spread in heterogeneous habitats. Diseased plants were randomly spaced early in the summer but were later found in clusters, probably as a result of localized spore dispersal. Spatial patterns of disease levels remained constant from year to year.     

Presence of a Root Malformation Factor in Culture Filtrates of Fusarium moniliforme var. subglutinans1

The presence of a root malformation factor, different from plant growth substances viz. NAA, GA₃, Kinetin and reduced Glutathion was demonstrated in culture filtrates of Fusarium moniliforme var. subglutinans, a fungus commonly associated with malformed mango tissues. Culture filtrate extracts of the fungus caused curling and stunting of maize and pea roots and formation of flap like growth at the tip of wheat roots, but failed to induce malformation in bean plants as reported, for malformin.     

Peroxidase and polyphenol oxidase activity in malformed mango inflorescence caused byFusarium moniliforme var.subglutinans

Peroxidase and polyphenol oxidase activities in malformed mango inflorescences of ‘Himsagar’ and ‘Bombay green’ oultivars wore found to be increased considerably following infection byFusarium moniliforme var.subglutinans. Whether such increased activities were due to their synthesis by the pathogen or the host, or both, was not studied although it was found that the pathogen was incapable of producing the enzymesin vitro. The activities of both the enzymes in infected tissues were found to increase considerably during the experimental period. It was found that activities of polyphenol oxidase were inhibited in the presence of sodium diethyldithiocarbamate and phenylthiourea; the former acted as chelating agent of Cu of the enzymes and the latter as a competitive inhibitor. Similarly, peroxidase activity was found to be inhibited by cycloheximide which acted as inhibitor of enzyme protein synthesis. The fact that the ‘Himsagar’ cultivar showed greater enzyme activity than the ‘Bombay green’ cultivar possibly suggests its higher resistance to the pathogen.     

Effect of Fusarium moniliforme var. subglutinans Infection on Mangiferin Production in the Twigs of Mangifera indica

The effect of Fusarium moniliforme var. subglutinans on the concentration of mangiferin (1,3,6,7-tetrahydroxyxanthone-C₂-beta-D-Glucoside) was studied. The role of the temperature gradient on the severity of infection and mangiferin production was examined in the light of the proliferation of the fungus. The infection prevented the transportation of mangiferin from the site of its synthesis to the storage site (bark). The variation in the concentration of mangiferin was attributed to its conversion to a polymeric quinone.     

Mycotic pneumonia caused by Fusarium moniliforme in an alligator

Fatal pulmonary infection in a captive alligator (Alligator mississippiensis) is reported. At necropsy, the animal appeared to be in excellent nutritional condition, but a severe necrotizing bronchitis with bronchiectasis was present. Histological examination revealed numerous branched, septate, hyaline hyphae within the necrotic debris lining the bronchi and rarely infiltrating into the adjacent stroma. The fungus cultured from the lung was identified as F. moniliforme.     

Nucleic Acid Content in Leafblight disease of Brassica oleracea var. botrytis caused by Alternaria brassicicola (Schw.) Wiltshire

The effect of Alternaria brassicicola (Schw.) Wiltshire infection on the changes of nucleic acids of Brassica oleracea var. botrytis was studied. An increase in vocal nucleid adds (57%), DNA (44%) and RNA (150 %) in infected leaves was found. The increase in RNA content was due to an increase of all the four nucleotide contents. Guanylic acid increased significantly more than the other three nucleotides. The increase in G/C ratio was also due to an increase in guanylic acid.     

Changes in total contents of saccharides,proteins and chlorophyll in malformed mango inflorescence induced by fusarium moniliforme var. subglutinans

Fusarium moniliforme var.subglutinans Wr. etRg. causes malformations of mango inflorescences that finally fail to fruit. The host-cultivar Himsagar showed higher contents of total saccharides, chlorophyll and protein than the cultivar Bombai. Considerable loss in saccharides and chlorophyll contents and increase in protein content as a result of malformation of inflorescence was recorded in both the host-cultivars which progressed with time.     

Comparative studies on the effect of vitamins on sporulation in Fusarium oxysporum schlecht. ex. Fr. and Fusarium moniliforme V. subglutinans Wr. & Rg.

On the basis of sporulation (total output of all the three spore forms taken together) and fungal mat production bothF. oxysporum Schlecht ex.Fr. andF. moniliforme v.subglutinans Wr. &Rg. are auxoheterotrophic for thiamine, biotin, inositol, riboflavin and pyridoxine. The first three vitamins are selective in accelerating macro-conidial production also inF. moniliforme, which otherwise shows decrease with advance in days of incubation.F. moniliforme is an auxo-autotroph for nicotinic acid, Ca-pantothenate and folic acid and auxoheterotroph for ascorbic acid. Auxoautotrophy for Ca-pantothenate, folic acid, l-ascorbic acid and p-aminobenzoic acid cannot be suggested forF. oxysporum. Whereas nicotinic acid is a depressent of sporulation inF. oxysporum, inF. moniliforme another vitamin p-aminobenzoic acid depresses sporulation. As the two species ofFusarium show differences in preference as well as inhibition to at least five of the vitamins studied and also varied trends of pH changes exists there is full justification for their separate taxonomic placements.     

Suppression of maize root diseases caused by Macrophomina phaseolina, Fusarium moniliforme and Fusarium graminearum by plant growth promoting rhizobacteria.

A plant growth-promoting isolate of a fluorescent Pseudomonas sp. EM85 and two bacilli isolates MR-11(2) and MRF, isolated from maize rhizosphere, were found strongly antagonistic to Fusarium moniliforme, Fusarium graminearum and Macrophomina phaseolina, causal agents of foot rots and wilting, collar rots/stalk rots and root rots and wilting, and charcoal rots of maize, respectively. Pseudomonas sp. EM85 produced antifungal antibiotics (Afa+), siderophore (Sid+), HCN (HCN+) and fluorescent pigments (Flu+) besides exhibiting plant growth promoting traits like nitrogen fixation, phosphate solubilization, and production of organic acids and IAA. While MR-11(2) produced siderophore (Sid+), antibiotics (Afa+) and antifungal volatiles (Afv+), MRF exhibited the production of antifungal antibiotics (Afa+) and siderophores (Sid+). Bacillus spp. MRF was also found to produce organic acids and IAA, solubilized tri-calcium phosphate and fixed nitrogen from the atmosphere. All three isolates suppressed the diseases caused by Fusarium moniliforme, Fusarium graminearum and Macrophomina phaseolina in vitro. A Tn5:: lacZ induced isogenic mutant of the fluorescent Pseudomonas EM85, M23, along with the two bacilli were evaluated for in situ disease suppression of maize. Results indicated that combined application of the two bacilli significantly (P = 0.05) reduced the Macrophomina-induced charcoal rots of maize by 56.04%. Treatments with the MRF isolate of Bacillus spp. and Tn5:: lacZ mutant (M23) of fluorescent Pseudomonas sp. EM85 significantly reduced collar rots, root and foot rots, and wilting of maize caused by Fusarium moniliforme and F. graminearum (P = 0.05) compared to all other treatments. All these isolates were found very efficient in colonizing the rhizotic zones of maize after inoculation. Evaluation of the population dynamics of the fluorescent Pseudomonas sp. EM85 using the Tn5:: lacZ marker and of the Bacillus spp. MRF and MR-11(2) using an antibiotic resistance marker revealed that all the three isolates could proliferate successfully in the rhizosphere, rhizoplane and endorhizosphere of maize, both at 30 and 60 days after seeding. Four antifungal compounds from fluorescent Pseudomonas sp. EM85, one from Bacillus sp. MR-11(2) and three from Bacillus sp. MRF were isolated, purified and tested in vitro and in thin layer chromatography bioassays. All these compounds inhibited R. solani, M. phaseolina, F. moniliforme, F. graminearum and F. solani strongly. Results indicated that antifungal antibiotics and/or fluorescent pigment of fluorescent Pseudomonas sp. EM85, and antifungal antibiotics of the bacilli along with the successful colonization of all the isolates might be involved in the biological suppression of the maize root diseases.     

Fumonisins--novel mycotoxins with cancer-promoting activity produced by Fusarium moniliforme.

Cultures on corn of Fusarium moniliforme MRC 826 are known to cause leukoencephalomalacia in horses and to be toxic and hepatocarcinogenic in rats. Culture material of this F. moniliforme isolate has also been shown to exhibit cancer-promoting activity in a short-term cancer initiation-promotion bioassay with diethylnitrosamine-initiated rats and the induction of gamma-glutamyl-transpeptidase-positive (GGT+) foci as an endpoint after 4 weeks of promotion. This bioassay was used as a monitoring system to isolate cancer-promoting compounds from cultures of F. moniliforme MRC 826. Culture material was successively extracted with ethyl acetate and CH3OH-H2O (3:1). Most of the cancer-promoting activity was recovered in the CH3OH-H2O extract and remained in the aqueous phase following partitioning of this extract between CH3OH-H2O (1:3) and CHCl3. The CH3OH-H2O fraction was chromatographed on an Amberlite XAD-2 column, and the active fraction was eluted with CH3OH. This fraction was chromatographed on a silica gel column with CHCl3-CH3OH-CH3COOH (6:3:1) as eluent and further purified on a C18 reverse-phase column. Two pure compounds were isolated, and these have been chemically characterized and given the trivial names fumonisin B1 and B2. At least 2 g of the major compound fumonisin B1 was purified from 1 kg of culture material. Fumonisin B1 in the diet (0.1%) significantly (P less than 0.001) induced the formation of GGT+ foci in the livers of initiated as well as noninitiated rats.(ABSTRACT TRUNCATED AT 250 WORDS)     

Transformation of 3-hydroxy-steroids by Fusarium moniliforme 7alpha-hydroxylase.

Transformation of physiologically important 3-hydroxy-steroids by the DHEA-induced 7alpha-hydroxylase of F. moniliforme was investigated. Whereas DHEA was almost totally 7alpha-hydroxylated, PREG, EPIA and ESTR were only partially converted into their 7alpha-hydroxylated derivatives because hydroxylation at other undetermined positions as well as reduction of ketone at C17 or C20 into hydroxyl also occurred. Cholesterol was not transformed by the enzyme. Kinetic parameters of the 7alpha-hydroxylation for these substrates were determined and confirmed that DHEA was the best substrate of the 7alpha-hydroxylase. Inhibition studies of DHEA 7alpha-hydroxylation by the other 3-hydroxy-steroids were also carried out and proved that DHEA, PREG, EPIA and ESTR shared the same active site of the enzyme. Induction effects of these steroids were compared, and DHEA appeared to be the best inducer of the 7alpha-hydroxylase of F. moniliforme.