P.J. Fisher

ENDOPHYTIC FUNGI OF MANILKARA BIDENTATA LEAVES IN PUERTO RICO

Endophytic fungi were isolated from healthy leaves of Manilkara bidentata (Sapotaceae) collected in Puerto Rico. One leaf was collected from each of three trees. Four 5 X 20 mm panels were cut from each leaf, surface sterilized, cut into 50 1 X 2 mm pieces, and plated on malt agar. Petioles were cut into ten 1 mm segments. Fungi were isolated from 90%-95% of the leaf pieces and all of the pet- iole segments. Xylaria spp. were found in 73%-74% of the leaf pieces in two of the three leaves, but only 21% in the third leaf. Xylaria cf. multiplex, X. cf. ad- scendens, a member of the X. mellisii/X. arbuscula complex, and 20 other fungal species were isolated. Nineteen of the 22 species on leaf blades were found on at least two of the three leaves, but half of the 12 species in petioles were unique to one leaf. The 22 species islolated from leaf blades fit a lognormal dis- tribution. An estimated three to six species were not discovered, indicating that the 22 species found on leaf blades represented 79%-88% of the endophytic community.

A comparative study of fungal endophytes in xylem and whole stem of Pinus sylvestris and Fagus sylvatica

Fifty-three endophytes were isolated from whole stem and xylem tissues taken from a mixed stand of Pinus sylvestris and Fagus sylvatica. Rhinocladiella atrovirens appeared confined to the xylem of Fagus, Coniothyrium cf, pini to the xylem of Pinus. Coryneum betulinum, Cryptocline sp. 1 and 2, Cylindrocarpon album and Melanconium atrum occurred in whole stems of Fagus only, Coniochaeta tetraspora and Sporormiella australis in whole stems of Pinus. Five species were non-host specific and occurred in all four morphological units. A cluster analysis showed that Pinus tissues can be separated from Fagus tissues on the basis of their endophyte populations, and a K-means cluster analysis revealed that eleven of the fungi isolated were mainly responsible for this separation. A discriminant analysis performed with these fungi demonstrated good discrimination between the four tissue sample groups.

Critique of the chitin assay technique for estimation of fungal biomass

Colorimetric determination of chitin content of nine aero-aquatic hyphomycetes showed that the conversion factor (CF) values (chitin content per unit dry weight of mycelium) varied with the age of mycelium, nutrient content of the medium, and initial oxygen concentration of the water. CF values often decreased with age of mycelium and also with lowered oxygen concentrations. Consequently, for estimation of fungal biomass in tissues, this technique is of limited value.

Fungal endophytes in Ulex europaeus and Ulex gallii

Three hundred and thirty-nine endophytic isolates were obtained from spines and stems of Ulex europaeus and U. gallii. The incidence of colonization with different endophytes showed a significant tendency to increase with advancing age of the host tissue.

Location of fungal endophytes in tissues of Suaeda fruticosa: A preliminary study

Twelve species of endophytic fungi were isolated from leaves and stems of Suaeda fruticosa. Colletotrichum phyllachoroides was entirely confined to leaves. Two species of Camarosporium were mainly isolated from the stems and a higher incidence of colonization was found for complete stems as compared with xylem. A qualitative comparison of the epiphytic fungi growing on unsterilized host pieces with the endophytic population of complete stems and xylem is presented and discussed.

Microfungi in the fungus gardens of the leaf-cutting ant Atta cephalotes : a preliminary study

Eighteen taxa and a number of sterile mycelia and yeasts were isolated from three fungus gardens of Atta cephalotes of which most reflected the endophytic and epiphytic fungal biota of the leaves of their food plants. The colonization frequency by Leucoagaricus gongylophorus varied from 72 to 95% depending on the food plants available to the ants and on whether the fungus gardens were sampled from a nest in the field or the laboratory. Infections per leaf unit which made up the fungus gardens varied from 1.31 to 1.63. A change in diet for one of the fungus gardens was accompanied by a significant reduction of filamentous fungi recorded from the nest. Comparisons of the incidence of the filamentous microfungi other than L. gongylophorus between the upper and lower portions of each nest and between colonies reveal significant heterogeneity. From 20 to 40% of leaf fragment from the colonies showed the presence of yeasts. The significance of the fungus garden on the health of the ant colony and the ultimate fate of microfungal invaders are briefly discussed.

Taxonomy and anamorphs of the Herpotrichiellaceae with notes on generic synonymy

The genera Capronia and Acanthostigmella are accepted in the Herpotrichiellaceae. Teleomorph-anamorph connexions are discussed. Four new species are described: Capronia acutiseta, C. villosa, C. coronata and C. pinicola . A key to the species is provided.

Aquatic hyphomycetes and other fungi in living aquatic and terrestrial roots of Alnus glutinosa

Sixty-six fungal endophytes, mainly Deuteromycotina, were isolated from the aquatic and terrestrial root systems of Alnus glutinosa . Twelve are mostly known from aquatic habitats; among them, Heliscus lugdunensis was isolated from ca 50% of all bark and xylem pieces examined. The mean colonization frequency by aquatic species in immersed roots was as high as 30% as opposed to 12% in soil roots and the total number of species found was also larger in aquatic roots. Results of cluster and correspondence analysis indicated that the aquatic and soil root samples are characterized by two different endophyte populations. The significance of water-submerged roots as substrata for aquatic hyphomycetes is discussed.

Fungal endophytes in Salicornia perennis

Thirty-two species of endophytic fungi were isolated from the stems of Salicornia perennis . Significant differences were found between colonization of old and new plant tissues. Pleospora salicorniae was found to colonize most parts of the plants whereas Pleospora bjorlingii was mostly confined to old plant tissue. Two species of Stagonospora were largely confined to new plant tissue. A multiple regression model revealed that P. salicorniae , two species of Stagonospora and to a lesser extent Diplodina salicorniae mainly account for the colonization of new tissues. The results are discussed in relation to the ecology of the host and the colonizing fungi.

An echinocandin from an endophytic Cryptosporiopsis sp. and Pezicula sp. in Pinus sylvestris and Fagus sylvatica

Fermentation broths of Cryptosporiopsis sp. and Pezicula sp. yielded the same echinocandin as is produced by the unrelated fungus Zalerion arboricola . The compound showed antimicrobial properties against certain yeasts.