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Publisher Summary This chapter focuses on Phaffia genus, whose vegetative cells are ellipsoidal and occur singly, in pairs, and occasionally in short chains, and reproduce by enteroblastic budding. Carotenoid pigments are synthesized (mainly astaxanthin and a minor proportion of P-carotene), which give cells en masse a red to salmon-red color. Phaffia appears to have a restricted geographic distribution, nine strains of which were isolated in the mountainous locations in a wide area of Japanese islands and a single strain came from Alaska, U.S.A. The only member species of this genus is Phaffia rhodozyma. Because of its high astaxanthin content, Phaffia rhodozyma has been used as a dietary pigment source to impart the desirable orange-red color to the normally white flesh of pen-reared salmonids and crustaceans.

Publisher Summary This chapter focuses on Eremothecium genus and its constituent species. The budding cells of this genus are absent or present, and when present, budding is multilateral on a narrow base. The cells are globose, ovoidal, ellipsoidal, or cylindroidal. Its asci, which become deliquescent, form 8-32 ascospores that are fusiform or acicular. Ascospores may have a central septum, and those of some species have a tapered, terminal extension of the cell wall. The sugars are fermented by some species and nitrate is not assimilated. The constituent species of this genus include Eremothecium ashbyi, Eremothecium coryli, Eremothecium cymbalari, and Eremothecium gossypii. The asci of Eremothecium ashbyi are ellipsoidal to fusiform, and occur mostly intercalary and in long chains. The ascospores are evenly distributed in the ascus, and are hyaline, narrow, sickleshaped, rounded at the tip, but with a basal spine. The Asci in Eremothecium coryli are long, curved cylindrical cells with rounded ends, although they are sometimes of irregular shape. Examination under the light microscope reveals the presence of vacuoles and a difference of refringence between the two halves of the spores. When stained with the Ziehl–Neelsen or the Schaeffer–Fulton malachite green technique, the half supporting the whip-like appendage is not acid fast and does not retain the malachite green.

Publisher Summary This chapter focuses on Cyniclomyces genus and its constituent species. The cells of this genus are long-ovoidal to cylindrical. In liquid media they occur in branched chains and in solid media, they are mainly singles or pairs. Vegetative reproduction occurs through budding at the poles or on broad shoulders, and in liquid media a layer of sediment is formed. Ascospores in this genus are ovoidal to cylindrical, one to four per ascus. No conjugation of cells occur prior to sporulation, and upon germination, an exosporium is evident. Fermentation of sugars is weak and growth occurs only between 30 and 40°C. Amino acids, B-vitamins, and an increased level of CO2 in the gas atmosphere are required for growth. The only member species of this genus is Cyniclomyces guttulatus. When a plate of yeast autolyzate-Proteose-peptone-glucose agar (pH4.5) is inoculated with cells of C. guttulatus, smooth, semiglossy colonies appear after 24 hours, provided the plates are incubated in an atmosphere high in CO2 content. No conjugation immediately precedes ascospore formation and the vegetative cells are presumed to be diploid. Asci contain one to four (rarely more) ovoidal to cylindrical ascospores, which lie free in the ascus. Thisarrangement is quite different from the tightly fitting spores in asci of species of Saccharomyces.

Forty-one isolates of Botrytis cinerea Fr. collected from 34 nurseries (mainly from tomato and lettuce crops) and 72 isolates from a tomato experiment were examined for tolerance in vitro to benomyl. Six of the nursery isolates grew in the presence of 500 ppm benomyl and five of these came from lettuce crops. Almost all of the remaining 35 isolates were completely inhibited by 0·5 ppm. None of the 72 isolates from the tomato experiment, which included various benomyl treatments, was as tolerant although several grew at 12·5 ppm benomyl. Three benomyl-tolerant isolates were tested and found to be similarly tolerant to the related compounds thiophanate-methyl, thiabendazole and BAS 3460F. Benomyl tolerance was not lost after ten successive subcultures on agar in the absence of benomyl.

Terremutin, a new metabolite isolated from cultures of an Aspergillus terreus mutant, has been characterized as 4,5-dihydroxy-3-methyl-7-oxabicyclo[4.1.0]hept-3-en-2-one. The complete stereochemistry is presented.

Thalli of Marchantia polymorpha were irradiated with Co60 gamma rays at exposures up to 55 kR and scored for survival after 4 weeks of growth. The reproductive integrity of the two apical cells of the thalli was inhibited by exposures lower than those required for complete lethality of the thalli. The nuclei of these apical cells are approximately 9·4 times larger than those in the vegetative cells adjacent to the proximal end of the rhizoids (116·6 ±13·0 μ3 vs. 12·4 ±1·1 μ3). At the 100 per cent lethal exposure the energy absorbed by the interphase chromosomes of the vegetative cells of the thallus is within the 95 per cent confidence limits as previously predicted for chromosomes of similar size in higher plants. The radiosensitivity of the thallus, however, is different from that of the gemma when sensitivity is based on an energy absorption basis: the thallus is approximately 4·3 times more sensitive than the gemmae.

Commercial production of Shiitake, Lentinus edodes , in the United States in 1985 was estimated at 400, 000 kg, most destined for the fresh market. The technology for indoor production in supplemented sawdust media currently employed by the U.S. growers is primarily adapted from that developed in Japan, Taiwan and mainland China, and significant changes do not appear warranted at the present time.

Yeasts were isolated from the crop and/or gut contents of foraging honey bees which were captured upon their return to the hive near Davis, California during a yearlong study. One hundred eighty-one yeasts were isolated from 194 pollen-collecting (PC) bees while 381 yeasts were isolated from 209 nectar-collectors (NC). Ascosporogenous yeasts (27%) included species of Debaryomyces (2 isolates), Hanseniaspora (36), Kluyveromyces (13), Metschnikowia (79), Pichia (20) and Saccharomyces (2). Asporogenous isolates (73%) were represented by Candida (156 isolates), Cryptococcus (60), Kloeckera (46), Rhodotorula (63), Sporobolomyces (1), Torulopsis (75) and Trichosporon (2). No sporogenous basidiomycetous yeasts were identified. Numbers of yeasts isolated varied seasonally for both PC and NC bees, increasing in March-April, September-October and in December for PC bees. Maximum numbers for NC bees was July-September which coincided with minimum isolates from PC bees (June-August). Isolation of sporogenous and asporogenous yeasts also varied with time of year and/or type of bee activity. KEYWORDS Yeasts;, honey bees;, yeast ecology;, insect ecology.