(n.) One of the spores contained in the asci of lichens and fungi. [See Illust. of Ascus.]
Example Sentences:
(1) To isolate single spores from adhesive ascospores and the mycelium, the suspension was sucked through a combination of sintered-glass plates with different pore sizes.
(2) (2) Coincident disomy increased as a function of the mean number of disomic chromosomes per spore in each dyad, but this increase differed functionally from that expected if coincident disomy in the two ascospores were a simple, meiotically independent, concomitant of multiple disomy.
(3) Fungi of the class Pyrenomycetes (Ascomycotina) form a morphological series ranging from those that shoot ascospores (sexual spores) forcibly from the ascus (spore sac) to fungi that ooze ascospores or have no obvious mechanism for ascospore release.
(4) SPR6 is inessential for sporulation; mutants that lack SPR6 activity sporulate normally and produce viable ascospores.
(5) Complementation tests defined two new genetic loci (spo19 and spo20) essential for ascospore formation, in addition to the 18 known spo loci (Bresch et al.
(6) The results obtained demonstrate that the REC46 gene product modulates mitotic chromosomal stability and recombination and is essential for sporulation (meiosis and ascospore formation).
(7) The mutual attraction of conidia to protoperithecia of the opposite mating type was studied genetically in crosses where a mixture of conidia from two different strains, one of which was marked by an ascospore color mutant gene tan spore (ts), was applied to protoperithecia.
(8) Trehalose is located in the cytoplasm, whereas trehalase resides within the protein and carbohydrate matrix of the innermost major cell wall layer of the ascospore.
(9) Strains of Yarrowia lipolytica forming exclusively spherical ascospores were developed through inbreeding.
(10) The production of diploid ascospores in these strains is apparently under polygenic control.
(11) Electrophoretic measurements on Saccharomyces cerevisiae ascospores indicated the presence of a surface protein layer which can be removed by papain, chymotrypsin or 8 m urea.
(12) Electrophoretic analysis of fruiting body extracts from Neurospora reveals a characteristic protein, apparently absent in vegetative structures and ascospores, and which increases markedly in relative concentration after fertilization.
(13) Due to the characteristic shape of the ascus and ascospores, T. burgeffiana is to be considered a synonym of M. pulcherrima.
(14) The segregation pattern of this character obtained by random spore analysis of the ascospores derived from the cross of the two strains strongly suggests that the resistance to tetracycline is under mitochondrial control.
(15) Potassium sorbate, sodium benzoate, sulfur dioxide, and diethylpyrocarbonate (DEPC) were tested for their effectiveness in preventing the outgrowth of Byssochlamys nivea Westling ascospores.
(16) In this case germination of the binucleate ascospore is not preceded by a mitosis.
(17) Transcripts for four of the genes were detected in all three spore types; mRNA for the fifth gene was detected in macroconidia and microconidia but not in ascospores.
(18) Further implications of this study suggest the importance of extensive ascospore analysis when investigating the perfect states of fungi in order to avoid creating unwarranted new species.
(19) The species forming asci from conjugating gametangial cells and having ellipsoidal ascospores are transferred to Dipodascus.
(20) Development of the ascospores of Sporopachydermia lactativora and S. cereana was studied in ultrathin sections.
Oospore
Definition:
(n.) A special kind of spore resulting from the fertilization of an oosphere by antherozoids.
(n.) A fertilized oosphere in the ovule of a flowering plant.
Example Sentences:
(1) Encapsulated sexual stages (oospores), held at 23-26 degrees C for up to 35 days or frozen for 8-10 days, were infective to mosquito larvae for up to 48 days after immersion in water and during that time over 50% of the oospores germinated.
(2) Enrichment of the phospholipid fraction of total cell lipid of P. ultimum with unsaturated fatty acids promoted oospore induction, and enhanced levels of unsaturated fatty acids in the neutral lipid fraction increased oospore viability.
(3) The rates of development of Lagenidium giganteum were determined in the four larval instars of Culex quinquefasciatus Say held at 15, 20, 25, 27, 30, and 34 degrees C. The fastest development was in second instars held at 34 degrees; vesicles and oospores occurred in 50% of the larvae (the median development time) 19.7 and 25.0 h, respectively, after infection.
(4) The greatest median time to the formation of vesicles was in third instars at 15 degrees C (185.6 h) and for oospores was in second instars at 15 degrees C (152.3 h).
(5) The fungus did not form oospores in fourth instars at 15 degrees C. The median developmental rates of vesicles and oospores in each instar were fit to the Sharpe & DeMichele model, which may be used to predict the effects of different temperatures on the in-vivo developmental rate of the fungus.
(6) For some pythiaceous fungi, the levels of sterols required for the maturation of oospores with appropriate phospholipid medium supplementation suggest that these compounds are necessary only for the sparking and critical domain roles previously described in other fungi.
(7) The antheridial protoplast migrates through a pore in the adjacent wall and fuses with the oogonial protoplast to produce a thick-walled reticulate oospore.
(8) quinquefasciatus at 6-7 days after treatment while encapsulated oospores gave 100% control at 11 days posttreatment.
(9) The formation of oogonia, antheridia, and oospores also occurred.
(10) Oospores which were desiccated in the field following application provided consistently high larval infection levels after reflooding of the fields.
(11) aphanidermatum and P. myriotylum grew from mycelium on GAM, but their oospores did not germinate nor could they be isolated from soilon this medium.
(12) This species produces echinulate, spherical oospores.
(13) The fungus is rapidly cleared from mice following intraperitoneal injection of large quantities of mycelium and oospores.
(14) Induction and maturation of the sexual stage (oospores) of the facultative mosquito parasite Lagenidium giganteum (Oomycetes: Lagenidiales) are complex developmental processes regulated by calcium-dependent events.
(15) Enrichment of the polar and neutral lipid fractions of the LGCA and LGBS strains with unsaturated fatty acids promoted oospore induction, and increased oospore viability.
(16) A calcium chelator (EGTA), an ionophore (chlortetracycline), and inhibitors of the calcium-binding protein calmodulin (dibucaine, trifluoperazine, chlorpromazine) disrupted several discrete developmental steps associated with oosporogenesis: induction of antheridia, gametangial fusion, meiosis, oospore wall formation, and subsequent spore maturation.
(17) P. oligandrum oospores germinated abundantly when host species were present.
(18) A third isolate of this mosquito pathogen, the North Carolina strain (LGNC), requires sterols plus phospholipids to produce oospores in vitro.
(19) The requirement for an exogenous source of sterols for sexual reproduction by several members of the Pythiaceae has been questioned by reports of apparent induction and maturation of oospores on defined media supplemented with phospholipids in the absence of sterols.
(20) Using developmentally synchronized cultures of Lagenidium giganteum (Oomycetes: Lagenidiales), a facultative parasite of mosquito larvae, it has been documented that oxidative lipid metabolism is necessary for the induction and subsequent maturation of its sexual stage, the oospore.