The relationship between supercooling and survival of the beech leaf mining weevil,
Rhynchaenus fagi was examined in exposures at constant temperatures between +10 and −15 °C, and in cycling regimes. ...Similar observations were made on naturally overwintering field populations.
No weevil survived cooling to, or below the supercooling point. The mean supercooling point of weevils exposed to temperatures at, or below +2 °C, or sampled from the field, was consistently below −21 °C. When exposed to a constant +2 or −5 °C, mortality was low, at 10 and 12% after 168 and 126 days respectively. Mortality increased rapidly in weevils exposed to temperatures below −10 °C, with 48% survival after 112 days at −10 °C and only 25% after 84 days at −15 °C. None of the dead weevils had frozen. Periods spent at +2 °C in cycling treatments which included exposure at −10 or −15 °C, extended the duration of survival at the lower temperatures compared to constant exposures at these temperatures, but mortality was still more rapid than at a constant +2 °C. Survival of naturally overwintering insects was consistently high over three winters.
La Slobozia colectiviștii studiază agrozootehnia; La Moroeni a fost inaugurat și dat în folosință un bloc operator; În locul fostului cazino Sinaia s-a deschis un restaurant. Expoziție culinară în ...cadrul restaurantului; Inaugurarea patinoarului Floreasca
Abstracts in Polish. Taxa in Latin
Bibliogr.: p. 180
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Bibliogr. s. 180
Streszcz. ang. i pol. Nazwy taksonów również łac
W nagłówku nad ...tytułem artykułu błędna numeracja: vol. 54 (1)
Two morphologically similar groups of ascomycetes with globose to subglobose perithecia, elongate necks, unitunicate asci floating freely at maturity, and hyaline ascospores currently placed in
...Calosphaeria s. lat. and
Ceratostomella s. lat., respectively, are studied. The
Calosphaeria-like fungi have groups of perithecia growing between cortex and wood, arranged in circular groups with converging necks and piercing the cortex in a common point; the asci with a shallow apical ring and U- to horseshoe-shaped hyaline ascospores are compared with
Calosphaeria pulchella, the type species of the genus. Conidiogenesis of the investigated
Calosphaeria-like fungi is holoblastic-denticulate; ramichloridium-like and sporothrix-like conidiophores and conidia were formed
in vitro. Ascospore and ascus morphology, structure of the ascal apex, ascogenous system, mode of conidiogenesis and the large subunit rRNA sequences of this group differ considerably from
C. pulchella and both groups are unrelated. Thus a new genus,
Tectonidula, is described with two accepted species,
T. hippocrepida and
T. fagi; they are separated by ascospore and ascus morphology and holoblastic-denticulate conidiogenesis from the core species of
Calosphaeria. The placement of
Tectonidula among perithecial ascomycetes is discussed. The relationship of
Tectonidula with
Barbatosphaeria and two ramichloridium-like hyphomycetous genera
Rhodoveronaea and
Myrmecridium is investigated. Three species formerly attributed to
Ceratostomella are studied. The revision of the herbarium type specimen and fresh material of
Ceratostomella ligneola revealed that it is conspecific with
Ceratostomella ampullasca and
Ceratostomella similis. The LSU phylogeny clearly separated
C. ligneola from
Ceratostomella s. str. and morphologically similar
Lentomitella. On the basis of molecular sequence data and detailed comparison of morphology of asci, ascospores and ascogenous system the genus
Natantiella is described for
C. ligneola with
C. ampullasca and
C. similis as its synonyms.
Natantiella produced sterile mycelium
in vitro.
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