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Light initiated fruit body primordia of Coprinus congregatus Bull, ex Fr. grown at relatively high temperature (25°C) require a single dark period or low-temperature induction for completion of fruit-body development. The dark period requirement varied with the temperature regime during the inductive dark period A minimum requirement of 2.5 h was found al 15–20°C. Darkness always promotes development of fruit-body primordial, but cannot, be regarded as an absolute necessity until temperature exceeds about 17.5°C. Normal development of me primordia without darkness was obtained by lowering the temperature to 10°C for 6 h. It appeared that at high temperatures two successive stimuli were required for basidiocarp maturation, a light-off and a subsequent signal light-on signal. On the contrary, at 10°C a single low-temperature signal seemed to be involved. Thus, induction of fruit-body development could be produced by alternative pathways. These developmental features have been extended to other fungi and compared with the flowering processes of some short-day plants. 相似文献
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YONG M.; GUTIERREZ A.; PERERA G.; DURAND P.; POINTIER J.P. 《Journal of Molluscan Studies》2001,67(1):103-112
Conchological, anatomical and genetic characteristics werecompared
among several populations of the Biomphalaria havanensis
complexfrom Cuba and other localities in the Caribbean region. Two
morphometricmeasures (height and diameter) distinguished two closely
similarmorphs of the shell. The reproductive system also separated
thesemorphs, particularly upon comparison of sizes of the penis
sheathand the preputium. The two morphological groups differed in9
to 12 fixed alleles according to population. Further allozymicdata
analyzed in the present work confirmed this difference.The results
strongly support the assumption that the B. havanensis
complexincludes two distinct species: B. havanensis, for
which thetype locality is the swampy area near the vicinity of
Havana,Cuba and Biomphalaria sp. a species which commonly
occurs inCuba and in Dominican Republic. The taxonomic identity of
Biomphalariasp. is discussed. (Received 28 January 2000; accepted 15 August 2000) 相似文献
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CAROLINE MÜLLER ALISON BARKER JEAN-LUC BOEVÉ PETER W. DE JONG HELENE DE VOS PAUL M. BRAKEFIELD 《Biological journal of the Linnean Society. Linnean Society of London》2004,83(2):219-227
This study compares the population genetic structure of two obligate parthenogenetic sawfly species, Aneugmenus padi (L.) Zhelochovtsev and Eurhadinoceraea ventralis (Panzer) Enslin (Hymenoptera: Tenthredinidae). Allozymes were used to detect genetic differences in larvae collected at different sites in six European countries. For A. padi , scoring six polymorphic enzymes revealed the existence of five dominant, widely distributed clones and several more with only very few individuals occurring locally. The clonal diversity and identity differed across collection sites, with up to at maximum eight clones coexisting at a single locality. In contrast, in E. ventralis , individuals from different localities were all monomorphic for at least six different enzymes and are therefore assumed to belong to the same clone. Differences in population genetic structure of these sawfly species can be related to the differing distributions of their host plants: the fern, Pteridium aquilinum , the host of A. padi , has been an invasive species for more than two hundred years. Spread of clones of A. padi is likely to have closely followed the complex invasive pattern of spread of the plant. Larvae of E. ventralis were collected from local, horticultural plantings of Clematis spp. of recent origin probably with gardeners having traded plants infested with the sawfly. © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 83 , 219–227. 相似文献
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DURAND P 《Annales de l'Institut Pasteur》1950,79(5):579-590
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LYDIE CHAPUIS-LARDY NICOLE WRAGE† AURÉLIE METAY‡ JEAN-LUC CHOTTE§ MARTIAL BERNOUX§ 《Global Change Biology》2007,13(1):1-17
Soils are the main sources of the greenhouse gas nitrous oxide (N2 O). The N2 O emission at the soil surface is the result of production and consumption processes. So far, research has concentrated on net N2 O production. However, in the literature, there are numerous reports of net negative fluxes of N2 O, (i.e. fluxes from the atmosphere to the soil). Such fluxes are frequent and substantial and cannot simply be dismissed as experimental noise.
Net N2 O consumption has been measured under various conditions from the tropics to temperate areas, in natural and agricultural systems. Low mineral N and large moisture contents have sometimes been found to favour N2 O consumption. This fits in with denitrification as the responsible process, reducing N2 O to N2 . However, it has also been reported that nitrifiers consume N2 O in nitrifier denitrification. A contribution of various processes could explain the wide range of conditions found to allow N2 O consumption, ranging from low to high temperatures, wet to dry soils, and fertilized to unfertilized plots. Generally, conditions interfering with N2 O diffusion in the soil seem to enhance N2 O consumption. However, the factors regulating N2 O consumption are not yet well understood and merit further study.
Frequent literature reports of net N2 O consumption suggest that a soil sink could help account for the current imbalance in estimated global budgets of N2 O. Therefore, a systematic investigation into N2 O consumption is necessary. This should concentrate on the organisms, reactions, and environmental factors involved. 相似文献
Net N
Frequent literature reports of net N
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Bayesian clustering algorithms ascertaining spatial population structure: a new computer program and a comparison study 总被引:1,自引:0,他引:1
CHIBIAO CHEN ERIC DURAND FLORENCE FORBES OLIVIER FRANOIS 《Molecular ecology resources》2007,7(5):747-756
On the basis of simulated data, this study compares the relative performances of the Bayesian clustering computer programs structure , geneland , geneclust and a new program named tess . While these four programs can detect population genetic structure from multilocus genotypes, only the last three ones include simultaneous analysis from geographical data. The programs are compared with respect to their abilities to infer the number of populations, to estimate membership probabilities, and to detect genetic discontinuities and clinal variation. The results suggest that combining analyses using tess and structure offers a convenient way to address inference of spatial population structure. 相似文献