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121.
JOSÉ COLA ZANUNCIO MÁBIO CHRYSLEY LACERDA JOSÉ SALAZAR ZANUNCIO JUNIOR TERESINHA VINHA ZANUNCIO ANA MARIA CAMÊLO DA SILVA MARCELO CURITIBA ESPINDULA 《The Annals of applied biology》2004,144(3):357-361
The reproductive potential and population growth (rm and λ) of the predator Supputius cincticeps (Heteroptera: Pentatomidae) were evaluated using a life and fertility table. S. cincticeps was reared on one plant of Eucalyptus cloeziana in the field and fed with Tenebrio molitor (Coleoptera: Tenebrionidae) pupae. Females of this predator had a net reproductive rate (R0) of 21.02 females/female; an intrinsic rate of population increase (rm) of 0.041 and finite rate of increase (λ) of 1.042. This resulted in population growth of S. cincticeps in the eucalyptus plant with a doubling time of 17.01 days. This natural enemy can be reared under field conditions with alternative prey for use in biological control. Such individuals of S. cinticeps will be better adapted to field conditions when they are liberated. 相似文献
122.
1.按照Casals氏醋酮乙醚浸渍法制乙型脑炎病毒抗原过程中,将病毒鼠脑组几重复以生理鹽水浸渍制作抗原。
2.经第2次浸出的抗原舆初次浸出者分别做補髓结合试验,结果在效价上无顯著的差刖亦无抗補體的理象的发生。
3.此种第2次漫出抗原,在抗原敏感性测定及抗原特異性的的试验,均初步证明可供宝際補體结合试验的应用。因而在不增加成本及复稚步骤条件下,可加倍抗原的产量供应。 相似文献
123.
Competition for water availability was studied in a mixed natural stand of Quercus suber L. and Quercus cerris L. growing in Sicily by measuring diurnal changes of leaf conductance to water vapour ( g L ), water potential ( Ψ L ) and relative water content ( RWC ) in April, July and October 1997 as well as the seasonal changes in root hydraulic conductance per unit leaf surface area ( K RL ). Quercus cerris behaved as a drought-tolerant species, with strong reductions of K RL , Ψ L , and RWC in the summer. By contrast, Q. suber appeared to withstand summer drought by an avoidance strategy based on reducing g L , maintaining Ψ L and RWC high and K RL at the same level as that measured in the spring. A 'conductance ratio' ( CR ) was calculated in terms of the ratio of g L to K RL . Seasonal changes of this ratio contrasted in the two species, thus suggesting that Q. suber and Q. cerris did not really compete for available water. In the summer, when Q. suber was extracting water from the soil to maintain high leaf hydration, Q. cerris had restricted water absorption, thus suffering drought but tolerating its effects. The possibility that cohabitation of drought-tolerant with drought-avoiding species can be generalized is also discussed. 相似文献
124.
Leaf internal diffusion conductance limits photosynthesis more strongly in older leaves of Mediterranean evergreen broad-leaved species 总被引:11,自引:1,他引:11
ÜLO NIINEMETS ALESSANDRO CESCATTI MIRCO RODEGHIERO & TIINA TOSENS 《Plant, cell & environment》2005,28(12):1552-1566
Leaf age-dependent changes in structure, nitrogen content, internal mesophyll diffusion conductance (gm), the capacity for photosynthetic electron transport (Jmax) and the maximum carboxylase activity of Rubisco (Vcmax) were investigated in mature non-senescent leaves of Laurus nobilis L., Olea europea L. and Quercus ilex L. to test the hypothesis that the relative significance of biochemical and diffusion limitations of photosynthesis changes with leaf age. The leaf life-span was up to 3 years in L. nobilis and O. europea and 6 years in Q. ilex. Increases in leaf age resulted in enhanced leaf dry mass per unit area (MA), larger leaf dry to fresh mass ratio, and lower nitrogen contents per dry mass (NM) in all species, and lower nitrogen contents per area (NA) in L. nobilis and Q. ilex. Older leaves had lower gm, Jmax and Vcmax. Due to the age-dependent increase in MA, mass-based gm, Jmax and Vcmax declined more strongly (7- to 10-fold) with age than area-based (5- to 7-fold) characteristics. Diffusion conductance was positively associated with foliage photosynthetic potentials. However, this correlation was curvilinear, leading to lower ratio of chloroplastic to internal CO2 concentration (Cc/Ci) and larger drawdown of CO2 from leaf internal air space to chloroplasts (ΔC) in older leaves with lower gm. Overall the age-dependent decreases in photosynthetic potentials were associated with decreases in NM and in the fraction of N in photosynthetic proteins, whereas decreases in gm were associated with increases in MA and the fraction of cell walls. These age-dependent modifications altered the functional scaling of foliage photosynthetic potentials with MA, NM, and NA. The species primarily differed in the rate of age-dependent modifications in foliage structural and functional characteristics, but also in the degree of age-dependent changes in various variables. Stomatal openness was weakly associated with leaf age, but due to species differences in stomatal openness, the distribution of total diffusion limitation between stomata and mesophyll varied among species. These data collectively demonstrate that in Mediterranean evergreens, structural limitations of photosynthesis strongly interact with biochemical limitations. Age-dependent changes in gm and photosynthetic capacities do not occur in a co-ordinated manner in these species such that mesophyll diffusion constraints curb photosynthesis more in older than in younger leaves. 相似文献
125.
126.
PATRIZIA TRIFILÒ FABIO RAIMONDO MARIA A. LO GULLO PIERA M. BARBERA SEBASTIANO SALLEO ANDREA NARDINI 《Plant, cell & environment》2014,37(11):2491-2499
Diurnal changes in percentage loss of hydraulic conductivity (PLC), with recorded values being higher at midday than on the following morning, have been interpreted as evidence for the occurrence of cycles of xylem conduits' embolism and repair. Recent reports have suggested that diurnal PLC changes might arise as a consequence of an experimental artefact, that is, air entry into xylem conduits upon cutting stems, even if under water, while under substantial tension generated by transpiration. Rehydration procedures prior to hydraulic measurements have been recommended to avoid this artefact. In the present study, we show that xylem rehydration prior to hydraulic measurements might favour xylem refilling and embolism repair, thus leading to PLC values erroneously lower than those actually experienced by transpiring plants. When xylem tension relaxation procedures were performed on stems where refilling mechanisms had been previously inhibited by mechanical (girdling) or chemical (orthovanadate) treatment, PLC values measured in stems cut under native tension were the same as those measured after sample rehydration/relaxation. Our data call for renewed attention to the procedures of sample collection in the field and transport to the laboratory, and suggest that girdling might be a recommendable treatment prior to sample collection for PLC measurements. 相似文献
127.
Crimson red snapper (Lutjanus erythropterus) is an important marine foodfish species in Asia with great potentials for aquaculture. We isolated nine polymorphic microsatellites, among which eight were tetranucleotide repeats, and one was CA‐microsatellite. The average allele number present in 48 individuals was 11.1/locus, ranging from three to 33. The expected heterozygosity ranged from 0.49 to 0.97 with an average of 0.74. Six of the nine markers conformed to the Hardy–Weinberg expectations. No pairwise markers showed the possibility of linkage. Protocols for two multiplex polymerase chain reactions (PCRs), each amplifying two and seven markers, respectively, were presented. The developed microsatellites and optimized multiplex PCRs will be useful for studying population structure of wild stocks and parentage assignment for cultured populations. 相似文献
128.
129.
GLENN YANNIC LOÏC PELLISSIER SYLVAIN DUBEY RODRIGO VEGA PATRICK BASSET STEFANO MAZZOTTI ELENA PECCHIOLI CRISTIANO VERNESI HEIDI C. HAUFFE JEREMY B. SEARLE JACQUES HAUSSER 《Biological journal of the Linnean Society. Linnean Society of London》2012,105(4):864-880
The aim of the present study was to investigate the genetic structure of the Valais shrew (Sorex antinorii) by a combined phylogeographical and landscape genetic approach, and thereby to infer the locations of glacial refugia and establish the influence of geographical barriers. We sequenced part of the mitochondrial cytochrome b (cyt b) gene of 179 individuals of S. antinorii sampled across the entire species' range. Six specimens attributed to S. arunchi were included in the analysis. The phylogeographical pattern was assessed by Bayesian molecular phylogenetic reconstruction, population genetic analyses, and a species distribution modelling (SDM)‐based hindcasting approach. We also used landscape genetics (including isolation‐by‐resistance) to infer the determinants of current intra‐specific genetic structure. The phylogeographical analysis revealed shallow divergence among haplotypes and no clear substructure within S. antinorii. The starlike structure of the median‐joining network is consistent with population expansion from a single refugium, probably located in the Apennines. Long branches observed on the same network also suggest that another refugium may have existed in the north‐eastern part of Italy. This result is consistent with SDM, which also suggests several habitable areas for S. antinorii in the Italian peninsula during the LGM. Therefore S. antinorii appears to have occupied disconnected glacial refugia in the Italian peninsula, supporting previous data for other species showing multiple refugia within southern refugial areas. By coupling genetic analyses and SDM, we were able to infer how past climatic suitability contributed to genetic divergence of populations. The genetic differentiation shown in the present study does not support the specific status of S. arunchi. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 105 , 864–880. 相似文献
130.
We report measurements of the number of vessels ending withinthe nodes in comparison with that in the internodes Such measurementshave been carried out during autumn 1982 and 1983 in 1-year-oldtwigs of three species with diffuse-porous wood (Vitis vintferaL. Populus deitoides Bartr and Olea europaea L) and three ring-poroustrees (Juglans nigra L, Castanea sativa Mill, Sophora JaponicaL) In all three species with diffuse-porous wood, a significantlyhigher percentage of vessels ending in the nodes (at the leafgap) was recorded when compared with that in the internodesNo significant differences were found between nodes and internodesin this respect in ring-porous trees. Since vessel ends arecapable of screening out gaseous emboli and/or particles biggerthan 1 µm in diameter, we interpret the nodes of diffuse-poroustrees as stem zones providing safety for the water conductingsystem .The reason why ring-porous trees are likely not to needsuch safety zones is also discussed Vitis vinifera L, grapevine, Populus deltoides Bartr, poplar, Olea europaea L, olive, Juglans nigra L, Eastern black walnut, Castanea sativa Mill, European chestnut, Sophora japonica L, Japanese pagoda tree, vessel ends, nodes, internodes 相似文献