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1.
The damselflyMnais pruinosa costalis (Odonata: Calopterygidae) is unusual in that males are dimorphic, existing as clear-winged non-territorial ‘sneaks’ and orange-winged
territorial ‘fighters’. Here we report the results of population census data and behavioural observations in the field and
laboratory, and present estimates of emergence period, reproductive period, total lifespan, and reproductive success of each
morph. Clear-winged males are smaller and have lower daily reproductive success than orange-winged males, but live for longer
in the field and laboratory. We accounted for the difference in the ‘operational reproductive life’ of the two morphs and
estimated lifetime reproductive success: there was no difference between clear-winged and orange-winged males. We discuss
possible mechanisms for the maintenance of the two forms. 相似文献
2.
Zhentu Ying Thomas L. Davenport Taifang Zhang Raymond J. Schnell Cecile L. Tondo 《Plant Molecular Biology Reporter》2009,27(3):374-380
‘Hass’ is the most popular avocado (Persea americana Mill.) cultivar in the world. It has been characterized as a crop requiring cross-pollination. However, the potential extent
of self-pollination and the most effective pollen donors (best cross-pollinizing cultivars) have not been determined. In this
study, 56 markers were screened against ‘Hass’ and nine commonly used pollinizing cultivars grown in southern California:
‘Bacon,’ ‘Ettinger,’ ‘Fuerte,’ ‘Harvest,’ ‘Lamb Hass,’ ‘Marvel,’ ‘Nobel,’ ‘Sir Prize,’ and ‘Zutano.’ Seventeen microsatellite,
i.e., simple sequence repeat (SSR) markers, were found to be very promising for paternity analysis. Four highly informative
SSR markers were selected to accurately and unequivocally identify pollen parents of ‘Hass’ fruit from an orchard interplanted
with these pollinizing cultivars. From 2003 to 2006, 7,984 ‘Hass’ fruit were analyzed for their paternity. Overall, the pollen
parents of 99.55% of the analyzed fruit could be unequivocally identified with a single multiplex polymerase chain reaction
(PCR). Only 36 fruits (<0.45%) required a second PCR reaction to reach unequivocal identification of the pollen parents. 相似文献
3.
Mustapha Ennajeh Ahmadou Mohamed Vadel Habib Khemira 《Acta Physiologiae Plantarum》2009,31(4):711-721
In this study, we compared the efficacy of defense mechanisms against severe water deficit in the leaves of two olive (Olea europaea L.) cultivars, ‘Chemlali’ and ‘Meski’, reputed drought resistant and drought sensitive, respectively. Two-year old plants
growing in sand filled 10-dm3 pots were not watered for 2 months. Changes in chlorophyll fluorescence parameters and malondialdehyde content as leaf relative
water content (RWC) decreased showed that ‘Chemlali’ was able to maintain functional and structural cell integrity longer
than ‘Meski’. Mannitol started to accumulate later in the leaves of ‘Chemlali’ but reached higher levels than in the leaves
of ‘Meski’. The latter accumulated several soluble sugars at lower dehydration. ‘Chemlali’ leaves also accumulated larger
quantities of phenolic compounds which can improve its antioxidant response. Furthermore, the activity of three antioxidant
enzymes catalase (CAT), peroxidase (POD) and ascorbate peroxidase (APX) increased as leaf RWC decreased. However, differences
were observed between the two cultivars for CAT and POD but not for APX. The activity of the first two enzymes increased earlier
in ‘Meski’, but reached higher levels in ‘Chemlali’. At low leaf hydration levels, ‘Chemlali’ leaves accumulated mannitol
and phenolic compounds and had increased CAT and POD activities. These observations suggest that ‘Chemlali’ was more capable
of maintaining its leaf cell integrity under severe water stress because of more efficient osmoprotection and antioxidation
mechanisms. 相似文献
4.
Heat waves are expected to increase in frequency and magnitude with climate change. The first part of a study to produce projections
of the effect of future climate change on heat-related mortality is presented. Separate city-specific empirical statistical
models that quantify significant relationships between summer daily maximum temperature (T
max) and daily heat-related deaths are constructed from historical data for six cities: Boston, Budapest, Dallas, Lisbon, London,
and Sydney. ‘Threshold temperatures’ above which heat-related deaths begin to occur are identified. The results demonstrate
significantly lower thresholds in ‘cooler’ cities exhibiting lower mean summer temperatures than in ‘warmer’ cities exhibiting
higher mean summer temperatures. Analysis of individual ‘heat waves’ illustrates that a greater proportion of mortality is
due to mortality displacement in cities with less sensitive temperature–mortality relationships than in those with more sensitive
relationships, and that mortality displacement is no longer a feature more than 12 days after the end of the heat wave. Validation
techniques through residual and correlation analyses of modelled and observed values and comparisons with other studies indicate
that the observed temperature–mortality relationships are represented well by each of the models. The models can therefore
be used with confidence to examine future heat-related deaths under various climate change scenarios for the respective cities
(presented in Part 2). 相似文献
5.
Four new and one unidentified species of Neohaliotrema Yamaguti, 1965 were obtained from the gills of the Indo-Pacific sergeant Abudefduf vaigensis (Quoy & Gaimard) off Pulau Langkawi, Malaysia. The five species, N. malayense n. sp., N. bombini n. sp., N. andamanense n. sp., N. parvum n. sp. and an unidentified Neohaliotrema sp. (similar to N. macracanthum Zhukov, 1976), are described and distinguished based mainly on features of the haptor. Species of this genus are divisible
into two groups, the ‘maomao group’, with two pairs of morphometrically modified ‘marginal’ hooks and a fenestrated haptor,
and the ‘gracile group’, with morphologically similar marginal hooks and an entire haptor. With the exception of N. bombini n. sp., the species described fit within the ‘maomao group’. It is suggested that the more complex Neohaliotrema species of the ‘maomao group’ have modified hooks 1 and 2 on a haptoral ‘isthmus’ between two large apertures, i.e. ‘windows’,
whereas the less complex species lacking these features are those of the ‘gracile group’. Neohaliotrema spp. have only a single pair of pigmented eye-spots. A fenestrated haptor is unique to the Neohaliotrema spp. of the ‘maomao group’. The generic diagnosis of Neohaliotrema is amended to include new data and a key to its known species is presented. 相似文献
6.
Shimpei Uraguchi Masako Kiyono Takuya Sakamoto Izumi Watanabe Katsuji Kuno 《Planta》2009,230(2):267-276
The contributions of cadmium (Cd) accumulation in cell walls, antioxidative enzymes and induction of phytochelatins (PCs)
to Cd tolerance were investigated in two distinctive genotypes of black oat (Avena strigosa Schreb.). One cultivar of black oat ‘New oat’ accumulated Cd in the leaves at the highest concentration compared to another
black oat cultivar ‘Soil saver’ and other major graminaceous crops. The shoot:root Cd ratio also demonstrated that ‘New oat’
was the high Cd-accumulating cultivar, whereas ‘Soil saver’ was the low Cd-accumulating cultivar. Varied levels of Cd exposure
demonstrated the strong Cd tolerance of ‘New oat’. By contrast, low Cd-accumulating cultivar ‘Soil saver’ suffered Cd toxicity
such as growth defects and increased lipid peroxidation, even though it accumulated less Cd in shoots than ‘New oat’. Higher
activities of ascorbate peroxidase (EC 1.11.1.11) and superoxide dismutase (EC 1. 15. 1. 1) were observed in the leaves of
‘New oat’ than in ‘Soil saver’. No advantage of ‘New oat’ in PCs induction was observed in comparison to Cd-sensitive cultivar
‘Soil saver’, although Cd exposure increased the concentration of total PCs in both cultivars. Higher and increased Cd accumulation
in cell wall fraction was observed in shoots of ‘New oat’. On the other hand, in ‘Soil saver’, apoplasmic Cd accumulation
showed saturation under higher Cd exposure. Overall, the present results suggest that cell wall Cd accumulation and antioxidative
activities function in the tolerance against Cd stress possibly in combination with vacuolar Cd compartmentation. 相似文献
7.
Ying Li Yuping Song Gongjun Shi Jianjun Wang Xilin Hou 《Acta Physiologiae Plantarum》2009,31(1):155-162
Changes in ascorbic acid content and antioxidant enzyme activities were investigated in non-heading Chinese cabbage (Brassica campestris ssp. chinensis Makino) leaves of ‘Wutacai’ and ‘Erqing’ exposed to excess copper (Cu). Cu treatment reduced the fresh weight of shoot and
root by 57% and 46% in ‘Wutacai’, and 60 and 54% in ‘Erqing’, respectively. The accumulation of copper in leaves was higher
in ‘Wutacai’ than that in ‘Erqing’. Compared to the control, ascorbic acid (AsA) contents were significantly decreased after
copper treatment in both cultivars, while they were higher in ‘Wutacai’ than in ‘Erqing’, which may explain the higher copper-tolerance
of ‘Wutacai’ with higher copper accumulation. The higher AsA contents of ‘Wutacai’ resulted from their lower activities of
degrading enzymes, such as ascorbate oxydase (AAO) and ascorbate peroxidase (APX), as well as the increasing activity of dehydroascorbate
reductase (DHAR) after copper treatment compared with ‘Erqing’. Copper stimulated superoxide dismutase (SOD) activity in both
cultivars, but for catalase (CAT), there was little difference between both cultivars. Peroxidases (POD) activity was decreased
after copper treatment in ‘Erqing’, while in ‘Wutacai’, it was significantly increased at 14 days, and POD activity was higher
in ‘Wutacai’ than that in ‘Erqing’ at 21 and 28 days. Therefore, the induced increasing activity of POD in ‘Wutacai’ also
played an important role in its copper tolerance. 相似文献
8.
Litz R.E. Hendrix R.C. Moon P.A. Chavez V. M. 《Plant Cell, Tissue and Organ Culture》1998,53(1):13-18
The nucellus was removed from immature seeds of 4 mango genotypes, andcultured under different induction conditions. The mango
genotypes includedpolyembryonic ‘Hindi’ and ‘Nam Doc Mai’ and monoembryonic ‘Lippens’ and’Tommy Atkins‘. Nucellar explants
were cultured on modified B5 basal mediumunder the following inductive conditions: 1) 4.52 μM 2,4-D; 2) nogrowth regulator
(control); 3) 4.52 μM 2,4-D + embryogenic ‘Parris‘nurse culture; 4) no growth regulator + embryogenic ‘Parris’ nurse culture.Induction
of embryogenic competence was mediated by 4 factors: genotype,explanting, 2,4-D and the presence of a highly embryogenic nurse
culture,although there was considerable difference in genotype response. ‘Hindi’ hadthe greatest embryogenic potential, followed
by ‘Lippens’, ‘Tommy Atkins‘and ‘Nam Doc Mai’, respectively. Induction of embryogenic cultures of allgenotypes at low frequency
occurred as a result of explanting excisednucellus onto control medium. The most effective treatment for inducingembryogenic
cultures was 2,4-D + embryogenic ‘Parris’ nurse culture with’Hindi’, ‘Lippens’ and ‘Nam doc Mai’, with the exception of ‘Tommy
Atkins’,in which the treatment with 2,4-D alone was most effective.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
9.
Monica Santa-Maria Kenneth V. Pecota Craig G. Yencho George Allen Bryon Sosinski 《Plant Cell, Tissue and Organ Culture》2009,97(1):109-117
Sweetpotato (Ipomoea batatas L.) is an important crop in North Carolina with annual production of 0.33 million tons, accounting for 37% of total US supply
(USDA, Louisiana Farm Reporter 8(12), August 2008). To target industrial use, novel high-starch industrial-type varieties that contain more than 30% dry matter were developed
by conventional breeding methods. In vitro cultures from selected genotypes were established using meristem culture. To establish
regeneration procedures that could be coupled with transformation experiments, conditions for the induction of rapid shoot-organogenesis
in leaf explants were compared using varying concentrations of the auxins ‘NAA’, ‘IAA’, ‘2,4-D’, and ‘4-FA’ either alone or
in combination with zeatin riboside. Regeneration efficiencies, defined as the number of explants developing shoots out of
the total number tested, were as high as 57% for the best genotypes, with a significant genotype-dependent response observed
in all the hormone regimes evaluated. In all treatments, shoot regeneration was observed within 2 months. Our results led
to the establishment of optimized in vitro regeneration procedures for the novel high-starch sweetpotato (SP) genotypes ‘DM01-158’,
‘FTA94’, ‘FT489’, and ‘PDM P4’ that are rapid and reliable. 相似文献
10.
11.
Ecology is being introduced to Evolutionary Developmental Biology to enhance organism-, population-, species-, and higher-taxon-level
studies. This exciting, bourgeoning troika will revolutionise how investigators consider relationships among environment,
ontogeny, and phylogeny. Features are studied (and even defined) differently in ecology, development, and evolution. Form
is central to development and evolution but peripheral to ecology. Congruence (i.e., homology) is applied at different hierarchical
levels in the three disciplines. Function is central to ecology but peripheral to development. Herein, the supercategories
form (‘isomorphic’ or ‘allomorphic’), congruence (‘homologous’ or ‘homoplastic’), and function (‘adaptive’ or ‘nonadaptive’)
are combined with two developmental mode (i.e., growth) categories (‘conformational’ or ‘nonconformational’) to provide a
16-class system for analysing features in studies in which ecology, development, and evolution are integrated. 相似文献
12.
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14.
Lijun Chai Xiaoxia Ge Manosh Kumar Biswas Qiang Xu Xiuxin Deng 《Plant Cell, Tissue and Organ Culture》2011,104(1):1-11
‘Shatian’ pummelo (Citrus grandis Osbeck), one of the main citrus cultivars in China, is self-incompatible, and its pollen tubes are believed to be arrested
in style after self-pollination.We have characterized one ‘Shatian’ pummelo mutant, named ‘Zigui shatian’ pummelo. The mutant
pummelo had identical DNA ploidy level, morphology (leaf shape, stoma size and density, pollen shape and size) and developmental
progress of pistil and male organs to that of the common ‘Shatian’ pummelo. However, unlike the common ‘Shatian’ pummelo,
‘Zigui shatian’ is self-compatible since its pollen tubes can self-pollinate allowing for successful fertilization. Histological
analyses of ‘Shatian’ pummelo further verified abnormal post-zygotic development which led to seed abortion. Simple sequence
repeats (SSR) analysis revealed polymorphism in 1 of the 120 primers screened showing that ‘Zigui shatian’ and ‘Shatian’ pummelo
are different at the DNA level. Taken together, these data suggested mutant ‘Zigui shatian’ pummelo might be derived from
‘Shatian’ pummelo with self-sterility by self-incongruity after self-fertilization. 相似文献
15.
Gerald Kastberger Ronald Thenius Anton Stabentheiner Randall Hepburn 《Journal of Insect Behavior》2009,22(1):65-85
Colony defence in Apis mellifera involves a variety of traits ranging from ‘aggressive’ (e.g. entrance guarding, recruitment
of flying guards) to ‘docile’ (e.g. retreating into the nest) expression. We tested 11 colonies of three subspecies (capensis, scutellata, carnica) regarding their defensiveness. Each colony was selected as reportedly ‘aggressive’, ‘intermediate’ or ‘docile’ and consisted
of about 10,000 bees. We applied three stimulation regimes (mechanical disturbance, exposure to alarm pheromones, and the
combination of both) and measured their behaviours by tracking the rates of outflying bees at the entrance sites of the test
hives. We provided evidence that for mechanical disturbances the test colonies resolved into two response types, if the ‘immediate’
defence response, assessed in the first minute of stimulation, was taken as a function of foraging: ‘releaser’ colonies allocated flying guards, ‘retreater’ colonies reduced the outside-hive activities. This division was observed irrespective
of the subspecies membership and maintained in even roughly changing environmental conditions. However, if pheromone and mechanical
stimulation were combined, the variety of colony defensiveness restricted to two further types irrespective of the subspecies
membership: six of nine colonies degraded their rate of flying defenders with increasing foraging level, three of the colonies
extended their ‘aggressiveness’ by increasing the defender rate with the foraging level. Such ‘super-aggressive’ colonies
obviously are able to allocate two separate recruitment pools for foragers and flying defenders. 相似文献
16.
Csaba Lantos Anikó Gémes Juhász György Somogyi Krisztina Ötvös Pál Vági Róbert Mihály Zoltán Kristóf Norbert Somogyi János Pauk 《Plant Cell, Tissue and Organ Culture》2009,97(3):285-293
The influence of the developmental stage of microspores on establishing isolated microspore cultures of three Hungarian (‘Szegedi
80’, ‘Szegedi 178’, and ‘Remény’) and three Spanish (‘Jeromin’, ‘Jariza’, and ‘Jaranda’) pepper genotypes was investigated.
Donor anthers containing 80% uninucleated and 20% binucleated microspores yielded the highest frequency of successful microspore
cultures. Co-cultures with wheat, line ‘CY-45’, ovaries exhibited enhanced frequency of embryoid production than those with
pepper ovaries. Differences in efficiency of isolated pepper microspore culture establishment were observed among different
pepper genotypes. Green plantlets were regenerated from microspore-derived embryoids, but some were exhibited abnormal growth
habits, such as leaf rosetting. A total of seven fertile microspore-derived plants were obtained, including three ‘Jariza’,
three ‘Jaranda’, and a single ‘Szegedi 80’ plant. 相似文献
17.
Monica M. Miazzi Hajaj R. Hajjeh Francesco Faretra 《In vitro cellular & developmental biology. Plant》2010,46(4):363-367
Powdery mildew, caused by the obligate biotrophic ascomycete Erysiphe necator, is one of the most destructive grapevine diseases worldwide. Cultivars of Vitis vinifera L, for wine and table grape production, are all susceptible to E. necator, whose attacks result in severe epidemics under the warm and dry conditions of the Mediterranean basin. The aim of the present
study was to compare the susceptibility of different grapevine cultivars to E. necator by an in vitro assay for assessing the potentiality of this method in breeding programs for resistance to the pathogen. Leaves of 12 grapevine
cultivars were spot-inoculated in vitro with about 10 conidia from five different isolates of E. necator, using colony growth and conidiation 3 wk post-inoculation as indicators of susceptibility to the disease. A remarkable difference
was observed between highly susceptible cultivars like ‘Baresana’, ‘Malvasia’, ‘Bianca’, and ‘Italia’, and the less susceptible
‘Alphonse Lavallée’ and ‘Ohanez’, in accordance with their behavior in the field. No statistically significant differences
were found in the virulence of E. necator isolates. 相似文献
18.
Development of 1,030 genomic SSR markers in switchgrass 总被引:1,自引:0,他引:1
Wang YW Samuels TD Wu YQ 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,122(4):677-686
Switchgrass, Panicum virgatum L., a native to the tall grass prairies in North America, has been grown for soil conservation and herbage production in
the USA and recently widely recognized as a promising dedicated cellulosic bioenergy crop. A large amount of codominant molecular
markers including simple sequence repeats (SSRs) are required for the construction of linkage maps and implementation of molecular
breeding strategies to develop superior switchgrass cultivars. The objectives of this study were (1) to identify SSR-containing
clones and to design PCR primer pairs (PPs) in SSR-enriched genomic libraries, and (2) to validate and characterize the designed
SSR PPs. Five genomic SSR enriched libraries were constructed using genomic DNA of ‘SL93 7 × 15’, a switchgrass genotype selected
in an Oklahoma State University (OSU) southern lowland breeding population. A total of 3,046 clones from four libraries enriched
in (CA/TG)n, (GA/TC)n, (CAG/CTG)n and (AAG/CTT)n SSR repeats were sequenced at the OSU Core Facility. From the sequences,
we isolated 1,300 unique SSR-containing clones, from which we designed 1,398 PPs using SSR Locator V.1 software. Among the
designed PPs, 1,030 (73.7%) amplified reproducible and strong bands with expected fragment size, and 802 detected polymorphic
alleles, in SL93 7 × 15 and ‘NL94 16 × 13’, two parents of one mapping population. All of the four libraries contained a high
rate of perfect SSR repeat types, ranging from 62.7 to 76.2%. Polymorphism of the effective SSR markers was also tested in
two lowland and two upland switchgrass cultivars, encompassing ‘Alamo’ and ‘Kanlow’, and ‘Blackwell’ and ‘Dacotah’, respectively.
The developed SSR markers should be useful in genetic and breeding research in switchgrass. 相似文献
19.
Sundararaju Jothisaraswathi Bakthavachalam Babu Ramasamy Rengasamy 《Journal of applied phycology》2006,18(2):161-166
The alginates extracted from ‘leaf’, ‘stem’ and entire thallus of Turbinaria conoides (J.Ag.) Kütz. were investigated for their viscosity and biochemical constituents namely, β-D-mannuronic acid (M-block}), α-L-guluronic acid (G-Block) and alternating sequences of β–D-mannuronic acid and α-L-guluronic acid (MG-block). Substantial seasonal variation was recorded with high yield of alginate during premonsoon. The yield of alginate was maximum in ‘leaf’ region. In contrast to this, viscosity and G-block were maximum in the ‘stem’ region. A significant positive correlation was observed between viscosity and G-block}. The ratio of guluronic: mannuronic acid was also assessed. Low levels of M/G ratio were recorded in the ‘stem’ region followed by ‘leaf’ and entire thallus. 相似文献
20.
Ewa Hanus-Fajerska Maria Lech Anna Pindel Kazimierz Miczyński 《Acta Physiologiae Plantarum》2000,22(3):317-324
Protocols elaborated with the objective of achieving valuable material for selection procedure of variants with virusresistance
traits in tomato genotypes are presented. Preliminary results are demonstrated in the domain of testing for variability in
somaclones obtained through indirect adventitous organogenesis initiated on leaf explants of cultivated tomato (Lycopersicon esculentum Mill.). Somaclones were grown in greenhouse conditions and variation of their symptoms upon infection with tomato mosaic
(ToMV) or cucumber mosaic (CMV) respectively was observed. Tests for resistance to the local isolates of the above cited viruses
were performed using enzyme linked immunosorbent assay and back inoculation onto diagnostic plants. Screening data are presented.
Desirable variants were selected from cultivars ‘Moneymaker’, ‘Potentat’ and ‘Rutgers’. Some of the ‘Moneymaker’ somaclones
exhibited increased tolerance to cucumber mosaic virus, a few seemed to be even fully resistant though most were susceptible
as donor plants. The most favourable somaclonal lines are actually further tested and monitored for changes in horticultural
characteristics. The described procedure of searching for resistance trait in specific pathogen-free (SPF) plants regenerated
from infected tissue looks promising and thus can serve as aid in attaining appropriate objectives of breeding programme.
Additionaly experiments were initiated to obtain somaclones from cultivars ‘Beta’, ‘Krakus’ and Stevens Rodade hybrid via
regeneration of isolated protoplasts. To this end the callus stage was obtained from all donors. 相似文献