bluuebunny/crossref_metadata_2025 huggingface dataset:
Leaf area development of ABA-deficient and wild-type peas at two levels of nitrogen supply
Authors: Dodd Ian C.
Published: January 2006

The ABA-deficient wilty pea (Pisum sativum L.) and its wild-type (WT) were grown at two levels of nitrogen supply (0.5 and 5.0 mM) for 5–6 weeks from sowing, to determine whether leaf ABA status altered the leaf growth response to N deprivation. Plants were grown at high relative humidity to prevent wilting of the wilty peas. Irrespective of N supply, expanding wilty leaflets had ca 50% less ABA than WT leaflets but similar ethylene evolution rates. Fully expanded wilty leaflets had lower relative water contents (RWC) and were 10–60% smaller in area (according to the node of measurement) than WT leaflets. However, there were no genotypic differences in plant relative leaf expansion rate (RLER). Growth of both genotypes at 0.5 mM N increased the RWC of fully expanded leaflets, but did not alter ethylene evolution or ABA concentration of expanding leaflets. Plants grown at 0.5 mM N showed a 20–30% reduction in RLER, which was similar in magnitude in both wilty and WT peas. Thus,�leaf ABA status did not alter the leaf growth response to N deprivation.
Circadian rhythm of stem and fruit diameter dynamics of Japanesepersimmon (Diospyrus kaki Thunb.) is affected by deficiency of water in saline environments
Authors: Fujita Kounosuke , Ito Junki , Mohapatra Pravat K. , Saneoka Hirofumi , Lee Kei , Kurban Heilil , Kawai Kouji , Ohkura Katsumi
Published: January 2006

Early diagnosis of water deficiency is essential to mitigate salt stress injury in plants. The effects of salt stress during the fruit growth stage on stem and fruit diameters of Japanese persimmon trees (Diospyrus kaki Thunb.) were measured by a micromorphometric technique under greenhouse conditions. This technique is less cumbersome and more precise in comparison to measurement of water potential in a small pressure chamber. The effect of stress was measured on photosynthetic rate, pre-dawn water potential, stomatal conductance, transpiration and Na+ and K+ contents of the stem and leaves. Salt stress was imposed by irrigating the plants with NaCl solution. Stem and fruit diameters of the plants given the control treatment started to decrease around 0600 h and reached a minimum at 1400 h. Salt stress did not change the diurnal pattern of response in stem and fruit diameter dynamics, but decreased the amplitude of the circadian rhythm by influencing both declining and recovery phases. The effect of salt stress on stem diameter appeared after 1 d of treatment, and on the third day in the fruit. Salt stress also reduced water potential, photosynthesis, transpiration and stomatal conductance, and increased concentrations of Na and K in the plant parts. Most of these effects were expressed after a lag period of 5 d of salt application. Utilization of micromorphometric techniques for early diagnosis of water deficiency in salt-prone environments is recommended based on results of this study.
Characterization of the 820-nm transmission signal paralleling the chlorophyll a fluorescence rise (OJIP) in pea leaves
Authors: Schansker Gert , Srivastava Alaka , Govindjee  , Strasser Reto J.
Published: January 2006

Monitoring transmission changes at 820 nm, a measure of the redox states of plastocyanin (PC) and P700, is a good complementary technique for chlorophyll (chl) a fluorescence induction measurements. A thorough characterization of the properties of the 820-nm transmission kinetics during the first second after a dark-to-light transition is provided here for pea (Pisum sativum L.) leaves. The data indicate that plastocyanin in a dark-adapted leaf is in the reduced state. Three photosystem I (PSI)-related components, PC, P700 and ferredoxin, can contribute to the 820-nm transmission signal. The contribution of ferredoxin, however, is only approximately 5%, thus, it can be neglected for further analysis. Here, we show that by monitoring the sequential oxidation of PC and P700 during a far-red pulse and analysing the re-reduction kinetics it is possible to assign the three re-reduction components to PC (τ = 7–14 s) and P700 (τ = 35–55 ms and 1.2–1.6 s). Our data indicate that the faster re-reduction phase (τ =�35–55 ms) may represent a recombination reaction between P700+ and the acceptor side of PSI. This information made it possible to show that the ratio between the potential contributions of PC : P700 is 50 : 50 in pea and Camellia leaves and 40 : 60 in sugar beet leaves.
Mucilage production by wounded xylem tissue of maize roots — time course and stimulus
Authors: Crews Laura J. , McCully Margaret E. , Canny Martin J.
Published: January 2006

As a reaction to invasion by pathogens, plants block their xylem conduits with mucilage, restricting pathogen advance. Wounding soil-grown roots of maize revealed that pectinaceous mucilage could be found in the vessels after 6 h, and abundantly filled most vessels up to 3 cm proximal to the wound after 1 d. Phenolics increased in the mucilage at later times. The same reactions occurred in vessels following mechanical wounding of axenically-grown roots, showing that the presence of microbes is not necessary for the response. The xylem mucilage is similar to root-cap mucilage in mode of extrusion from the periplasmic space of living cells through primary wall, apparent phase transition, and staining indicative of acidic polysaccharides. Whether other known properties of root-cap mucilage which might alter vessel functioning, such as reduction of surface tension and increased viscosity produced by dissolved solutes, are also common to xylem mucilage requires further investigation. However, our results indicate that possible influence of wounding-induced mucilage in xylem vessels should be considered in all experimental investigations of xylem function.
Variable desiccation tolerance in Acer pseudoplatanus seeds in relation to developmental conditions: a case of phenotypic recalcitrance?
Authors: Daws Matthew I. , Cleland Hazel , Chmielarz Pawel , Gorian Fabio , Leprince Olivier , Mullins Christopher E. , Thanos Costas A. , Vandvik Vigdis , Pritchard Hugh W.
Published: January 2006

Nine seedlots of the widely planted southern and central European native tree species Acer pseudoplatanus L. were collected along a north–south gradient spanning 21° of latitude in Europe. We investigated how the heat sum during seed development influences seed maturity as assessed by physical, physiological and biochemical traits. Using principal component analysis we found predictable and consistent patterns in all traits, which correlated with heat sum. For example, compared with fruits from their native range (Italy and France, heat sum >3000°C d), fruits from the coldest location (Scotland; heat sum of 1873°C d) were shorter (c. 30 v. 42 mm), germinated over a narrower temperature range (5–20 v. 5–35°C) and had smaller embryos (28 v. > 70 mg) with a higher water content (c. 63 v. 48%), less negative solute potentials (c. –2.4 v. –4.1 MPa) and were more desiccation sensitive (critical water potential of –20.2 v. –55.4 to –60.7 MPa). The observed level of desiccation-tolerance for the French and Italian seedlots is more consistent with the intermediate category than the previous classification of A. pseudoplatanus as recalcitrant. Our results demonstrate that a lower heat sum causes fruits from northern Europe to be dispersed before maximum potential seed quality is achieved.
Heat-induced oxidative activity protects suspension-cultured plant cells from low temperature damage
Authors: Allan Andrew C. , Maddumage Ratnasiri , Simons Joanne L. , Neill Samuel O. , Ferguson Ian B.
Published: January 2006

A short heat pre-treatment (1 h at 38°C) was found to protect both suspension-cultured apple fruit cells and tobacco cells from cold-induced cell death. Tobacco cells were more sensitive to low temperatures than apple cells, with significant cell death after 48 h at 0 or –2°C. Real-time measurements of H2O2 levels during the heat pre-treatment revealed a substantial burst of this reactive oxygen species in both cell types. Real-time and longer-term measurements also showed a large burst of H2O2 production from tobacco cells, but not apple cells, when exposed to low temperatures. Lower temperatures reduced levels of peroxidase activity (both total and intracellular), with the heat pre-treatment preventing some of the cold-induced reduction of this activity in both apple and tobacco cells. The greater sensitivity to low temperature of the tobacco cells may be related to higher H2O2 production, with the heat treatment maintaining higher peroxidase activity. The lesser sensitivity of the apple cells may be due to the lack of a H2O2 burst and maintenance of peroxidase activity by the heat treatment. These results support a role for oxidative metabolism in the beneficial effects of heat in inducing low temperature tolerance.
A comparison of UV-B induced stress responses in three barley cultivars
Authors: Hideg Éva , Rosenqvist Eva , Váradi Gyula , Bornman Janet , Vincze Éva
Published: January 2006

In order to investigate the role of potential genotypic differences in three economically important barley cultivars, experiments were carried out to determine the influence of supplemental ultraviolet-B (UV-B, 280–320 nm) radiation on reactive oxygen species (ROS), antioxidant activity and photosynthesis. Greenhouse-grown barley (Hordeum vulgare L.) cultivars ‘Cork’, ‘Prestige’ and ‘Golden Promise’ showed different responses to supplemental 280–320 nm (UV-B) representing 100, 138 and 238% levels of ambient biologically active UV-B radiation, respectively. Among the three cultivars studied, cv. Golden Promise was the most tolerant to UV-B, cv. Prestige was slightly more sensitive than cv. Cork. A comparison with the other two cultivars showed that under supplemental UV-B, Golden Promise leaves (i) retained a higher quantum yield of photosynthesis under photosynthetically active radiation (PAR, 400–700 nm) corresponding to growth conditions; (ii) had the smallest decrease in both electron transport rate and non-photochemical quenching under high PAR; (iii) contained less oxidized ascorbate [measured as dehydroascorbate or electron paramagnetic resonance (EPR) detectable monodehydroascorbate radicals] than either Cork or Prestige. Under the highest UV-B level applied, Golden Promise leaves maintained the same activity of both monodehydroascorbate-reductase (MDAR) and ascorbate-peroxidase (APX) enzymes, as untreated controls, while MDAR markedly decreased in the other two cultivars and APX slightly increased in cv. Prestige. These features, together with the observation of directly EPR-trappable free radicals and the light-independent accumulation of monodehydroascorbate radicals in Cork and Prestige but not in Golden Promise leaves under high UV-B suggest that Golden Promise plants suffered less oxidative stress than the two other cultivars.
The polyphasic chlorophyll a fluorescence rise measured under high intensity of exciting light
Authors: Lazár Dušan
Published: January 2006

Chlorophyll a fluorescence rise caused by illumination of photosynthetic samples by high intensity of exciting light, the O–J–I–P (O–I1–I2–P) transient, is reviewed here. First, basic information about chlorophyll a fluorescence is given, followed by a description of instrumental set-ups, nomenclature of the transient, and samples used for the measurements. The review mainly focuses on the explanation of particular steps of the transient based on experimental and theoretical results, published since a last review on chlorophyll a fluorescence induction [Lazár D (1999) Biochimica et Biophysica Acta 1412, 1–28]. In addition to ‘old’ concepts (e.g. changes in redox states of electron acceptors of photosystem II (PSII), effect of the donor side of PSII, fluorescence quenching by oxidised plastoquinone pool), ‘new’ approaches (e.g. electric voltage across thylakoid membranes, electron transport through the inactive branch in PSII, recombinations between PSII electron acceptors and donors, electron transport reactions after PSII, light gradient within the sample) are reviewed. The K-step, usually detected after a high-temperature stress, and other steps appearing in the transient (the H and G steps) are also discussed. Finally, some applications of the transient are also mentioned.
Localised and non-localised promotion of fruit development by seeds in Arabidopsis
Authors: Cox Catherine M. , Swain Stephen M.
Published: January 2006

In Arabidopsis, as in the majority of flowering plants, developing seeds promote fruit growth. One method to investigate this interaction is to use plants with reduced seed set and determine the effect on fruit growth. Plants homozygous for a transgene designed to ectopically express a gene encoding a gibberellin-deactivating enzyme exhibit reduced pollen tube elongation, suggesting that the plant hormone gibberellin is required for this process. Reduced pollen tube growth causes reduced seed set and decreased silique (fruit) size, and this genotype is used to explore the relationship between seed set and fruit elongation. A detailed analysis of seed set in the transgenic line reveals that reduced pollen tube growth decreases the probability of each ovule being fertilised. This effect becomes progressively more severe as the distance between the stigma and the ovule increases, revealing the complex biology underlying seed fertilisation. In terms of seed-promoted fruit growth, major localised and minor non-localised components that contribute to final silique length can be identified. This result demonstrates that despite the relatively small size of the fruit and associated structures, Arabidopsis can be used as a model to investigate fundamental questions in fruit physiology.
Isolation of a NaCl-tolerant mutant of Chrysanthemum morifolium by gamma radiation: in vitro mutagenesis and selection by salt stress
Authors: Hossain Zahed , Mandal Abul Kalam Azad , Datta Subodh Kumar , Biswas Amal K.
Published: January 2006

A stable NaCl-tolerant mutant (R1) of Chrysanthemum morifolium Ramat has been developed by in vitro mutagenesis with gamma radiation (5 gray; Gy). Salt tolerance was evaluated by the capacity of the plant to maintain both flower quality and yield under NaCl stress. Enhanced salt tolerance of the R1 mutant was attributed to increased activities of reactive oxygen species (ROS)-scavenging enzymes, namely superoxide dismutase (SOD), monodehydroascorbate reductase (MDAR), dehydroascorbate reductase (DHAR) and glutathione reductase (GR), and to reduced membrane damage, higher relative water content (RWC), chlorophyll and carotenoids contents. RAPD analysis revealed two polymorphic bands (956 and 1093 bp) for the R1 mutant that might be considered as specific RAPD markers associated with salt tolerance. Better performance of the R1 progeny under identical salinity stress conditions, even in the second year, confirmed the genetic stability of the induced salt tolerance character. The R1 mutant developed by gamma ray treatment can be considered a salt-tolerant mutant showing all the positive characteristics of tolerance to NaCl stress.
TaNAC69 from the NAC superfamily of transcription factors is up-regulated by abiotic stresses in wheat and recognises two consensus DNA-binding sequences
Authors: Xue Gang-Ping , Bower Neil I. , McIntyre C. Lynne , Riding George A. , Kazan Kemal , Shorter Ray
Published: January 2006

NAC proteins are one of the largest families of plant transcription factors and have recently been implicated in diverse physiological processes. To elucidate their role in gene regulation, we determined the DNA-binding specificity of a drought- and cold-inducible NAC protein, TaNAC69 from wheat, and analysed its homologues from other species. Two consensus DNA-binding sequences (spanning 23–24 bp) of TaNAC69 were identified through binding site selection and both consisted of two half sites. Comprehensive data on the DNA-binding specificity of TaNAC69 were generated through extensive base substitution mutagenesis. TaNAC69 and its homologue in Arabidopsis, NAP, sharing 75% sequence identity in the NAC domain, exhibited similar DNA-binding specificity. TaNAC69 was able to homodimerise through its NAC domain. The NAC domain consists of five conserved subdomains. Subdomain mutation showed that a loss or reduction in TaNAC69 dimerisation capacity was accompanied with abolition or decrease in its DNA-binding activity. These data suggest that all subdomains are necessary to maintain a functional NAC domain structure required for interaction with DNA and dimerisation.
New Australian Thanocleridae, with notes on the biogeography of the subtribe Isoclerina Kolibác (Coleoptera : Cleroidea)
Authors: Kolibác Jiýí
Published: January 2006

Four new species of the family Thanerocleridae are described from Australia
(Queensland, New South Wales): Isoclerus
(Isoclerus) rumcajs,
I. (I.) manka, I. (I.) cipisek and
I. (I.) gerstmeieri. These species are the first records
of the family’s autochthonous members from the Australian continent. The
subgenus Isoclerus (Lyctosoma)
Lewis is synonymised with Isoclerus
(Isoclerus) Lewis. Hypotheses concerning the
biogeography of subtribe Isoclerina Kolibáÿč in which the
newly described species belong, are proposed. The ancestral area of Isoclerina
may be in Africa or somewhere in the region of Europe, Greenland and the
eastern part of North America – in either case, in the Lower to Middle
Cretaceous era. Also, pan-biogeographic hypotheses are formulated for the
distribution patterns of species of the subgenus
Isoclerus.
Australian stingless bees of the genus Trigona (Hymenoptera: Apidae)
Authors: Dollin Anne E. , Dollin Leslie J. , Sakagami the late Shôichi F.
Published: January 2006

Six Australian stingless bee species in Trigona
(Heterotrigona) are redescribed. Workers, males and
queens are described of T. clypearis Friese
(formerlyT. wybenica Cockerell),
T. sapiens Cockerell (formerly
T. laeviceps Smith), T. carbonaria
Smith, T. hockingsi Cockerell and an enigmatic fifth
species from north-western Australia. The name
T. mellipes Friese is assigned to this latter species on
morphometric and geographical grounds, despite differences in described
coloration. A key to the species is given. Species distributions and nest
descriptions based on 188 nests are provided. Workers of a sixth Australian
species, T. aff. fuscobalteata
Cameron, previously unknown in Australia but recently found on Cape York
Peninsula, Queensland, are also described.
Biology and identification of Aeolothripidae (Thysanoptera) in Australia
Authors: Mound Laurence A. , Marullo Rita
Published: January 2006

The diversity of biologies amongst Australian thrips of the family
Aeolothripidae is discussed. In the basal clades of this family species are
phytophagous, also sometimes monophagous and univoltine
(Cranothrips Bagnall and
Cycadothrips Mound). In the most advanced clades,
species are obligate predators, often on other thrips species
(Franklinothrips Back and
Mymarothrips Bagnall), but in the intermediate clades
many species are both phytophagous and facultative predators
(Aeolothrips Haliday and
Desmothrips Hood). Keys are provided to identify the 36
species and 12 genera known from Australia. Of these, 32 species and 5 genera
are endemic, and the southern continent relationships of this fauna are
discussed. Seven species are newly described:
Franklinothrips basseti, with unusual dark forewings,
from Queensland; Cranothrips bellisi, the smallest
member of this family and with the ovipositor greatly reduced, from the
Northern Territory near Darwin; Cycadothrips emmaliami,
from Macrozamia reidlei male cones in Western Australia;
Desmothrips chirus, a grass-living species with
remarkable Chirothrips-like females, from Darwin;
D. darwini, a second bicoloured grass-living member of
this genus, from Darwin; D. marilynae, in which males
have a unique abdominal chaetotaxy, from Western Australia;
D. stepheni, with unusually long cephalic setae, from
near the Gulf of Carpentaria. Variation in the bicoloured, grass-living
species Gelothrips cinctus Hood is discussed, and a
Mymarothrips species from Darwin is re-identified as the
Indonesian species M. bicolor Strassen.
Revision of leaf-beetles of the genus Cadmus Erichson, subgenus Lachnabothra Saunders (Coleoptera: Chrysomelidae: Cryptocephalinae)
Authors: Reid C. A. M.
Published: January 2006

The genus Cadmus Erichson, subgenus
Lachnabothra Saunders, is redefined and revised. It
includes at least 24 species, of which 7 are redescribed and 13 described as
new: bicornutus, burru,
clibanarius, gullanae,
karina, lawrencei,
magnus, malleecola,
mokarei, murrungga,
storeyi, tasmaniae,
walgalu. Four additional species, represented by females
or damaged males, are noted but not described. The following new synonymy is
recognised (senior synonym first): braccatus (Klug)
= saundersi Baly; breweri
Baly = duboulai Baly.
Cryptocephalus incoctus Lea and
Chlamydicadmus adspersatus Chapuis are transferred to
Cadmus (Lachnabothra). The latter
species name is a nomen dubium. Lectotypes are
designated for Lachnabothra distincta Baly,
Cryptocephalus incoctus Lea,
Lachnabothra waterhousei Baly and
Lachnabothra wilsoni Baly. The new definition excludes
all Cadmus (Lachnabothra) species
previously described from New Guinea. The larvae are described and for 10
species briefly diagnosed, the pupae are described, life-history observations
are noted and the phylogeny and biogeography of the species are discussed. The
species of Cadmus (Lachnabothra)
are found throughout southern and eastern Australia, where they feed on
eucalypts.
A revision of the Australian mite genus Australiseiulus Muma (Acarina: Phytoseiidae)
Authors: Beard Jennifer J.
Published: January 2006

The genus Australiseiulus Muma contains the most
holotrichous members of the mite family Phytoseiidae, and is the only known
endemic phytoseiid genus in Australia. The revised and redefined genus
contains five species in 2 species-groups, differentiated by the position of
podonotal setae z6 and the number of teeth on the movable cheliceral digit.
The australicus-group contains
A. australicus (Womersley) and
A. angophorae (Schicha); the
goondi-group contains A. goondi,
sp. nov., A. dewi, sp. nov. and
A. poplar, sp. nov. Both species-groups are defined, all
species are diagnosed, a key to adult females and detailed descriptions of the
three new species and A. australicus are provided. In
addition, immatures of A. australicus and
A. goondi are described for the first time.
Systematics and host relationships of Australasian Diolcogaster (Hymenoptera : Braconidae : Microgastrinae)
Authors: Saeed A. , Dangerfield P. C. , Austin A. D.
Published: January 2006

The braconid wasp genus Diolcogaster Ashmead is revised
for the Australasian region, and is recorded from New Zealand and New
Caledonia for the first time. A key to species is presented, the relationships
within the Microgastrinae and among species-groups of the genus, the size of
the world fauna, the biology and host relationships, and the distribution of
Australasian species are discussed. The connexus-group
sensu Nixon is expanded and redefined to include two
monotypic, non-Australasian groups (D. ippis Nixon and
D. reales Nixon), while the
spretus-group sensu Nixon is
expanded to include the monotypic group for
D. coenonymphae (Watanabe) from Japan. Twenty-six
species are recognised from Australasia:D. adiastola,
sp. nov., D. alkingara, sp. nov.,
D. ashmeadi, sp. nov.,
D. dichromus, sp. nov.,
D. eclectes (Nixon), D. euterpus
(Nixon), D. hadrommatus, sp. nov.,
D. harrisi, sp. nov., D. iqbali,
sp. nov., D. lucindae, sp. nov.,
D. masoni, sp. nov., D. merata,
sp. nov., D. muzaffari, sp. nov.,
D. naumanni, sp. nov.,
D. newguineaensis, sp. nov.,
D. nixoni, sp. nov.,
D. notopecktos, sp. nov.,
D. perniciosus(Wilkinson),
D. rixosus (Wilkinson),
D. robertsi, sp. nov., D. sons
(Wilkinson), D. tearae (Wilkinson),
D. tropicalus, sp. nov.,
D. vulpinus (Wilkinson),
D. walkerae, sp. nov. and
D. yousufi, sp. nov.
The marine Haloveliinae (Hemiptera:Veliidae) of Australia, New Caledonia and southern New Guinea
Authors: Andersen Nils Møller , Weir Tom A.
Published: January 2006

Water striders (Hemiptera, Gerromorpha) are common inhabitants of aquatic
habitats throughout the world. More than 150 species representing five
families have colonised the marine environment, chiefly coastal areas of
tropical seas in habitats with a strong tidal influence. The Australian fauna
of marine water striders is particularly diverse and species-rich, comprising
about 30 species. The present paper deals with the marine Haloveliinae
(Veliidae) of Australia, New Caledonia and southern New Guinea. They are
classified in two genera, Xenobates Esaki and
Halovelia Bergroth.
Xenobates mangrove, ovatus,
major and spinoides (Queensland),
X. lansburyi and chinai (Northern
Territory), and X. caudatus (southern Papua New Guinea)
are described as new. X. myorensis (Lansbury),
X. angulanus (Polhemus) and
X. loyaltiensis (China) comb. nov. are redescribed.
Descriptive notes are presented for the five species of
Halovelia recorded from Australia. Keys to adults of all
species are provided and their distributions mapped. Finally, we discuss the
zoogeography and ecology of the marine Haloveliinae of Australia.
Establishment of a subfamily Aphyssurinae for the Australian genus Aphyssura Hardy (Diptera : Calliphoridae), with a review of known forms and descriptions of new species
Authors: Norris K. R.
Published: January 2006

The subfamily Aphyssurinae, herein established, comprises only the
precinctively Australian genus Aphyssura Hardy. These
flies are all small (overall length up to ca. 5 mm) and of fairly uniform
structure. The subfamily and genus are characterised as follows: the long
arista is sparsely plumose on the basal quarter of its third segment, and
thence spiculate to the apex; the prosternum is sparsely bristled; some
bristles (anterior presutural intraalar, immediately presutural intraalar,
lateral scutellars and intrapostalar) are lacking; cell r 4+5 is closed
or even has a short appendix; the calypteres are bare; the males have a
relatively narrow frons, an uncleft fifth sternite armed with a down-turned
subapical spine; the cerci are completely fused. The females often completely
different from the males in coloration, and the dorsal sclerites of the
ovipositor are greatly reduced; reproduction is by larviparity. The previously
described species – A. minuta (Malloch),
A. dubia (Walker) and A. pusilla
(Macquart) – are characterised. The following new species are described:
A. arenicola, A. attonita,
A. banksi, A. contexta,
A. crassigaster, A. cygnea,
A. eyrei, A. halli,
A. humei, A. ioannes,
A. liepae, A. mongensis,
A. narrogina, A. nigricans,
A. rubida, A. rustica,
A. southcotti, A. sturti,
A. tanni, A. territorialis,
A. therribriana, A. tonnoiri,
A. ungarrana, and A. zentae. A key
to species is given. Illustrations of diagnostic features of the male and
female terminalia are given.
Systematics of Nitidulinae (Coleoptera:Nitidulidae): phylogenetic relationships, convexity and the origin of phallalophagy
Authors: B.Leschen Richard A.
Published: January 2006

Nitiduline beetle genera of the Cyllodes complex arestudied in the context of a phylogenetic analysis of 19 ingroup and eightoutgroup taxa and 63 characters derived from adult morphology and hostrelationship. In this analysis, the Cyllodes complex isshown to be monophyletic. By eliminating the problematic taxonCamptodes and a priori weightingof the presence/absence of procoxal rests, two monophyletic taxa areobtained within the Cyllodes complex(Cyllodes and Oxycnemus groups). Aphylogenetic analysis of 13 terminal taxa represented by larval and adultsemaphoronts shows a monophyletic Cyllodes complex inone of two trees. The Cyllodes complex is formallyrecognised as Cyllodini Everts, containing two or more monophyletic groupsthat are recognised on an informal basis. The Oxycnemusgroup is well supported and may include the enigmatic genusCamptodes. Taxonomic actions include two synonymiesunder Apsectochilus Reitter (=Meoncerus Sharp, syn. nov.; =Lordyrops Reitter, syn. nov.) and type speciesdesignations for Neotropical genera described by David Sharp(Apsectochilus, Eusphaerius,Mecyllodes, and Somatoxus).Carinocyllodes, gen. nov. (type species:Eusphaerius lubricus Leschen & Carlton) is describedand includes two additional species (C. belli, sp. nov.and C. depressus, sp.nov.).Convexity is a character complex in nitidulids, and must be partitioned forphylogenetic reconstruction and character analysis. Two classes of charactervariation (dependent and independent) are discussed with regard to theevolution of convexity in the context of cladograms. A highly convex form withthe capability to roll into a ball by tucking the head beneath the prothoraxhas evolved at least one or more times in Nitidulidae and several times inunrelated beetle families.Fungal host-use patterns are highly concordant with the phylogenetic branchingpattern in Cyllodini. Most members are associated with large-bodiedBasidiomycetes, with the exception of Camptodes whichoccurs on flowers and develops in rotten vegetation. Most species of theOxycnemus group are restricted to Phallales, an obligatehost pattern that is old relative to those associations in the remainingCyllodini that occur on other fungi. Another significant shift occurred fromphallalophagy to phytophagy if the hypothesis is accepted thatCamptodes is a member of theOxycnemus group.
On the milliped family Heterochordeumatidae, with comments on the higher classification of the order Chordeumatida (Diplopoda)
Authors: Shear William A.
Published: January 2006

A new genus and species,
Infulathrix siam, gen. et sp. nov. and a new species,
Heterochordeuma petarberoni, sp. nov. are described from
southeast Asia, and the previously known members of the Heterochordeumatidae
are reviewed. The genusSumatreuma Hoffman is placed in
the synonymy of Heterochordeuma Pocock.
Heterochordeumatid gonopod structure is not primitive, as previously supposed,
but apomorphic within the superfamily Heterochordeumatoidea and the Diplopoda
in general. The families of the order Chordeumatida are grouped into four
suborders: Chordeumatidea, Heterochordeumatidea, Craspedosomatidea and
Striariidea.
Revision of the genus Clinocera Meigen from Australia and New Zealand (Diptera : Empididae : Clinocerinae)
Authors: Sinclair Bradley J.
Published: January 2006

The Australian and New Zealand species of
Clinocera Meigen are revised.
Clinocera gressitti Smith is known from Campbell Island
(New Zealand) and the following seven new species are recognised from eastern
Australia: C. australiana, sp. nov.,
C. bickeli, sp. nov., C. irrorata,
sp. nov., C. monticola, sp. nov.,
C. queenslandica, sp. nov.,
C. rubriventris, sp. nov. and
C. spinosa, sp. nov. All species are described and
illustrated. A key to species of Clinocera from
Australia and New Zealand is provided and phylogenetic relationships and
biogeographic patterns are discussed.
Accumulation of starch in wheat grain under different shoot/root temperatures during maturation
Authors: Guedira Mohammed , Paulsen Gary M.
Published: January 2006

The impact of high temperatures on accumulation of starch in the grain of
wheat (Triticum aestivum L.) is usually attributed to
direct effects of the stress on the enzymes involved. However, roots are
extremely sensitive to temperatures that can be as high as those experienced
by the shoots, and their role in whole-plant responses should be considered.
Wheat (cv. Len) was grown at 15/15, 30/15, 15/30, and
30/30˚C shoot/root temperatures during maturation, and
accumulation of dry matter and N, contents of sucrose and starch, and
activities of enzymes in the pathway of starch assimilation in the endosperm,
were measured weekly. Dry matter and N accumulation were affected more by root
than by shoot temperatures. High whole-plant temperatures (30/30˚C)
accelerated linear grain growth but diminished the duration of assimilation,
the contents of sucrose and starch, and the activities of the enzymes
involved. The effects of high root temperature (15/30˚C) resembled
those of high whole-plant temperature, whereas low root temperature
(30/15˚C) tended to ameliorate them. Sucrose synthase and soluble
starch synthase were affected more than the other enzymes by high shoot
and/or root temperature. However, treatments that caused the lowest
activities resulted in the fastest, but briefest, linear rates of grain
growth. We concluded that shoots and roots interact in the response of wheat
to high temperature, and that stress on both organs affects accumulation of
starch in grain.
Putative effects of pH in intra-chloroplast compartments on photoprotection of functional photosystem II complexes by photoinactivated neighbours and on recovery from photoinactivation in Capsicum annuum leaves
Authors: Lee Hae-Youn , Hong Young-Nam , Chow Wah Soon
Published: January 2006

Leaf segments from Capsicum annuum L. plants grown at
100 (low light) or 500 (high light) μmol photons
m–2 s-1 were illuminated in
the presence of nigericin, dithiothreitol (DTT), or high
[CO2] (1% in air), with or without
lincomycin, an inhibitor of chloroplast-encoded protein synthesis. At various
times, the remaining fraction (f ) of functional PSII
complexes was measured by a dark-adapted chlorophyll fluorescence parameter
(1/Fo–
1/Fm; where
Fo and Fm are the fluorescence
yields corresponding to open and closed PSII traps, respectively), which was
calibrated by the oxygen yield per saturating single-turnover flash. The
results were interpreted according to a simple kinetic model incorporating the
hypothesis that photoinactivated PSII complexes photoprotect functional
neighbours (Lee et al. 2001,
Planta 105, 377–384),
yielding the rate coefficients of photoinactivation and repair, and a
parameter, a, which phenomenologically describes the
effectiveness of photoprotection by photoinactivated PSII complexes. The
presence of the uncoupler nigericin during illumination greatly decreased a by
an order of magnitude, suggesting that a sufficiently acidic thylakoid lumen
may be required for the photoprotective mechanism to operate. Both nigericin
and high [CO2] decreased the rate coefficient
of repair several fold, suggesting that the stromal pH was non-optimal for
protein synthesis in the presence of nigericin or high
[CO2]. The xanthophyll cycle, inhibited by
DTT, seemed to have a minimal effect on the rate coefficients of
photoinactivation and repair, and on the parameter a.
The results underline the importance of optimal pH in both the stroma and
lumen for photoprotection, and recovery from photoinactivation of PSII.
Effects of drought on photosynthesis in grapevines under field conditions: an evaluation of stomatal and mesophyll limitations
Authors: Flexas Jaume , Bota Josefina , Escalona José M. , Sampol Bartolomé , Medrano Hipólito
Published: January 2006

The effect of diffusional and photochemical limitations to photosynthesis was
assessed in field-grown water-stressed grapevines
(Vitis vinifera L.) by combined measurements of gas
exchange and chlorophyll fluorescence. Drought was slowly induced, and the
progressive decline of photosynthesis was examined in different grapevine
cultivars along a continuous gradient of maximum mid-morning values of
stomatal conductance (g), which were used as an
integrative indicator of the water-stress conditions endured by the leaves.
Initial decreases of g were accompanied by decreases of
substomatal CO2 concentration (Ci), the estimated
chloroplastic CO2 concentration (Cc) and net
photosynthesis (AN), while
electron transport rate (ETR) remained unaffected. With increasing drought,
g, AN, Ci
and Cc further decreased, accompanied by slight decreases of ETR and of the
estimated mesophyll conductance
(gmes). Severe drought led to
strong reductions of both g and
gmes, as well as of ETR. The
apparent carboxylation efficiency and the compensation point for
CO2 remained unchanged under severe drought when
analysed on a Cc, rather than a Ci, basis, suggesting that previously reported
metabolic impairment was probably due to decreased
gmes.
Research note: The 35S promoter is not constitutively expressed in the transgenic tropical actinorhizal tree Casuarina glauca
Authors: Smouni Aziz , Laplaze Laurent , Bogusz Didier , Guermache Fathia , Auguy Florence , Duhoux Emile , Franche Claudine
Published: January 2006

The tropical nitrogen-fixing tree, Casuarina glauca
Sieb. ex Spreng. was genetically transformed using
Agrobacterium tumefaciens C58C1(pGV2260; pBIN19GUSINT).
We report on the expression pattern conferred by the cauliflower mosaic virus
(CaMV) 35S promoter in transgenic C. glauca plants grown
in vitro, and for one year in a greenhouse.
Histochemical assays in shoots from in vitro plants
revealed β-glucuronidase (GUS) staining in apical and axillary buds, and
in nearly all tissues near the base of the stem. In roots, the CaMV 35S drove
strong GUS expression in the apex and vascular tissue. In 1-year old plants
grown in a greenhouse, the CaMV 35S promoter was highly active, except in
peripheral suberized tissues. Transgenic C. glauca
plants were nodulated by the actinomycete Frankia.
Histochemical assays on vibratome sections of transgenic nodules demonstrated
intense GUS activity in the vascular bundle, the phellogen, and in strands of
uninfected cells filled with polyphenols. GUS expression was undetectable in
Frankia-infected cells.
Apple leaf sucrose-phosphate synthase is inhibited by sorbitol-6-phosphate
Authors: Zhou Rui , Sicher Richard C. , Quebedeaux Bruno
Published: January 2006

Sucrose-phosphate synthase (SPS) from mature apple
(Malus domestica Borhk. cv. Gala) leaves was purified
34-fold to a final specific activity of 15.3 μmol
mg–1 protein h–1. The
enzyme showed hyperbolic saturation kinetics for both fructose-6-phosphate
(F6P) (Km= 0.36 mM) and
uridine-5′-diphosphoglucose (UDPG)
(Km = 6.49 mM).
Glucose-6-phosphate (G6P) was found to be an activator of apple SPS, and the
activation was dependent upon the F6P concentration. At a concentration of 2
mM, G6P significantly decreased the
Km for F6P and increased SPS
activity. However, higher concentrations of G6P did not further stimulate SPS
activity. In contrast to SPS from other plant species, inorganic phosphate
(Pi) had little or no inhibitory effect on apple SPS. The apple leaf enzyme
was inhibited 7–10% by 10 mM Pi when F6P concentrations were in
the range of 2–10 mM. We observed that sorbitol-6-phosphate, an
intermediate metabolite in sorbitol biosynthesis, was a competitive inhibitor
of SPS with a Ki of 1.83 mM.
Sorbitol-6-phosphate also inhibited G6P activation of SPS. Our results suggest
that sucrose biosynthesis may be altered by the products of sorbitol
biosynthesis in apple leaves.
Rhythmic patterns of nutrient acquisition by wheat roots
Authors: Shabala Sergey , Knowles Andrew
Published: January 2006

Oscillatory patterns in H+,
K+, Ca2+ and
Cl- uptake were observed at different regions of the
root surface, including root hairs, using a non-invasive ion flux measuring
technique (the MIFE™ technique). To our knowledge, this is the first
report of ultradian oscillations in nutrient acquisition in the mature root
zone. Oscillations of the largest magnitude were usually measured in the
elongation region, 2–4 mm from the root apex. There were usually at
least two oscillatory components present for each ion measured: fast, with
periods of several minutes; and slow, with periods of 50–80 min. Even
within the same functional zone, the periods of ion flux oscillations were
significantly different, suggesting that they are driven by some internal
mechanisms located in each cell rather than originating from one
‘central clock pacemaker’. There were also significant changes in
the oscillatory characteristics (both periods and amplitudes) of fluxes from a
single small cluster of cells over time. Analysis of phase shifts between
oscillations in different ions suggested that rhythmic activity of a plasma
membrane H+-pump may be central to observed rhythmic nutrient acquisition
by plant roots. We discuss the possible adaptive significance of such an
oscillatory strategy for root nutrient acquisition.
Response of abscisic acid mutants of Arabidopsis to salinity
Authors: Cramer Grant R.
Published: January 2006

Increases in abscisic acid (ABA) concentrations in plant tissues correlate
with growth inhibition in salt-stressed plants. Therefore, it was hypothesized
that Arabidopsis ABA mutants different in, or
insensitive to, ABA would respond differently than wild type (wt) to salinity
stress. Seeds (wt, abi1-1, abi2-1,
abi3-1, and aba1-3) were
germinated and grown hydroponically in three separate experiments with
different environmental conditions: relative humidity at 80 or 100%,
day/night temperatures at 21/18 or 23/20˚C, and light
intensity at 125, 200 or 350 μmol photons m–2
s-1. Plants were exposed to salinity (either 0, 40 and
80 mM NaCl or 1, 5, and 9 dS m–1 with a Na/Ca
ratio of 10 depending on the experiment) for one to several weeks before
harvesting. The effect of salinity on root elongation rates of young seedlings
was measured as well. Two-way ANOVA of root elongation rates of young
seedlings and the growth of 3-week old plants in hydroponic solutions
indicated that salinity inhibited growth, increased ABA and Na concentrations,
and reduced K concentrations in all genotypes tested. However, there were no
significant interactions with salinity and genotype for root elongation rates,
total dry weight, shoot ABA and K concentrations. Shoot Na concentrations were
significantly higher in wt plants relative to other genotypes subjected to
high salinity stress. aba1-3 had significantly lower ABA
concentrations than other genotypes, but the interaction of
aba1-3 with salinity was the same as other genotypes.
The lack of difference in interaction between genotype and salinity indicates
that all genotypes responded in the same manner and amount to salinity for the
particular parameter measured. Therefore, it appears that there are no
significant differences in growth in response to salinity between the ABA
mutants (ABA-deficient and ABA-insensitive) and wt. However, in contrast to
the other genotypes, some of the ABA-deficient plants,
aba1-3, died when exposed to high salinity
and high light intensity. ABA appears to provide a
protective role in conditions of high salinity and high light intensity.
An Arabidopsis thaliana mutant, altered in the γ-subunit of ATP synthase, has a different pattern of intensity-dependent changes in non-photochemical quenching and kinetics of the P-to-S fluorescence decay
Authors: Govindjee  , Spilotro Paul
Published: January 2006

A major photoprotective mechanism that plants employ against excess light
involves interplay between the xanthophyll cycle and the accumulation of
protons. Using mutants in the xanthophyll cycle, the roles of violaxanthin,
antheraxanthin and zeaxanthin have already been well established. In this
paper, we present data on intact leaves of a mutant [coupling factor
quick recovery mutant (cfq); atpC1:E244K] of
Arabidopsis thaliana that we expected, based on 515-nm
absorbance changes (Gabrys et al. 1994,
Plant Physiology 104,
769–776), to have differences in light-induced ΔpH. The
significance of this paper is: (i) it is the first study of the
photoprotective energy dissipation involving a mutant of the pH gradient; it
establishes that protons play an important role in the pattern of
non-photochemical quenching (NPQ) of chlorophyll (Chl) a
fluorescence; and (ii) differences between the cfq and the wild type (wt) are
observed only under subsaturating light intensities, and are strongest in the
initial few minutes of the induction period. Our results on light-intensity
dependent Chl* a fluorescence transients (the
Kautsky effect), and on NPQ of Chl a fluorescence, at
50–250 μmol photons m–2
s–1 demonstrate: (i) the
‘P-to-S’ (or
‘T’) decay, known to be related to
[H+] (Briantais
et al. 1979,
Biochimica et Biophysica Acta 548,
128–138), is slowed in the mutant; and (ii) the pattern of NPQ kinetics
is different in the initial 100 s — in the wt leaves, there is a marked
rise and decline, and in the cfq mutant, there is a slowed rise. These
differences are absent at 750 μmol photons m–2
s–1. Pre-illumination and nigericin (an uncoupler
that dissipates the proton gradient) treatment of the cfq mutant, which has
lower ΔpH relative to wild type, confirm the conclusion that protons
play an important role in the quenching of Chl a
fluorescence.
The influence of nutrients on growth and photosynthesis of seedlings of two rainforest dipterocarp species
Authors: Bungard Ralph A. , Zipperlen Shirley A. , Press Malcolm C. , Scholes Julie D.
Published: January 2006

This study aims to determine the influence of nutrient additions in the form
of nitrogen (N), phosphorus (P) and potassium (K) on the photosynthetic
physiology, morphology and growth of
Dryobalanops lanceolata Burck and
Shorea johorensis Foxw., two co-existing dipterocarp
species in the understorey of secondary forest. Analysis of the light
environment revealed that the total daily irradiance in the understorey was
4.57 ± 0.70 mol photons m–2
d–1, approximately 20% higher than that
which could be expected to occur in the primary forest understorey. Around
50% of total irradiance occurred at fluxes over 400 μmol photons
m–2 s–1, and this was
received over 7% of the daylight period. Both
D. lanceolata and S. johorensis
grew over the 16-month study, but only S. johorensis
increased growth in response to nutrient additions. Neither species altered
biomass partitioning in response to additional nutrients. Both species also
showed increased rates of photosynthetic induction
(T0.5Asat)
in response to nutrient additions, but only
S. johorensis showed an increase in light-saturated
rates of photosynthetic capacity
(Asat), and the chlorophyll
content of leaves. We argue that additional nutrients increased the capacity
of S. johorensis to utilise the sporadic burst of high
irradiance in sunflecks. Analysis of the nutrient composition of leaves from
age cohorts up to > 16 months showed that additional nutrients increased
the P and K concentration in D. lanceolata leaves, and
the P and N content of S. johorensis leaves. This
suggests that neither P nor K were limiting the growth of
D. lanceolata in this secondary forest environment, but
that P and/or N may limit growth of S. johorensis.
Our data highlights differences in the ecology of two co-existing dipterocarp
species. We argue that D. lanceolata shows
characteristics consistent with a low resource-demanding species that may have
a competitive advantage over S. johorensis in low
resource environments, while S. johorensis shows traits
better suited to higher resource availability. Thus, there are distinct
species-specific differences in the ability to respond to nutrients that
depend on the irradiance environment, and which may have a role in niche
partitioning among the dipterocarps.
Floating row covers affect the molybdenum and nitrogen status of Chinese cabbage grown under field conditions
Authors: Moreno Diego A. , Víllora Gemma , Soriano Maria T. , Castilla Nicolas , Romero Luis
Published: January 2006

In three consecutive years of field experiments, an uncovered control
(T0), and floating row covers treatment
(T1: perforated polyethylene, 50 μm;
T2: polypropylene, 17 g m–2)
were used to produce different growth conditions for Chinese cabbage
[Brassica pekinensis (Lour) Rupr. cv. Nagaoka
50]. Five samplings (whole tops) were made between transplant and
harvest, and measurements were made of
NO3-,
NH4+. organic N, and Mo
concentrations, as well as nitrate reductase (NR) activity, and amino acids in
the whole shoots. The microclimatic conditions in T0
resulted in plants with higher Mo accumulation, as well as the highest basal
NR activity and the lowest NO3-
concentrations. The thermal environment under the T1
treatment induced the highest mean temperature values and resulted in plants
with the highest amino acid level, whereas the plants in the
T2 treatment with its intermediate thermal conditions,
had the lowest levels of Mo and the highest
NO3- concentrations. The floating
row covers influenced the Mo status, which in turn affected NR activity. In
addition, T1-polyethylene sheet and
T2fleece favoured an increase in the levels of
NO3- by the limitation in the NR
activity, with the consequent risk of a high NO
3- level in vegetables for human
consumption.