bluuebunny/crossref_metadata_2025 huggingface dataset:
Co‐existing grass species have distinctive arbuscular mycorrhizal communities
Authors: Vandenkoornhuyse P. , Ridgway K. P. , Watson I. J. , Fitter A. H. , Young J. P. W.
Published: October 2003

Arbuscular mycorrhizal (AM) fungi are biotrophic symbionts colonizing the majority of land plants, and are of major importance in plant nutrient supply. Their diversity is suggested to be an important determinant of plant community structure, but the influence of host‐plant and environmental factors on AM fungal community in plant roots is poorly documented. Using the terminal restriction fragment length polymorphism (T‐RFLP) strategy, the diversity of AM fungi was assessed in 89 roots of three grass species (Agrostis capillaris,Festuca rubra,Poa pratensis) that co‐occurred in the same plots of a field experiment. The impact of different soil amendments (nitrogen, lime, nitrogen and lime) and insecticide application on AM fungal community was also studied. The level of diversity found in AM fungal communities using the T‐RFLP strategy was consistent with previous studies based on clone libraries. Our results clearly confirm that an AM fungal host‐plant preference exists, even between different grass species. AM communities colonizing A. capillaris were statistically different from the others (P < 0.05). Although grass species evenness changed in amended soils, AM fungal community composition in roots of a given grass species remained stable. Conversely, in plots where insecticide was applied, we found higher AM fungal diversity and, inF. rubraroots, a statistically different AM fungal community.
Social pairing and female mating fidelity predicted by restriction fragment length polymorphism similarity at the major histocompatibility complex in a songbird
Authors: Freeman‐Gallant Corey R. , Meguerdichian Michael , Wheelwright Nathaniel T. , Sollecito Suzanne V.
Published: October 2003

Female birds often copulate outside the pair‐bond to produce broods of mixed paternity, but despite much recent attention the adaptive significance of this behaviour remains elusive. Although several studies support the idea that extra‐pair copulations (EPCs) allow females to obtain ‘good genes’ for their offspring, many others have found no relationship between female mating fidelity and traits likely to reflect male quality. A corollary to the good genes hypothesis proposes that females do use EPCs to increase the quality of young, but it is the interaction between maternal and paternal genomes — and not male qualityper se — that is the target of female choice. We tested this ‘genetic compatibility’ hypothesis in a free‐living population of Savannah sparrows (Passerculus sandwichensis) by determining whether females mated nonrandomly with respect to the major histocompatibility complex (Mhc). During both the 1994 and 1995 breeding seasons, female yearlings (but not older birds) avoided pairing withMhc‐similar males (P < 0.005). TheMhcsimilarity between mates also predicted the occurrence of extra‐pair young in first broods (P < 0.007) and covaried with estimates of genome‐wide levels of similarity derived from multilocus DNA fingerprinting profiles (P = 0.007). The overall genetic similarity between adults tended to predict female mating fidelity, but with less precision than theirMhcsimilarity (P = 0.09). In contrast, females appeared insensitive to the size, weight or age of males, none of which explained variation in female mating fidelity. Taken together, these results are consistent with the hypothesis that females sought complementary genes for their offspring and suggest either that the benefits of heterozygosity (at theMhc) drive female mating patterns or that the avoidance of inbreeding is an ultimate cause of social and genetic mate choice in Savannah sparrows.
Assessing population structure and gene flow in Montana wolverines (Gulo gulo) using assignment‐based approaches
Authors: Cegelski C. C. , Waits L. P. , Anderson N. J.
Published: October 2003

In North America, wolverines once occupied a continuous range from Alaska southward to New Mexico. In the lower 48 states, small remnant populations remain only in the northwestern United States. Among these remnant populations, the Montana population has the highest probability of long‐term persistence given its size and proximity to healthy populations in Canada. In this study, we evaluate population genetic structure and gene flow among Montana wolverines using 10 polymorphic microsatellite loci. Bayesian and frequency‐based assignment tests revealed significant population substructure and provide support for at least three subpopulations in Montana. FST values between subpopulations ranged from 0.08 to 0.10 and provide evidence for male‐biased dispersal. The high degree of population substructure and low levels of gene flow contrast results from wolverine population genetic studies in less fragmented landscapes of Alaska and Canada. This study provides additional support for the hypothesis that large carnivore populations of Montana are becoming increasingly fragmented due to human development and disturbance.
Genetic effects of habitat fragmentation in Viola pubescens (Violaceae), a perennial herb with chasmogamous and cleistogamous flowers
Authors: Culley Theresa M. , Grubb Thomas C.
Published: October 2003

The reproductive biology of a plant species is important in the response of populations to habitat fragmentation, especially if plant–pollinator interactions are disrupted. The genetic effects of forest fragmentation were examined in the common understorey herb Viola pubescens, a species that produces self‐pollinated cleistogamous (CL) flowers and potentially outcrossing chasmogamous (CH) flowers. Using allozymes, we measured genetic variation in different sized populations. These were located in woodlots of various sizes (0.5–40.5 ha) and distances from one another (0.3–46 km) within the agricultural landscape of central Ohio in the Midwestern United States. Changes in forest cover of each woodlot within the past 180 years were determined from historical sources and aerial photographs. Woodlot and population sizes were significantly and positively correlated with measures of genetic variation (A, P, HO and HE), with variation highest in populations in the largest woodlot population and lowest in the smallest woodlot population. Most large woodlots resulted from fluctuations in forest cover over the past 60 years, while smaller fragments remained the same size. Overall, populations in Crawford County were genetically differentiated from one another (θ = 0.34), but there was no relationship between genetic and geographical distance. Preliminary evidence for a single year indicated a high rate of outcrossing in most populations. Despite the CH/CL reproductive advantage and apparent outcrossing, populations of V. pubescens in small woodlots remain susceptible to potentially detrimental effects of fragmentation such as genetic drift and reduced levels of genetic variation.
A molecular phylogeography approach to biological invasions of the New World by parthenogenetic Thiarid snails
Authors: Facon B. , Pointier J.‐P. , Glaubrecht M. , Poux C. , Jarne P. , David P.
Published: October 2003

The parthenogenetic snail Melanoides tuberculata, present in tropical fresh waters of most of the Old World before 1950, has now invaded the Neotropical area. The phylogeography of this snail was studied to evaluate the pathways and number of such invasions. Because of parthenogenetic reproduction, individuals are structured into genetical clones. Within populations from both the original and invaded areas, several morphologically distinct clones (referred to as morphs) often coexist but the amount of genetic divergence among morphs is unknown. Individuals from 27 morphs and 40 populations world‐wide were sequenced at two mitochondrial genes (12S and 16S). Our phylogenetic reconstruction suggests that (i) most of the morphological variation observed in the New World predates invasion, (ii) at least six independent introductions have occurred, and (iii) invasive clones are found throughout most of the phylogenetic tree and do not come from a particular region of the area of origin. Two ideas are discussed in the light of these results. The first lies with the specificities of parthenogenesis in an invasion context. While in sexual species, independently introduced populations eventually merge into a single invasive population, in a parthenogenetic species independently introduced clones have distinct invasion dynamics and possibly exclude each other. Second, although repeated invasions in Melanoides may have an impact on indigenous molluscan faunas, their most likely effect is the world‐wide homogenization of the invasive taxon itself.
Conservation genetics of the wood ant,Formica lugubris, in a fragmented landscape
Authors: Gyllenstrand N. , Seppä P.
Published: October 2003

Various intrinsic factors connected to the special features of sociality influence the persistence of social insect populations, including low effective population size, reduced amount of genetic variation easily leading to inbreeding depression, and spatially structured populations. In this work, we studied an isolated, small and fragmented population system of the red wood antFormica lugubris, and evaluated the impact of social and genetic population structure on the persistence and conservation of the populations. The effective population size was large in our study population because all nests were polygynous. As a result, and despite the apparent isolation, the amount of nuclear genetic variability was similar to that in a nonisolated population system. Lack of inbreeding, as well as a high level of variability, indirectly suggests that this population does not suffer from inbreeding depression. The spatial distribution of genetic variation between local populations suggests intensive, but strongly male‐biased, nuclear gene flow. Thus, the persistence of this population system does not seem to be threatened by any immediate social or genetic factor, but colonization of new habitat patches may be difficult because of restricted female dispersal.
Recent evolutionary history of the bluethroat (Luscinia svecica) across Eurasia
Authors: Zink Robert M. , Drovetski Sergei V. , Questiau Sophie , Fadeev Igor V. , Nesterov Evgeniy V. , Westberg Michael C. , Rohwer Sievert
Published: October 2003

We analysed mitochondrial DNA (mtDNA) sequences from 154 bluethroats (Luscinia svecica) sampled at 21 sites throughout much of their Eurasian range. A previously reported, single base‐pair mtDNA difference between L. s. svecica and L. s. namnetum was inconsistent upon expanded geographical sampling. A significant FST value (0.29) and an isolation‐by‐distance effect show the existence of geographical differentiation. Phylogenetic analysis of haplotypes revealed northern and southern groups, although lineage sorting is incomplete. There was no geographical structure to the haplotype tree within groups, and currently recognized subspecies were not supported. A minimum evolution tree based on pairwise mtDNA genetic distances among average samples showed the same two broadly distributed northern and southern groups. These groups abut in the centre of the latitudinal range, and were possibly isolated by forest that developed and spread westward over the last 15 000 years. Pairwise FST values averaged 0.16 in the southern group, 0.04 in the northern group, and 0.42 between groups. Mismatch distributions suggested population growth in each group, with that in the south being more recent. In the northern group, the geographical pattern in tau suggested northward and eastward expansion. Analysis of nucleotide diversity suggested westward expansion in the southern group. The northern group had higher nucleotide diversity than the southern group, consistent with a larger current population size in the north. Given the significant FST, incompletely sorted haplotype tree, and broadly patterned minimum evolution tree, L. svevica appears to represent a species at an intermediate stage of differentiation between panmixia and reciprocal monophyly.
A cyclophilin gene marker confirming geographical differentiation of Norway spruce populations and indicating viability response on excess soil‐born salinity
Authors: Bozhko M. , Riegel R. , Schubert R. , Müller‐Starck G.
Published: October 2003

A newly identified cyclophilin‐encoding cDNA clone was used to design a codominant inherited EST‐PCR marker in Norway spruce. The study of the current minor polymorphism revealed a geographically structured differentiation pattern across 17 test populations, showing a slight clinal variation south‐north through Europe. Based on the frequency of alleles, isolation‐by‐distance analysis and the Ewens‐Watterson test, we conclude that a selectively neutral random‐drift mutation recently occurred within the Alpine population group, thus being responsible for the genetic variation detected. Analysis of tolerant and susceptible subsets of two adjacent Bavarian spruce populations affected by soil‐born NaCl pollution, revealed that the cyclophilin marker locus also confirms biased genotype frequencies. Considering an unlinked PCR marker of a ribosomal protein‐encoding EST clone, deviations between pooled tolerant subsets and pooled sensitive subsets were proven to be more significant for two‐locus homozygous genotypes than for each locus alone. We suggest that both loci are linked to adaptive genomic regions. Their potential to test the feasibility of marker‐assisted selection of both NaCl‐tolerant and drought resistant tree populations is discussed.
Estimating effective paternity number in social insects and the effective number of alleles in a population
Authors: Nielsen Rasmus , Tarpy David R. , Reeve H. Kern
Published: October 2003

Estimating paternity and genetic relatedness is central to many empirical and theoretical studies of social insects. The two important measures of a queen's mating number are her actual number of mates and her effective number of mates. Estimating the effective number of mates is mathematically identical to the problem of estimating the effective number of alleles in population genetics, a common measure of genetic variability introduced byKimura & Crow (1964). We derive a new bias‐corrected estimator of effective number of types (mates or alleles) and compare this new method to previous methods for estimating true and effective numbers of types using Monte Carlo simulations. Our simulation results suggest that the examined estimators of the true number of types have very similar statistical properties, whereas the estimators of effective number of types have quite different statistical properties. Moreover, our new proposed estimator of effective number of types is approximately unbiased, and has considerably lower variance than the original estimator. Our new method will help researchers more accurately estimate intracolony genetic relatedness of social insects, which is an important measure in understanding their ecology and social behaviour. It should also be of use in population genetic studies in which the effective number of alleles is of interest.
Urine‐based enzyme‐linked immunosorbent assay for the detection of Helicobacter pylori antibodies in children
Authors: Shimizu T , Yarita Y , Haruna H , Kaneko K , Yamashiro Y , Gupta R , Anazawa A , Suzuki K
Published: October 2003

Objective:  Recent studies of urine‐based enzyme‐linked immunosorbent assays (ELISA) for detection of antibody to Helicobacter pylori (H. pylori) have already shown high sensitivity and specificity in adults. The diagnostic accuracy of these assays in children was investigated.

Methods:  The results of serum and urine‐based ELISAs were compared with those of 13C‐urea breath tests (13C‐UBT) and/or detection of faecal H. pylori antigen in 68 children. The effect of urine total immunoglobulin G (IgG) levels on the ELISA results for anti‐H. pylori antibodies in urine was also examined.

Results:  The sensitivity, specificity and accuracy of the serum ELISA were 72.7%, 96.3%, and 92.3% respectively, while those of the urine‐based ELISA were 92.3%, 76.4%, and 79.4% respectively. The level of urine total IgG in children with false‐positive results in the urine‐based ELISA, was significantly higher than that in children who showed negative results in both the urine‐based ELISA and the 13C‐UBT and/or faecal H. pylori antigen tests. Human γ‐globulin affected the urine‐based ELISA results at final concentrations of 2.0 mg/dL, 3.0 mg/dL, and 4.0 mg/dL; the anti‐H. pylori antibody values were significantly higher than the ELISA values without the addition of human γ‐globulin.

Conclusion:  The findings suggested that the specificity of urine‐based ELISA for detection of H. pylori antibodies is low in children, since high urinary levels of total IgG increase the likelihood of false‐positive results.
How well do diagnosis‐related groups perform in the case of extremely low birthweight neonates?
Authors: Beeby PJ
Published: October 2003

Objective:  To determine how well diagnosis related groups (DRG) perform for extremely low birthweight neonates, by examining length of stay (LOS) data for babies with birthweight of 750−999 g and managed in the seven New South Wales maternity hospital neonatal intensive care units (NICU).

Methodology:  Neonates with an admission weight of 750−999 g and admitted to one of the seven NICU were studied. Those who died or were transferred in the first 5 days were excluded, leaving the group of neonates defined by DRG P62Z. In order to allow comparisons between the different NICU, neonates whose care was split between two or more NICU were also excluded, leaving those who either died, were transferred to a nursery closer to their home or were discharged directly to their home. The relationship between LOS and a number of perinatal factors was studied for the total group, and LOS data were compared for individual hospitals.

Results:  Length of stay was most strongly associated with mode of separation. It was also significantly associated with gestational age, time ventilated, oxygen need at 36 weeks postconceptual age, and retinopathy of prematurity. Neonatal intensive care units with the highest proportion of neonates being transferred had the lowest average LOS, and vice versa.

Conclusions:  The LOS of neonates in DRG P62Z is more strongly related to mode of separation (died, transferred or discharged home) than to factors that reflect best practice. A funding model that rewards NICU for a short LOS may unfairly disadvantage some units while favouring others.
Pilot study of a pain assessment tool in the Neonatal Intensive Care Unit
Authors: Marceau J
Published: October 2003

Objectives:  To develop and validate a pain assessment tool to assess procedural pain experienced by mechanically ventilated neonates.

Methods:  Assessment of ventilated infants, before, during and after a known routine traumatic procedure using the Nepean Neonatal Intensive Care Unit Pain Assessment Tool (NNICUPAT). This tool scores physiological and behavioural responses to pain. Variables used in the NNICUPAT included facial expression, body movement, skin colour, saturation, respiratory rate, heart rate and nurses’ perception of pain. To test the validity of the NNICUPAT, it was compared to a visual analogue scale (VAS), which is a unidimesional observation measure, where zero equals no pain and 10 equals severe pain.

Results:  Thirty ventilated neonates (mean gestation 28 ± 3.3 standard deviation (SD)) weeks) were enrolled in the pilot study over a 9‐month period. The total score before the procedure was: 0.26 ± 0.14 (mean ± standard error of the mean (SEM)) range 0−3; total score during the procedure 5.1 ± 2.2 (mean ± SD) range 1−10; and the total score after the procedure was 0.26 ± 0.15 (mean ± SEM) range 0−3. There was a significant correlation between the NNICUPAT and the VAS during the procedure (r = 0.825, P = < 0.01) and after the procedure (r = 0.375, P = < 0.05). Inter‐rater reliability was calculated between the principle coder and other coders (using the NNICUPAT) and showed a significant correlation before (r = 0.88, P < 0.01) and during (r = 0.88, P < 0.01) the procedure.

Conclusions:  The NNICUPAT does show validity in the assessment of procedural pain in the ventilated neonate. Further  evaluation of both inter‐ and intra‐rater reliability will be necessary to establish the ongoing validity of the NNICUPAT.
Use of complementary and alternative medicine in children: Too important to ignore
Authors: South M , Lim A
Published: October 2003

Abstract:  There is evidence that complementary and alternative medicine (CAM) is commonly being used for Australian children, however, at the same time, many doctors have little interest or understanding of the topic. Just as with mainstream treatments, CAM therapies have significant potential for adverse effects and drug interactions. Some of these are potentially serious. The use of CAM therapies in children is not an occasional fringe activity, and evidence suggests its usage will increase further. Whatever one's own views on the role of CAM in childrens health care, the topic is important and it should not be ignored.
Primary compliance with medication prescribed for paediatric patients discharged from a regional hospital
Authors: Wright H , Forbes D , Graham H
Published: October 2003

Objective:  To establish the rate of primary compliance with medication of children discharged from the paediatric ward of a regional hospital.

Methods:  All paediatric admissions to a regional hospital for a 14‐week period from April to July 2000 were studied. Patient data were collected for those paediatric inpatients discharged on medication. Written prescriptions kept by the local Aboriginal Medical Service and computerized data from local pharmacies were collected and the numbers filled were compared to ward discharge prescriptions.

Results:  There were 160 medical paediatric admissions. The median admission age was 19 months. There was no difference in patient sex, number of drugs prescribed, diagnosis of infection, mean age or the proportion of children under 2 years, between filled and unfilled prescriptions. In total, 49 prescriptions were filled from a total of 65 written (75%). This figure compares unfavourably with that of the metropolitan tertiary referral centre.

Conclusions : Primary compliance was suboptimal, with the majority of unfilled prescriptions being for antibiotics. These findings suggest that a remediable cause of treatment failure may be primary non‐compliance with medication in regional settings.
Oral sucrose for procedural pain in sick hospitalized infants: A randomized‐controlled trial
Authors: Harrison D , Johnston L , Loughnan P
Published: October 2003

Objective:  To determine the efficacy of 25% oral sucrose in the reduction of pain during a heel lance procedure in sick hospitalized infants.

Methodology:  In a blinded randomized‐ controlled trial, hospitalized infants were given either 1 mL 25% sucrose or 1 mL water 2 min prior to a heel lance procedure. Pain assessment comprised a four‐point facial expression score, incidence and duration of crying, heart rate and oxygen saturation changes.

Results:  A total of 128 infants were included. Facial scores immediately upon heel lance, and at 1 and 2 min in the recovery period were reduced in the treatment (sucrose) group compared to the placebo (water) group (P < 0.05). At other observation points, the differences in facial scores between the two groups of infants did not reach statistical significance. Neither incidence nor duration of crying whilst the blood collection was in progress was significantly reduced by sucrose. In  the 3‐min recovery period following completion of the blood collection, incidence and duration of crying were significantly less in the treatment group of infants (P < 0.05). Physiological responses of heart rate and oxygen saturation were not attenuated by sucrose at any time point during or following the blood collection.

Conclusion:  Oral sucrose was effective in reducing behavioural responses to pain upon heel lance and in the period following completion of a heel lance procedure in this group of sick hospitalized infants. This simple strategy can be promoted in institutions caring for sick babies, as a method of reducing behavioural responses to procedural pain.
Evaluation of standardized versus individualized total parenteral nutrition regime for neonates less than 33 weeks gestation
Authors: Yeung MY , Smyth JP , Maheshwari R , Shah S
Published: October 2003

Objective:  To evaluate the difference in nutrient intakes and biochemical responses in newborn infants <33 weeks gestation who received standardized versus individualized total parenteral nutrition (TPN) regimes.

Method:  Comparison of nutrient intakes and daily biochemical responses in newborn infants <33 weeks gestation who received standardized regime versus those who received individualized TPN regimes from day 2 to day 7 of life.

Results:  Twenty‐seven infants in the standardized TPN group and 31 infants in the individualized TPN group were compared. There were no statistically significant differences (P > 0.05) between the two groups in gestation, birthweight, Clinical Risk Index for Babies scores, daily TPN volume intake and biochemical responses. Infants in the standardized TPN group received less sodium (P < 0.01) and no potassium on day 2 as required, more protein (P < 0.02) every day, and more calcium and phosphate (P < 0.02 from day 4).

Conclusion:  There were no significant clinical and statistical differences in biochemical responses in newborn infants <33 weeks gestation who received standardized versus individualized TPN regimes during the first week of life. The economic cost of TPN provision using standardized TPN formulation was approximately 30% lower.
Estimation of the efficiency of the biconical trap for Glossina fuscipes fuscipes along the lake Victoria shore, Kenya
Authors: Odulaja Adedapo , Mohamed‐Ahmed Mohamed M.
Published: October 2003

Prior to estimating the efficiency of the unbaited biconical trap for Glossina fuscipes fuscipes Newstead (Diptera:Glossinidae) the flying height of the insects was estimated using 1 m2 electrified nets placed at 0 and 4 m above the ground level. The degree of avoidance of these nets by the flies was determined by comparing catches in traps surrounded and those not surrounded by incomplete rings of nets. On the basis of the catches in traps surrounded by nets, the expected catches on both sides of the nets were computed and compared with the observed catches, to further estimate this degree of avoidance. About 48% of males and 35% of females were captured above one metre. An average of 61% of males and 40% of females appeared to avoid the nets. Between 18% and 40% fewer tsetse were caught in traps surrounded by an incomplete ring of nets of respectively 1 m and 2 m radius than in traps not surrounded. After corrections for net avoidance and flying height, it appeared important to determine the optimum radius for the incomplete ring of nets for a reliable efficiency estimate.
Variation in defences of the plant Barbarea vulgaris and in counteradaptations by the flea beetle Phyllotreta nemorum
Authors: Nielsen Jens Kvist
Published: October 2003

Several sorts of variation in the interaction between the insect, Phyllotreta nemorum L. (Coleoptera:Chrysomelidae:Alticinae), and the plant, Barbarea vulgaris R.Br. (Brassicaceae), have been discovered: 1) genetic differences in the levels of defences in the plant, 2) genetic differences in the ability of insects to cope with the plant defences, 3) seasonal variation in levels of defences in the plant, and 4) differences between leaf types in levels of defences.

Two plant accessions were suitable for larval development throughout the season while the remaining nine accessions were more or less unsuitable for larvae from the ‘susceptible’ T‐population at least at certain times of the year. All accessions were suitable for the ‘resistant’ E‐population throughout the year. There was a seasonal variation in levels of defences in some accessions which were unsuitable for the T‐population during the summer period when beetles were present, but not during autumn and spring when the beetle were hibernating. Upper (younger) cauline leaves of these accessions had higher levels of defences than lower (older) cauline leaves. The resistant E‐population used B. vulgaris as a natural host plant while the susceptible T‐population did not. The use of B. vulgaris as a natural host plant by the E‐population of P. nemorum seems to be an extension of the host plant range of the species. Variation in plant defences may have facilitated the switch in host plant use by the resistant flea beetle population.
Mexican diabroticite beetles: II. Test for preference of cucurbit hosts by Acalymma and Diabrotica spp.
Authors: Eben Astrid , Barbercheck Mary E. , Martín Aluja S.
Published: October 2003

Field collected adult diabroticites were offered three Cucurbita spp. in various combinations. Three Acalymma and five Diabrotica (Chrysomelidae: Luperini) species were tested in feeding choice and no‐choice assays for their preference for bitter (cucurbitacin‐containing) over non‐bitter (without cucurbitacins) cucurbits, and for one of the two primary types of cucurbitacins. Tests were conducted in petri dishes and cages using plants in the cotyledon stage.

All species significantly preferred the bitter over the non‐bitter cucurbits (C. pepo L. var. Crookneck) in the tests offering a choice between cucurbitacin B‐containing plants (C. pepo L. var. Ambassador) and no cucurbitacin‐containing plants. Six species significantly preferred cucurbitacin E‐containing plants (C. martinezii L. Bailey) over no cucurbitacin‐containing plants. Cucurbitacin B‐containing plants were significantly preferred over cucurbitacin E‐containing plants. The previously observed preferences in choice tests no longer occurred in no‐choice tests. In cage experiments, beetles did not show preferences for a certain cucurbit host.

These observations are interpreted with regard to the kairomonal function of cucurbitacins for diabroticite beetles and the hypothesized evolutionary association between diabroticites and Cucurbitaceae.
Reproduction of Orius laevigatus and Orius albidipennis on pollen and Ephestia kuehniella eggs
Authors: Cocuzza G. E. , De Clercq P. , Van de Veire M. , De Cock A. , Degheele D. , Vacante V.
Published: October 2003

Reproduction and longevity of the anthocorid predators Orius laevigatus (Fieber) and Orius albidipennis (Reuter) (Heteroptera: Anthocoridae) were studied under controlled conditions in the laboratory. Three different diets were tested: eggs of the Mediterranean flour moth. Ephestia kuehniella Zeller, E. kuehniella eggs plus pollen, and pollen only. Small rooted plants of Spanish pepper (Capsicum annuum L. cv. ‘Creta’, long red) served as oviposition substrate and moisture source. In all treatments, total fecundity, oviposition period and female longevity of O. laevigatus were greater than that of O. albidipennis. When a diet of E. kuehniella eggs was supplemented with pollen, total fecundity of O. albidipennis was increased by about 40%. Female O. albidipennis fed only pollen laid five times less eggs than those fed flour moth eggs and pollen; also, longevity of females was shorter when only pollen was offered as food. Fecundity and longevity of O. laevigatus were not influenced when supplementing a diet of E. kuehniella eggs with pollen. Females of O. laevigatus receiving only pollen reduced egg production by about 60% but had a similar longevity as those receiving a diet including flour moth eggs. In either species, preoviposition period and egg hatch were not affected by diet. The ability of both anthocorids to use pollen as an alternative or additional food is discussed in relation to their practical use in integrated control programmes.
Effect of plants on the searching efficiency of a generalist predator: the importance of predator‐prey spatial association
Authors: Coll Moshe , Smith Lesley A. , Ridgway Richard L.
Published: October 2003

In most studies of tritrophic interactions, the effect of plants on predators is confounded with changes in prey and predator behaviors after an encounter event. Here, we estimate how the effect of plants on prey distribution (in the absence of the predator) and on predator foraging behavior (in the absence of prey) may influence predation rate of Orius insidiosus (Say) (Heteroptera: Anthocoridae) in 11 plant by prey species combinations. The within‐leaf distributions of O. insidiosus and its prey overlapped most on bean plants. The predator's foraging behavior (e.g., walking speed, turning rate) also differed among plant species. Simulations, using the prey distribution data and predator's foraging patterns on leaf surfaces of each plant species, show that, overall, the searching efficiency of O. insidiosus was higher on leaves of bean and corn than of tomato. However, the predator's searching efficiency was not consistent within plant species. Thus, the combined effect of plants directly on the predator and indirectly through the prey influenced the predator's searching efficiency.
Foraging success of parasitoid wasps on flowers: interplay of insect morphology, floral architecture and searching behavior
Authors: Patt Joseph M. , Hamilton George C. , Lashomb James H.
Published: October 2003

Intercropping with flowering herbaceous plants increases parasitoid survivorship, fecundity and retention and pest suppression in agroecosystems. Few studies, however, have examined the compatibility of parasitoid morphology and foraging ability with floral architecture. This study shows that floral architecture influences the selection of floral host resources used to provide nutrients to parasitoids in cropping systems. Parasitoid foraging performance was evaluated using real and artificial flowers which varied in degree of nectar accessibility for two eulophid parasitoids, Edovum puttleri Grissell and Pediobius foveolatus Crawford. Comparisons were made of searching performance on artificial flowers with nectars that were either scented (made from 1:1 honey‐water solution) or scentless (made from 1 m sucrose solution) and differences in head widths were compared with corolla apertures. Our results showed a disparity in the ability of E. puttleri and P. foveolatus to gain access to nectar from particular types of floral architectures. E. puttleri fed efficiently only from flowers with exposed nectaries while P. foveolatus foraged efficiently from flowers having either exposed nectaries or nectaries partially obstructed by petals and stamens. Neither wasp species could forage on flowers with cup‐ or tube‐shaped corollas because their heads are wider than the floral apertures. E. puttleri's foraging performance decreased as nectar inaccessibility increased in the artificial flowers, while P. foveolatus' foraging performance was uniform among the different artificial flowers. This indicates that E. puttleri has less propensity to search small openings for nectar than does P. foveolatus. The foraging success of both E. puttleri and P. foveolatus on artificial flowers was lower when 1 M sucrose solution was used as an artificial nectar rather than honey‐water solution, indicating that the wasps were stimulated and attracted by the nectar odor. Our systematic evaluation of floral architecture with respect to parasitoid foraging ability has enabled us to predict which types of flowers would serve as suitable floral host plants for parasitoids in the field. That is, only flowers with nectaries that are completely exposed would function as suitable floral host plants for E. puttleri, while P. foveolatus could forage on flowers with either exposed or partially exposed nectaries. Examples of potentially suitable floral hosts suggested from our study include dill (Anethum graveolens L.) and fennel (Foeniculum vulgare L.) for both E. puttleri and P. foveolatus and coriander (Coriandrum sativa L.) for P. foveolatus.
Temporal and spatial changes in aphid and parasitoid populations following applications of deltamethrin in winter wheat
Authors: Longley Martin , Jepson Paul C. , Izquierdo Josep , Sotherton Nicolas
Published: October 2003

The spatial and temporal effects of the pyrethroid insecticide, deltamethrin, on populations of cereal aphids and their primary parasitoids and hyperparasitoids were investigated in a large scale field experiment in winter wheat. Four hectare plots were treated at the recommended field concentration or a reduced concentration representing one twentieth of field rate. A control plot was left unsprayed. Invertebrate populations were sampled at sites within a grid layout covering the whole plots, enabling the use of geostatistical analysis. Hymenopteran populations were monitored using transparent sticky traps and suction sampling. Aphid populations were recorded by visual counts. Monitoring continued for 36 days after treatment. The full rate deltamethrin treatment resulted in initial reductions of aphid populations by 78%. Primary parasitoid and hyperparasitoid populations were reduced in suction samples by 90% and 47% respectively, when corrected for control fluctuations. The reduced deltamethrin concentration caused reductions of aphid, primary parasitoid and hyperparasitoid populations of 40, 60 and 54% respectively. Aphid population recovery over the full rate plot occurred slowly and in a ‘patchy’ manner following treatment. No significant reinvasion gradients were detected. Aphid population density recovered more rapidly in the reduced rate treatment; with initial evidence for increased densities at the plot centre. Significant patterns of reinvasion were initially detected for both groups of Hymenoptera in the full rate treatment, suggesting that reinvasion of the sprayed area was taking place from untreated surrounding reservoirs. It was concluded that experiments that examine pesticide impacts within small plots will lead to underestimates of effects on dispersive groups including parasitic Hymenoptera.
Combined effects of night‐time temperature and allelochemicals on performance of a generalist insect herbivore
Authors: Stamp Nancy E. , Osier Tod L.
Published: October 2003

To assess the pattern of temperature influencing the effect of allelochemicals on growth of insect herbivores and to examine the potential effect of warmer nights due to global warming, we examined the simultaneous effects of allelochemicals and warmer night‐time temperatures on an insect herbivore (Spodoptera exigua; Lepidoptera: Noctuidae). Dietary chlorogenic acid, rutin and tomatine levels reflected those occurring naturally in the leaves of tomato, a hostplant of this herbivore. We compared the effects of four thermal regimes having a daytime temperature of 26 °C, with the night‐time temperature increased from 14 to 26 °C by increments of 4 °C. The effect of a particular allelochemical on developmental rate was similar among the four thermal regimes. Chlorogenic acid and tomatine each reduced final larval weight, but there was no effect of night‐time temperature. In contrast, rutin had no effect on final weight, whereas final weight declined with increasing night‐time temperature. Night‐time temperature did not influence amount eaten. Larvae ate less when chlorogenic acid or tomatine was in the diet. For each allelochemical, there were no allelochemical by thermal regime interactions. In addition, we compared the effects of allelochemicals and the thermal regime of 26:14 °C and constant 20 °C, which was the average temperature of the 26:14 °C regime. Developmental rate was lower at the constant 20 °C regime, chlorogenic acid and tomatine each depressed developmental rate, and there were no allelochemical by thermal regime interactions. Thus, regardless of the specific allelochemical or amount, the pattern of response at the fluctuating regime was similar to that at the constant temperature. In contrast, comparison of the thermal regime of 26:22 °C and constant 24 °C, which was the average temperature of the 26:22 °C regime, showed several allelochemical by thermal regime interactions. At the 26:22 °C regime, developmental rate was disproportionatly higher at the maximal rutin concentration compared to that at constant 24 °C. At the constant 24 °C, final larval mass was disproportionately lower at the moderate tomatine concentration compared to that at the 26:22 °C regime. Because these results differ from that of other studies examining another species, it appears that the response to incremental changes in night‐time temperature will reflect the allelochemicals and insect species tested. The contrast between the constant 24 °C and 26:22 °C regimes indicates that even small fluctuations (±2 °C ) in temperature over 24 h can yield differences in the response to an allelochemical.
Insect feeding on cucumber mediated by rhizobacteria‐induced plant resistance
Authors: Zehnder Geoffrey , Kloepper Joseph , Tuzun Sadik , Yao Changbin , Wei Gang , Chambliss Oyette , Shelby Richard
Published: October 2003

Select strains of plant growth‐promoting rhizobacteria (PGPR) were evaluated in greenhouse experiments with cucumber for induction of resistance against cucumber beetle (Diabrotica undecimpunctata howardi Barber) feeding and the beetle‐transmitted cucurbit wilt disease. When beetles were given a choice between PGPR‐treated and nontreated cucumber, their feeding on stems and cotyledons and the severity of wilt symptoms were significantly lower on PGPR‐treated plants. HPLC analysis demonstrated that cotyledons from PGPR‐treated plants contained significantly lower concentrations of the cucumber beetle feeding stimulant cucurbitacin than nontreated plants. These results suggest that a mechanism for PGPR‐induced resistance against cucumber beetle feeding may involve a change in the metabolic pathway for cucurbitacin synthesis.
Regulation of apple leaf aldose-6-phosphate reductase activity by inorganic phosphate and divalent cations
Authors: Zhou Rui , Sicher Richard C. , Cheng Lailiang , Quebedeaux Bruno
Published: October 2003

Aldose-6-phosphate reductase (A6PR), a key enzyme in sorbitol biosynthesis, has been purified to apparent homogeneity from fully developed apple (Malus domestica Borkh. cv. Gala) leaves. Inorganic phosphate inhibited A6PR by decreasing the maximum velocity of the enzyme and by increasing the Km for the substrate, glucose-6-phosphate (Glc6P). Divalent cations including Ca2+, Mg2+, Zn2+ and Cu2+ altered A6PR activity. Effects of Ca2+ and Mg2+ on A6PR activity were dependent upon both the metal ion concentration and the concentration of Glc6P. The activity of A6PR was increased by 0.5–5 mM Ca2+ or Mg2+ when Glc6P concentration was below 10 mM. However, these same metal ions decreased A6PR activity at greater Glc6P concentrations or in the presence of higher metal ion concentrations. A6PR displayed Michaelis–Menten kinetics either in the presence or absence of 2.5 mM MgCl2, but the apparent Km for Glc6P decreased from 11.3 mM for the control to 5.1 mM in the presence of 2.5 mM MgCl2 in the assay mixture. By contrast, Zn2+ and Cu2+ dramatically inactivated A6PR activity. A6PR activity was decreased approximately 50 and 70%, respectively, when the enzyme was pre-incubated with 2 mM Zn2+ or Cu2+ for 60 min at room temperature. This inactivation was partially reversed by dialysis or by chelation with 20 mM EDTA. NADPH and NADP+, which are substrates for A6PR in the oxidative and reductive directions, respectively, partially protected A6PR from inactivation by Zn2+. The above results suggest that both Mg2+ and Ca2+ were mixed-type, non-essential activators of A6PR that decreased the Km for sugar-phosphates but lowered the overall Vmax. The physiological significance of these findings is also discussed.
Variation in chloroplast small heat-shock protein function is a major determinant of variation in thermotolerance of photosynthetic electron transport among ecotypes of Chenopodium album
Authors: Barua Deepak , Downs Craig A. , Heckathorn Scott A.
Published: October 2003

Chloroplast small (low-molecular-weight) heat-shock proteins (csHsps) can protect photosynthetic electron transport (Pet), and quantitative variation in csHsps is correlated with thermotolerance of net photosynthesis and Photosystem II. However, the functional (i.e. protective) consequence of natural variation in csHsps is unknown. To investigate this, we used an in vitro assay to determine the contribution of csHsps to the tolerance of Pet to high temperatures in five ecotypes of Chenopodium album collected from habitats ranging from cool to warm, and we partitioned total Pet thermotolerance into basal and induced Pet components (without and with a pre-heat treatment, respectively, to induce csHsps). The ecotypes varied in total Pet thermotolerance and this was correlated with habitat temperature. Variation in total Pet thermotolerance was associated primarily with variation in induced Pet thermotolerance, and not with basal Pet thermotolerance. Variation in induced Pet was highly correlated with csHsp protection of Pet. Variation in csHsp function was associated with variation in csHsp content among ecotypes. These results are the first to demonstrate the direct functional consequences for natural variation in Hsps in plants, and show that functional variation is associated with evolutionary adaptation to specific habitats among ecotypes.
Genetic transformation in commercial Tasmanian cultivars of opium poppy, Papaver somniferum, and movement of transgenicpollen in the field
Authors: Chitty Julie A. , Allen Robert S. , Fist Anthony J. , Larkin Philip J.
Published: October 2003

We report a new transformation protocol for the pharmaceutically important opium poppy, Papaver somniferum L.; the protocol allows transformation for the first time of high yielding commercial cultivars. The method involves Agrobacterium tumefaciens infection of hypocotyl explants, followed by the production of antibiotic- or herbicide-resistant embryogenic callus and the subsequent induction of somatic embryos and plants. Key elements of the improvement are the use of buffering agents to stabilise medium pH and bottom-cooling of the cultures. Transformation was verified by PCR and Southern blot hybridisation. Transcription of transgenes was confirmed by RT–PCR and product sequencing. Expression of transgenes was detected by histochemical GUS staining, phosphinothricin acetyltransferase (PAT) enzyme assays for bar and pat genes, and western analysis of transgenic sunflower seed albumin protein. Expression of various transgenes was detected in stem, leaf, seed, capsule and latex. The pat gene was demonstrated to be stably inherited to the T2 generation and to confer phosphinothricin (PPT) herbicide resistance. Most T0 plants showed normal morphology, were self-fertile and the transgenes displayed the expected Mendelian segregation. The percentage of explants producing somatic embryos that developed into plantlets able to be transplanted to soil, ranged from 6–11% in two Tasmanian cultivars.A field trial using pat transgenic plants was designed to estimate the frequency of hybridisation at various distances into buffer rows of non-transgenic poppies and to related weed species, P. somniferum spp. setigerum and P. dubium. The frequency of hybridisation to completely compatible poppy fell sharply with distance, being 2.6% at 20 cm, 2.13% at 0.5 m and falling to 0% at 2.5 and 5 m. No hybridisation could be detected to two weed species under open pollination conditions, including the compatible P. somniferum spp. setigerum, when grown as close as 20 cm, despite flowering at the same time as the transgenic plants in the presence of foraging bees.