Evaluation of organic,synthetic and physical insecticides for the control of horse chestnut leaf miner (Cameraria ohridella)

Two separate trials during 2007 and 2008 were conducted using containerized white flowering horse chestnut trees (Aesculus hippocastanum L.) to assess the efficacy of a range of insecticides applied at three different times during a growing season against the insect pest, horse chestnut leaf miner (Cameraria ohridella Deschka and Dimic; HCLM). Insecticides were timed to coincide with the emergence of the adult moth, the target organism. A conventional synthetic insecticide (deltamethrin) used within the UK for HCLM control was included for comparison. A marked impact of insecticide type and frequency of application on HCLM severity was recorded. The effectiveness of each insecticide on mean number of HCLM mines per leaf and percent HCLM larvae/pupae mortality increased when applied at increasing frequencies, i.e. three sprays provided a higher degree of control than two sprays while two sprays provided a higher degree of control than one spray. Limited efficacy as HCLM protectant compounds was demonstrated when the insecticides pyrethrum and soap were applied, irrespective of number of applications. The synthetic insecticide deltamethrin and insect growth regulator diflubenzuron provided the greatest degree of HCLM control. In some instances two foliar sprays provided 100% HCLM control. Efficacy of remaining insecticides based on reduction of HCLM mines per leaf after three sprays averaged across both the 2007 and 2008 trials was in the order silicon dioxide > alginate/polysaccharide combination > organic plant extract > spray oil. Results show commercially registered insecticides exist that provide growing season control of HCLM provided two sprays are applied.     

Guatemela: preliminary zircon ages from central cordillera

Concordia resolution of uranium-lead analyses of zircons from rocks of the Guatemalan Cordillera indicates a period of plutonism, and perhaps metamorphism, in late Paleozoic times (345 +/- 20 million years). Gneisses of the Chuacus Series yield an age of 1075 +/- 25 million years which may be either the age of a source terrain for the original sediments, or the age of principal metamorphism. Zircons from a Paleozoic granite intruding the gneisses appear to contain inherited or contaminating material acquired during the process of magma generation or emplacement, or both.     

Reproducibility of a short semi-quantitative food group questionnaire and its performance in estimating nutrient intake compared with a 7-day diet diary in the Million Women Study

OBJECTIVES: To assess the short- and long-term reproducibility of a short food group questionnaire, and to compare its performance for estimating nutrient intakes in comparison with a 7-day diet diary. DESIGN: Participants for the reproducibility study completed the food group questionnaire at two time points, up to 2 years apart. Participants for the performance study completed both the food group questionnaire and a 7-day diet diary a few months apart. Reproducibility was assessed by kappa statistics and percentage change between the two questionnaires; performance was assessed by kappa statistics, rank correlations and percentages of participants classified into the same and opposite thirds of intake. SETTING: A random sample of participants in the Million Women Study, a population-based prospective study in the UK. SUBJECTS: In total, 12 221 women aged 50-64 years. RESULTS: In the reproducibility study, 75% of the food group items showed at least moderate agreement for all four time-point comparisons. Items showing fair agreement or worse tended to be those where few respondents reported eating them more than once a week, those consumed in small amounts and those relating to types of fat consumed. Compared with the diet diary, the food group questionnaire showed consistently reasonable performance for the nutrients carbohydrate, saturated fat, cholesterol, total sugars, alcohol, fibre, calcium, riboflavin, folate and vitamin C. CONCLUSIONS: The short food group questionnaire used in this study has been shown to be reproducible over time and to perform reasonably well for the assessment of a number of dietary nutrients.     

Wheat flour protein content and water absorption analysis in a doubled haploid population

A wheat×maize induced doubled haploid population that segregates at the Awned locus for awned and awnless phenotypes were studied at two field sites using a genetic linkage map. Interval QTL analysis indicated that significant QTLs for wheat flour water absorption and protein content were located on a linkage group associated with the morphological marker, awns. The QTL peak for flour water absorption was located at the Awned locus (B1, 5AL), whilst the QTL peak for protein content was located nearby, 10.1 cm away from the Awned locus. The locations of those QTL were confirmed by analysing data from two independent field trials conducted under different environment conditions. The QTL identified for water absorption controlled 12% and 11% of the observed variance at the two field trials, whilst for flour protein content the QTL explained 7% and 19% of the variance respectively. Variance component analysis indicated that the QTL for water absorption controlled approximately 14.8–25.0% and 13.6–23% of the genetic variance at the two sites studied (Roma and Jimbour) whilst the QTL for protein content explained between 12.8% and 30.4% of the genetic variance at Roma and 34.7–82.6% at Jimbour. Cross-site analysis with composite interval mapping approach resulted in significant LOD values of 6.12 and 9.94 for water absorption and protein content, respectively. The QTL for water absorption was independent from the hardness locus.     

Applications of pedigree-based genome mapping in wheat and barley breeding programs

The aim of the pedigree-based genome mapping project is to investigate and develop systems for implementing marker assisted selection to improve the efficiency of selection and increase the rate of genetic gain in breeding programs. Pedigree-based whole genome marker application provides a vehicle for incorporating marker technologies into applied breeding programs by bridging the gap between marker–trait association and marker implementation. We report on the development of protocols for implementation of pedigree-based whole genome marker analysis in breeding programs within the Australian northern winter cereals region. Examples of applications from the Queensland DPI&F wheat and barley breeding programs are provided, commenting on the use of microsatellites and other types of molecular markers for routine genomic analysis, the integration of genotypic, phenotypic and pedigree information for targeted wheat and barley lines, the genomic impacts of strong selection pressure in case study pedigrees, and directions for future pedigree-based marker development and analysis.     

Water uptake by scots pine sapwood,and its restriction by the use of water repellents

Summary Water in contact with wood surfaces is able to penetrate into the cellular structure by three routes: 1. As liquid water into cell lumena, by capillarity. — 2. As water vapour, by diffusion into cell lumena. — 3. As bound water, by diffusion within the cell wall.Transport from cell lumena into adjacent cell walls occurs rapidly by diffusion. In Scots pine (Pinus sylvestris) sapwood, it is shown that transport over short distances occurs much more rapidly by capillarity than by either of the diffusion processes. Treatment of wood with resin/wax water repellent formulations greatly reduces the rate of water flow due to capillarity and hence significantly cuts down the rate of dimensional change of specimens exposed to wet conditions.Swelling rates due to vapour phase and bound water diffusion were measured experimentally, and these data were used to predict the water sorption rates for specimens treated with a theoretically perfect water repellent, viz. that which excludes all liquid water.It was found experimentally that specimens immersed in water, after treatment with resin/wax water repellents, swelled more rapidly than predicted by the above procedure. This more rapid swelling is probably due to a certain amount of liquid water flow made possible by displacement of the hydrophobic film from cell wall surfaces (preferential wetting). It is suggested that the use of hydrophobic agents bonded chemically to the cell wall may be necessary to attain optimum water repellent effectiveness.