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The effects of biological treatments with PlantShield®, Prestop®, Quadra 136, RootShield®, and S33 (Rhodosporidium diobovatum) and chemical treatment with Decree® applied as a preventive or curative sprays on stem canker caused by Botrytis cinerea on tomato plants grown in sawdust were studied under near-commercial greenhouse conditions. Prestop® and Decree®, applied as preventive or curative sprays, PlantShield® applied as curative spray, and S33 and Q-136 applied as preventive or preventive plus one spray to wounded surface provided season-long protection from B. cinerea stem canker. These treatments also increased fruit yield and decreased the number of dead plants compared with the inoculated control. 相似文献
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A psychological test battery comprising reasoning ability, name and number checking, letter cancellation and associative recall was administered to a group of 70 student nurses at 2-hr intervals from 0800 to 2000 to determine if their performance varied at different times of day. Simultaneously, their oral temperature was recorded. A 7 x 7 latin square design was utilized, and latin square repeated measure analysis of variance was employed. The results indicated variations in oral temperature as the day advanced. While accuracy of performance in cognitive tasks was found to be superior during the early morning, noon or early evening hours, the speed of performance was highest during the period from late-morning to late-evening. 相似文献
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Michelle van der Bank F. H. van der Bank B. -E. van Wyk 《Plant Systematics and Evolution》1999,219(1-2):27-38
We have tested the hypothesis that reseeding is a plesiomorphic character state and that sprouting is a derived state inAspalathus linearis, and that the latter is an adaptation to ensure fire-survival in a fireprone environment. Samples of five seeder and four sprouter populations of A.linearis were examined by horizontal starch gel electrophoresis to assess the amount of genetic differentiation within and between sprouting and seeding populations, and to determine the extent of gene flow between the populations. Leaf extracts were surveyed for ten enzymes and gene products revealed genetic variation at 13 (76%) of 17 protein coding loci. Allele frequency differences were found between sprouting and seeding populations and genetic distance values show that the sprouters are grouped separate from the seeders, thus providing support for the morphological data on which the above mentioned hypothesis is based. It is evident that evolution operates at the population level inA. linearis. 相似文献
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Stefan Schoombie Janine Schoombie Christiaan W. Brink Kim L. Stevens Christopher W. Jones Michelle M. Risi Peter G. Ryan 《Journal of Field Ornithology》2019,90(4):361-372
The use of miniaturized video cameras to study the at‐sea behavior of flying seabirds has increased in recent years. These cameras allow researchers to record several behaviors that were not previously possible to observe. However, video recorders produce large amounts of data and videos can often be time‐consuming to analyze. We present a new technique using open‐source software to extract bank angles from bird‐borne video footage. Bank angle is a key facet of dynamic soaring, which allows albatrosses and petrels to efficiently search vast areas of ocean for food. Miniaturized video cameras were deployed on 28 Wandering Albatrosses (Diomedea exulans) on Marion Island (one of the two Prince Edward Islands) from 2016 to 2018. The OpenCV library for the Python programming language was used to extract the angle of the horizon relative to the bird’s body (= bank angle) from footage when the birds were flying using a series of steps focused on edge detection. The extracted angles were not significantly different from angles measured manually by three independent observers, thus being a valid method to measure bank angles. Image quality, high wind speeds, and sunlight all influenced the accuracy of angle estimates, but post‐processing eliminated most of these errors. Birds flew most often with cross‐winds (58%) and tailwinds (39%), resulting in skewed distributions of bank angles when birds turned into the wind more often. Higher wind speeds resulted in extreme bank angles (maximum observed was 94°). We present a novel method for measuring postural data from seabirds that can be used to describe the fine‐scale movements of the dynamic‐soaring cycle. Birds appeared to alter their bank angle in response to varying wind conditions to counter wind drift associated with the prevailing westerly winds in the Southern Ocean. These data, in combination with fine‐scale positional data, may lead to new insights into dynamic‐soaring flight. 相似文献
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Rachael V. Gallagher Lesley Hughes Michelle R. Leishman Peter D. Wilson 《Biological invasions》2010,12(12):4049-4063
Potential interactions between climate change and exotic plant invasions may affect areas of high conservation value, such
as land set aside for the protection of endangered species or ecological communities. We investigated this issue in eastern
Australia using species distribution models for five exotic vines under climate regimes for 2020 and 2050. We examined how
projected changes in the distribution of climatically suitable habitat may coincide with the remaining remnants of an endangered
ecological community—littoral rainforests—in this region. The number of known infestations of each weed in tropical, subtropical
and temperate areas was used to assess the likelihood of further expansion into areas projected to provide suitable habitat
under future conditions. Littoral rainforest reserves were consistently predicted to provide bioclimatically suitable habitat
for the five vines examined under both current and future climate scenarios. We explore the consequences and potential strategies
for managing exotic plant invasions in these protected areas in the coming decades. 相似文献
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