Characterization of Phytophthora capsici from Michigan Surface Irrigation Water

Phytophthora capsici infects cucurbitaceous and solanaceous crops worldwide. In free water, P. capsici sporangia release zoospores that may be disseminated by moving surface water. Surface irrigation sources (river system, ponds, and ditches) in three Michigan counties with a history of P. capsici-susceptible crop production were monitored for the pathogen during four growing seasons (2002 to 2005). Pear and cucumber baits were suspended in water at monitoring sites for 3- to 7-day intervals and water temperature was recorded. Baits were washed and lesions were excised and cultured on water agar amended with rifampicin and ampicillin. P. capsici was detected at monitoring sites in multiple years, even when non-host crops were planted nearby. Recovered isolates (N = 270) were screened for sensitivity to the fungicide mefenoxam and characterized for mating type (MT). P. capsici isolates resistant to mefenoxam were common in water sources from southwest and southeast Michigan. Most monitoring sites yielded isolates of a 1:1 ratio of A1:A2 MTs. Amplified fragment length polymorphism analysis of select isolates from 2002 to 2004 indicated a lack of similarity groups persisting over time and in specific geographical locations. Data suggest that P. capsici did not overwinter in any of the surface water sources monitored. Water temperatures were correlated to positive P. capsici detection from all monitoring sites. The frequent detection of P. capsici in surface water used for irrigation in the primary vegetable growing regions in Michigan suggests that this is an important means of pathogen dissemination.

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Surface-water resources of the Yobe River system, Northern Nigeria, 1963-68

10.3133/25251 ◽

1969 ◽

Keyword(s):

Surface Water ◽

Water Resources ◽

River System ◽

Northern Nigeria ◽

Surface Water Resources

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Effects of cereal rye seeding rate on waterhemp (Amaranthus tuberculatus) emergence and soybean growth and yield

Weed Technology ◽

10.1017/wet.2021.28 ◽

2021 ◽

pp. 1-25

Author(s):

Mandy Bish ◽

Brian Dintelmann ◽

Eric Oseland ◽

Jacob Vaughn ◽

Kevin Bradley

Keyword(s):

Crop Production ◽

Production Systems ◽

Soil Seed Bank ◽

Linear Regression Analysis ◽

Growth And Yield ◽

Seeding Rate ◽

Early Season ◽

Cereal Rye ◽

Herbicide Resistant ◽

Growing Seasons

Abstract The evolution of herbicide-resistant weeds has resulted in the necessity to integrate non-chemical control methods with chemicals for effective management in crop production systems. In soybean, control of the pigweed species, particularly herbicide-resistant waterhemp and Palmer amaranth, have become predominant concerns. Cereal rye planted as a winter cover crop can effectively suppress early-season weed emergence in soybean, including waterhemp, when planted at a rate of 123 kg ha−1. The objectives of this study were to determine the effects of different cereal rye seeding rates (0, 34, 56, 79, 110, and 123 kg ha−1) on early-season waterhemp suppression and soybean growth and yield. Soybean was planted into fall-seeded cereal rye, which was terminated within four days of soybean planting. The experiment was conducted over the 2018, 2019, and 2020 growing seasons in Columbia, Missouri. Effects of cereal rye on early-season waterhemp suppression varied by year and were most consistent at 56 kg ha−1 or higher seeding rates. Linear regression analysis of cereal rye biomass, height, or stand at soybean planting showed inverse relationships with waterhemp emergence. No adverse effects to soybean growth or yield were observed at any of the cereal rye seeding rates relative to plots that lacked cereal rye cover. Result differences among the years suggest that the successfulness of cereal rye on suppression of early-season waterhemp emergence is likely influenced by the amount of waterhemp seed present in the soil seed bank.

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Preliminary Screening for Microplastic Concentrations in the Surface Water of the Ob and Tom Rivers in Siberia, Russia

Sustainability ◽

10.3390/su13010080 ◽

2020 ◽

Vol 13 (1) ◽

pp. 80

Author(s):

Yulia A. Frank ◽

Egor D. Vorobiev ◽

Danil S. Vorobiev ◽

Andrey A. Trifonov ◽

Dmitry V. Antsiferov ◽

...

Keyword(s):

Surface Water ◽

Arctic Ocean ◽

River System ◽

The Arctic ◽

Preliminary Screening ◽

Freshwater Systems ◽

Ob River ◽

The Arctic Ocean ◽

Abundance And Diversity ◽

Blank Spot

To date, the largest Russian rivers discharging to the Arctic Ocean remain a “blank spot” on the world map of data on the distribution of microplastics in freshwater systems. This study characterizes the abundance and morphology of microplastics in surface water of the Ob River and its large tributary, the Tom River, in western Siberia. The average number of particles for the two rivers ranged from 44.2 to 51.2 items per m3 or from 79.4 to 87.5 μg per m3 in the Tom River and in the Ob River, respectively. Of the recovered microplastics, 93.5% were less than 1 mm in their largest dimension, the largest group (45.5% of total counts) consisted of particles with sizes range 0.30–1.00 mm. Generally, microfragments of irregular shape were the most abundant among the Ob and Tom samples (47.4%) and exceeded microfibers (22.1%), microfilms (20.8%), and microspheres (9.74%) by average counts. Results from this study provide a baseline for understanding the scale of the transport of microplastics by the Ob River system into the Arctic Ocean and add to currently available data on microplastics abundance and diversity in freshwater systems of differing global geographic locations.

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Perceived agricultural runoff impact on drinking water

Journal of Water and Health ◽

10.2166/wh.2014.212 ◽

2014 ◽

Vol 12 (3) ◽

pp. 484-491 ◽

Cited By ~ 2

Author(s):

Andrea Crampton ◽

Angela T. Ragusa

Keyword(s):

Water Quality ◽

Drinking Water ◽

Surface Water ◽

Agricultural Runoff ◽

Water Sources ◽

Urban Residents ◽

Agricultural Activity ◽

Rural Residents ◽

Management Measures ◽

Agricultural Contaminants

Agricultural runoff into surface water is a problem in Australia, as it is in arguably all agriculturally active countries. While farm practices and resource management measures are employed to reduce downstream effects, they are often either technically insufficient or practically unsustainable. Therefore, consumers may still be exposed to agrichemicals whenever they turn on the tap. For rural residents surrounded by agriculture, the link between agriculture and water quality is easy to make and thus informed decisions about water consumption are possible. Urban residents, however, are removed from agricultural activity and indeed drinking water sources. Urban and rural residents were interviewed to identify perceptions of agriculture's impact on drinking water. Rural residents thought agriculture could impact their water quality and, in many cases, actively avoided it, often preferring tank to surface water sources. Urban residents generally did not perceive agriculture to pose health risks to their drinking water. Although there are more agricultural contaminants recognised in the latest Australian Drinking Water Guidelines than previously, we argue this is insufficient to enhance consumer protection. Health authorities may better serve the public by improving their proactivity and providing communities and water utilities with the capacity to effectively monitor and address agricultural runoff.

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Summer Watering Patterns of Mule Deer in the Great Basin Desert, USA: Implications of Differential Use by Individuals and the Sexes for Management of Water Resources

The Scientific World JOURNAL ◽

10.1100/2012/846218 ◽

2012 ◽

Vol 2012 ◽

pp. 1-9 ◽

Cited By ~ 9

Author(s):

Andrew V. Shields ◽

Randy T. Larsen ◽

Jericho C. Whiting

Keyword(s):

Water Resources ◽

Great Basin ◽

Mule Deer ◽

Free Water ◽

Water Sources ◽

Limiting Factor ◽

Mountain Range ◽

Great Basin Desert ◽

Water Developments ◽

Conservation And Management

Changes in the abundance and distribution of free water can negatively influence wildlife in arid regions. Free water is considered a limiting factor for mule deer (Odocoileus hemionus) in the Great Basin Desert. Consequently, a better understanding of differential use of water by individuals and the sexes could influence the conservation and management of mule deer and water resources in their habitats. We deployed remote cameras at all known water sources (13 wildlife water developments and 4 springs) on one mountain range in western Utah, USA, during summer from 2007 to 2011 to document frequency and timing of water use, number of water sources used by males and females, and to estimate population size from individually identified mule deer. Male and female mule deer used different water sources but visited that resource at similar frequencies. Individual mule deer used few water sources and exhibited high fidelity to that resource. Wildlife water developments were frequently used by both sexes. Our results highlight the differing use of water sources by sexes and individual mule deer. This information will help guide managers when siting and reprovisioning wildlife water developments meant to benefit mule deer and will contribute to the conservation and management of this species.

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Legionella and Public Water Supplies

Water Science & Technology ◽

10.2166/wst.1988.0259 ◽

1988 ◽

Vol 20 (11-12) ◽

pp. 5-10 ◽

Cited By ~ 36

Author(s):

J. S. Colbourne ◽

P. J. Dennis ◽

R. M. Trew ◽

C. Berry ◽

G. Vesey

Keyword(s):

Surface Water ◽

Heat Shock ◽

Distribution Systems ◽

Potable Water ◽

Water Sources ◽

Water Supplies ◽

Indirect Immunofluorescent Assay ◽

Water Mains ◽

Legionnaires Disease ◽

Indirect Immunofluorescent

A survey for legionella in public water supplies in England failed to detect culturable L.pneumophila in all but samples from taps in buildings; however, the organism was detected in underground and surface water sources and distribution systems using an indirect immunofluorescent assay (IFA) to L.pneumophila serogroup 1. Culturability was related to water temperatures above 20°C. In water mains L.pneumophila was associated with biofilms or sediment. Non-culturable L.pneumophila detected in potable waters by IFA were recovered by heat shock experiments demonstrating their viability. Although the strain found in potable water is rarely asociated with disease, monoclonal expression, a virulence marker, was altered by heat shock. These findings have implications for the prevention of legionellosis and may explain the sporadic nature of legionnaires disease in the community.

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Insects associated with sesame (Sesamun indicum L.) and the impact of insect pollinators on crop production

Pesticidi i fitomedicina ◽

10.2298/pif1202117m ◽

2012 ◽

Vol 27 (2) ◽

pp. 117-129 ◽

Cited By ~ 1

Author(s):

Farag Mahmoud

Keyword(s):

Crop Production ◽

Digital Camera ◽

Insect Species ◽

Pitfall Traps ◽

Experimental Site ◽

Insect Pollination ◽

Growing Seasons ◽

Pass Through ◽

The Impact ◽

Weight Number

A survey of insects associated with sesame, Sesamun indicum L. (Pedaliaceae) was conducted at the Agriculture Research Farm of The Faculty of Agriculture, University of Suez Canal during the growing seasons 2010 and 2011. All different insect species found on the experimental site were collected for identification. Sampling was done once a week and three times a day. Three methods were used to collect insects from the sesame plants (a sweep net, pitfall traps, digital camera and eye observation). A total of 31 insect species were collected and properly identified during the survey. Insects recorded on the plants were divided into four groups, true pollinators (Hymenoptera), other pollinators (Diptera, Coleoptera and Lepidoptera), pests (Orthoptera, Odonata, Hemiptera and Homoptera) and natural enemies (Coleoptera, Hymenoptera, Neuroptera and Dictyoptera). For studying the impact of insect pollination on sesame production, the experiment was divided in two: opened and non-opened pollination of sesame. 50 plants from nonopened pollination were covered with a perforated paper bag to allow the air to pass through and to prevent insects from approaching the plants. Quantitative and qualitative parameters were measured as follows: pod weight, number of seeds in each pod, weight of 1000 seeds, germination (%), seedlings vigour and oil content (%). Results clearly demonstrate that the opened pollination improved the crop production.

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