Search Results - "WESTERMAN, P.R"

Density‐independent reproductive success of the hemiparasitic plant Striga hermonthica, despite positive and negative density‐dependent phases by Westerman, P.R., Hemerik, L., van der Werf, W., Stomph, T.J.

“…The hemiparasite Striga hermonthica is a major constraint to smallholder farmer livelihoods and food security in sub‐Saharan Africa. A better understanding of…”
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Relative importance of vertebrates and invertebrates in epigeaic weed seed predation in organic cereal fields by Westerman, P.R, Hofman, A, Vet, L.E.M, van der Werf, W

“…Exclosure trials were conducted in four organic cereal fields in The Netherlands in 1999 and 2000 to determine the relative importance of vertebrates and…”
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Spatial and temporal patterns of carabid activity-density in cereals do not explain levels of predation on weed seeds by Saska, P, van der Werf, W, de Vries, E, Westerman, P R

“…Seed predation is an important component of seed mortality of weeds in agro-ecosystems, but the agronomic use and management of this natural weed suppression…”
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Influence of seed density and aggregation on post-dispersal weed seed predation in cereal fields by Marino, Paul C., Westerman, P.R., Pinkert, C., Werf, W. van der

“…The importance of density dependence, aggregation and background density of seeds on intensity of seed predation in cereal fields were examined in central…”
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Long-term management of the parasitic weed Striga hermonthica: Strategy evaluation with a population model by Westerman, P.R., van Ast, A., Stomph, T.J., van der Werf, W.

“…To increase sorghum yields in areas in Africa that are heavily infested with the root parasite Striga hermonthica, crop varieties are being bred whose roots…”
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Exploring the scope for improving biocontrol of black vine weevil, Otiorhynchus sulcatus, with Heterorhabditis spp. at low temperatures: A simulation study by Westerman, P.R., van der Werf, W.

“…Control success with heterorhabditid nematodes varies with nematode species, isolate, production and storage conditions, and environmental conditions after…”
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Agronomic and Economic Performance Characteristics of Conventional and Low-External-Input Cropping Systems in the Central Corn Belt by Liebman, M, Gibson, L.R, Sundberg, D.N, Heggenstaller, A.H, Westerman, P.R, Chase, C.A, Hartzler, R.G, Menalled, F.D, Davis, A.S, Dixon, P.M

“…We conducted a 9-ha field experiment near Boone, IA, to test the hypothesis that yield, weed suppression, and profit characteristics of low-external-input…”
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Are many little hammers effective? Velvetleaf (Abutilon theophrasti) population dynamics in two- and four-year crop rotation systems by Westerman, Paula R., Liebman, Matt, Menalled, Fabián D., Heggenstaller, Andrew H., Hartzler, Robert G., Dixon, Philip M.

“…To improve understanding of relationships between crop diversity, weed management practices, and weed population dynamics, we used data from a field experiment…”
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Integrating measurements of seed availability and removal to estimate weed seed losses due to predation by Westerman, Paula R., Liebman, Matt, Heggenstaller, Andrew H., Forcella, Frank

“…To better understand seed predation and enhance weed seed losses in arable fields, we developed a conceptual model that integrates seed dispersal, seed burial,…”
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Annual Losses of Weed Seeds Due to Predation in Organic Cereal Fields by Westerman, P. R., Wes, J. S., Kropff, M. J., Van Der Werf, W.

“…1. Post-dispersal seed losses in annual arable weed species are poorly quantified, but may be of significance for natural population control, especially if…”
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The significance of a grassy field boundary for the spatial distribution of carabids within two cereal fields by Saska, Pavel, Vodde, Maarten, Heijerman, Theodoor, Westerman, Paula, van der Werf, Wopke

“…This paper investigated how distance from the field edge affects overall activity-density, species richness and distribution of individual carabid (Coleoptera:…”
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Burial rates of surrogate seeds in arable fields by WESTERMAN, P.R, DIXON, P.M, LIEBMAN, M

“…The probability of seed consumption by surface-dwelling predators depends on the duration of seed exposure on the soil surface. We investigated seed burial…”
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Weed seed predation in a phenologically late crop by WESTERMAN, P R, LUIJENDIJK, C D, WEVERS, J D A, VAN DER WERF, W

“…Westerman PR, Luijendijk CD, Wevers JDA & Van DerWerf W (2011). Weed seed predation in a phenologically late crop. Weed Research51, 157–164. Summary Seed…”
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Over-winter predation of Abutilon theophrasti and Setaria faberi seeds in arable land by WILLIAMS, C.L, LIEBMAN, M, WESTERMAN, P.R, BORZA, J, SUNDBERG, D, DANIELSON, B

“…To improve understanding of over-winter weed seed predation in arable fields, we used data from winter exclosure trials to determine the amount of predation…”
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Aggregation of Entomopathogenic Nematodes,Heterorhabditisspp. andSteinernemaspp., among Host Insects at 9 and 20°C and Effects on Efficacy by Westerman, P.R.

“…The negative binomial distribution (NBD) with density-dependentkwas used to test and describe the distribution of nematodes inOtiorhynchus sulcatus, Galleria…”
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Penetration of the Entomopathogenic NematodeHeterorhabditisspp. into Host Insects at 9 and 20°C by Westerman, P.R

“…Biological control of black vine weevil,Otiorhynchus sulcatus, by means of the entomopathogenic nematode,Heterorhabditisspp., is difficult to obtain at low…”
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Relative importance of vertebrates and invertebrates in epigeaic weed seed predation in organic cereal fields by Westerman, P.R, Hofman, A, Vet, L.E.M, Werf, W., van der

“…Exclosure trials were conducted in four organic cereal fields in The Netherlands in 1999 and 2000 to determine the relative importance of vertebrates and…”
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Aggregation of entomopathogenic nematodes, Heterorhabditis spp. and Steinernema spp., among host insects at 9 and 20 degrees C and effects on efficacy by Westerman, P.R

“…The negative binomial distribution (NBD) with density-dependent k was used to test and described the distribution of nematodes in Otiorhynchus sulcatus,…”
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Penetration of the entomopathogenic nematode Heterorhabditis spp. into host insects at 9 and 20 degrees C by Westerman, P.R. (AB-DLO, Wageningen, The Netherlands.)

“…Biological control of black vine weevil, Otiorhynchus sulcatus, by means of the entomopathogenic nematode, Heterorhabditis spp., is difficult to obtain at low…”
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