Seasonal patterns in post-dispersal seed predation of Abutilon theophrasti and Setaria faberi in three cropping systems

Summary 1 Post-dispersal seed predation is an important source of mortality for arable weed populations that can potentially contribute to ecologically based management strategies. The extent to which cropping practices influence rates of seed predation is not well established. 2 Removal of Abutilon theophrasti and Setaria faberi seeds by predators was measured in 2-year (maize/soyabean), 3-year (maize/soyabean/triticale + red clover) and 4-year (maize/soyabean/triticale + lucerne/lucerne) crop rotations in Iowa, USA, during 27 48-h sampling periods conducted during the 2003 and 2004 cropping seasons. 3 Predation of S. faberi seeds was equal (eight sampling periods) or greater (19 sampling periods) than predation of A. theophrasti seeds, but the influence of crops on seasonal predation patterns was generally similar for the two weeds. 4 Seasonal patterns in seed predation were crop-specific and complementary. In maize and soyabean, seed predation was low in spring, high in summer and low in autumn. In triticale–legume intercrops, seed predation was high in spring, low in summer and moderate in autumn. In lucerne, seed predation fluctuated from high to low, matching the periodic harvest and regrowth cycle of the crop. 5 Measurements of crop canopy light interception taken in 2004 were positively correlated with rates of seed removal for both A. theophrasti (r = 0·54, P < 0·001) and S. faberi (r = 0·25, P < 0·001), suggesting that vegetative cover promotes weed seed predation. 6 Synthesis and applications. The results indicate that crop vegetation can be managed to promote weed seed predation. Diversified farming systems that include a range of phenologically dissimilar crop species are likely to provide the greatest opportunities for weed seed destruction by predators.

[1]  James H. Brown,et al.  Granivory in Desert Ecosystems , 1979 .

[2]  E. Redente,et al.  Effects of Selective Seed Predation by Rodents on Shortgrass Establishment , 1995 .

[3]  M. Liebman,et al.  Demography of Abutilon theoprasti and Setaria faberi in three crop rotation systems , 2006 .

[4]  Mario Díaz,et al.  Spatial and temporal patterns of granivorous ant seed predation in patchy cereal crop areas of central Spain , 1992, Oecologia.

[5]  R. Reader Control of seedling emergence by ground cover: a potential mechanism involving seed predation. , 1991 .

[6]  Gerald E. Brust,et al.  Weed seed destruction by arthropods and rodents in low-input soybean agroecosystems , 1988 .

[7]  R. Bommarco REPRODUCTION AND ENERGY RESERVES OF A PREDATORY CARABID BEETLE RELATIVE TO AGROECOSYSTEM COMPLEXITY , 1998 .

[8]  R. Alexander The Taxonomy of the Field Crickets of the Eastern United States (Orthoptera: Gryllidae: Acheta) , 1957 .

[9]  R. W. Pearcy Radiation and light measurements , 2000 .

[10]  Matt Liebman,et al.  Cropping system effects on giant foxtail (Setaria faberi) demography: I. Green manure and tillage timing , 2003, Weed Science.

[11]  R. Manson,et al.  Links between microhabitat preferences and seed predation by small mammals in old fields , 1998 .

[12]  S. B. Wall,et al.  SEED REMOVAL, SEED PREDATION, AND SECONDARY DISPERSAL , 2005 .

[13]  W. van der Werf,et al.  Annual losses of weed seeds due to predation in organic cereal fields , 2003 .

[14]  M. Brewer,et al.  Small mammal populations occurring in a diversified winter wheat cropping system , 2003 .

[15]  Philip M. Dixon,et al.  Are many little hammers effective? Velvetleaf (Abutilon theophrasti) population dynamics in two- and four-year crop rotation systems , 2005, Weed Science.

[16]  D. Landis,et al.  Influence of Refuge Habitats and Cover Crops on Seasonal Activity-Density of Ground Beetles (Coleoptera: Carabidae) in Field Crops , 1999 .

[17]  R. J. Holmes,et al.  Post-dispersal weed seed predation by avian and non-avian predators , 2005 .

[18]  Vojtech Jarosik,et al.  Ground beetles (Carabidae) as seed predators , 2003 .

[19]  R. B. Root Organization of a Plant-Arthropod Association in Simple and Diverse Habitats: The Fauna of Collards (Brassica Oleracea) , 1973 .

[20]  H. Thiele Carabid Beetles in Their Environments: A Study on Habitat Selection by Adaptations in Physiology and Behaviour , 1977 .

[21]  F. James Rohlf,et al.  Biometry: The Principles and Practice of Statistics in Biological Research , 1969 .

[22]  D. Landis,et al.  Herbaceous Filter Strips in Agroecosystems: Implications for Ground Beetle (Coleoptera: Carabidae) Conservation and Invertebrate Weed Seed Predation , 2001, The Great Lakes Entomologist.

[23]  E. Regnier,et al.  Postdispersal predation of giant ragweed (Ambrosia trifida) seed in no-tillage corn , 2003, Weed Science.

[24]  L. Getz,et al.  Potential effects of small mammals in high-intensity agricultural systems in east-central Illinois, U.S.A. , 1986 .

[25]  B. Kromp Carabid Beetle Communities (Carabidae, Coleoptera) in Biologically and Conventionally Farmed Agroecosystems , 1989 .

[26]  David A. Mortensen,et al.  Simulation analysis of crop rotation effects on weed seedbanks. , 1995 .

[27]  Katherine L. Gross,et al.  Weed seed loss due to predation in Michigan maize fields , 1997 .

[28]  R. Kremer,et al.  Examination of Microorganisms and Deterioration Resistance Mechanisms Associated with Velvetleaf Seed1 , 1984 .

[29]  D. Wanner,et al.  Ground beetle abundance in organic and conventional corn fields. , 1980 .

[30]  S. Thompson Microhabitat Utilization and Foraging Behavior of Bipedal and Quadrupedal Hetermoyid Rodents , 1982 .

[31]  Benjamin R. Stinner,et al.  Postdispersal Predation of Velvetleaf (Abutilon theophrasti) Seeds , 1996, Weed Science.

[32]  S. Wratten,et al.  Creation of island' habitats in farmland to manipulate populations of beneficial arthropods : predator densities and species composition , 1991 .

[33]  P. Dixon,et al.  USING MATRIX MODELS TO DETERMINE CROPPING SYSTEM EFFECTS ON ANNUAL WEED DEMOGRAPHY , 2004 .

[34]  Douglas A. Landis,et al.  Refuge habitats modify impact of insecticide disturbance on carabid beetle communities , 2001 .

[35]  K. Gross,et al.  Experimental studies of seed predation in old-fields , 1984, Oecologia.

[36]  Douglas A. Landis,et al.  Post-dispersal weed seed predation in Michigan crop fields as a function of agricultural landscape structure. , 2000 .

[37]  W. S. Abbott,et al.  A method of computing the effectiveness of an insecticide. 1925. , 1925, Journal of the American Mosquito Control Association.

[38]  H. Smith,et al.  Predation of annual grass weed seeds in arable field margins , 1993 .

[39]  S. J. Watson,et al.  Post‐dispersal seed predation of non‐target weeds in arable crops , 2005 .

[40]  William E. Grant,et al.  IMPORTANCE OF VEGETATIVE COVER TO CYCLES OF MICROTUS POPULATIONS , 1976 .

[41]  Clarence J. Swanton,et al.  Influence of tillage and crop residue on postdispersal predation of weed seeds , 1999, Weed Science.

[42]  P. Hulme Post-dispersal seed predation in grassland: its magnitude and sources of variation. , 1994 .

[43]  R. D. Alexander,et al.  Systematic and Behavioral Studies on the Crickets of the Nemobius Fasciatus Group (Orthoptera: Gryllidae: Nemobiinae)1 , 1959 .

[44]  Francis A. Drummond,et al.  Effect of cover-cropping systems on invertebrate seed predation , 2005, Weed Science.

[45]  D. Letourneau,et al.  Vegetation management and biological control in agroecosystems , 1982 .