Monitoring corn and soybean agroecosystems after establishing no-tillage practices in Québec, Canada

Abstract

, H. 2007. Monitoring corn and soybean agroecosystems after establishing no-tillage practices in Québec, Canada. Can. J. Plant Sci. 87: 841-849. The conversion to no-tillage (NT) may seem risky to some producers who rely on tillage to control weeds, some insect pests and disease-causing pathogens that can reduce crop yield. Weeds, arthropods, and disease incidence were monitored in silage corn (Zea mays L.) and soybean (Glycine max L. Merr.) agroecosystems with CT and newly established NT plots in Ste-Anne-de-Bellevue, Québec. During the first 2 establishment years, there were more annual grass and fewer annual broadleaf weeds in NT than in CT plots, but the surface area covered by weeds (broadleaf, grasses and perennials) was greater in CT than NT plots. Foliar arthropods were more numerous in soybean than corn plots in both years, but were unaffected by tillage. There were more ground-dwelling generalist predators, especially Coleoptera and Carabidae, in CT than NT plots, while spiders and harvestmen (Araneae and Opiliones) were dominant in NT plots. Crop damage from insect pests and diseases was below economic thresholds, but 5 yr of yield monitoring (2000)(2001)(2002)(2003)(2004) revealed a trend of greater silage corn and soybean yields in CT than NT plots. The reduction in crop yield after establishing NT practices at this site was probably due to rooting constraints from inadequate seedbed preparation in the NT system, rather than from weed competition, insect damage or crop diseases.Key words: Arthropods, crop disease, silage corn, soybean, tillage, weed control Whalen, J. K., Prasher, S. O. et Benslim, H. 2007. Surveillance aux agro-écosystèmes de maïs-ensilage et de soya convertis en semis-direct au Québec, Canada. Can. J. Plant Sci. 87: 841-849. Le système de semis-direct (NT) peut sembler risqué pour quelques producteurs qui comptent sur le labourage pour contrôler les mauvaises herbes, quelques insectes ravageurs et les pathogènes causant des maladies qui peuvent réduire la production végétale. Nous avons examiné des mauvaises herbes, des arthropodes, et l'incidence des maladies dans les agro-écosystèmes de maïs-ensilage (Zea mays L.) et soya (Glycine max L. Merr.), aux parcelles nouvellement converties en NT à Sainte-Anne-de-Bellevue, Québec. Pendant les deux premières années d'étab-lissement, il y avait plus des mauvaises herbes annuelles et moins des dicotylédones annuelles avec NT que dans les parcelles avec CT, mais le degré d'envahissement par les mauvaises herbes était plus grand dans le CT que le NT. Pendant deux ans, les arthropodes foliaires étaient plus nombreux en soya par apport au maïs-ensilage, mais ils n'étaient pas affectés par le labourage du sol. Il y avait plus de prédateurs de généraliste, particulièrement les coléoptères et les Carabidae, dans le CT que le NT, alors que les araignées et les faucheux (Araneae et Opiliones) étaient dominants dans les parcelles sous NT. La diminution du rendement de la récolte après l'établissement du NT sur ce site a été probablement due à la dif...

Growth of Corn Roots and Associated Arbuscular Mycorrhizae Are Affected by Long‐Term Tillage and Phosphorus Fertilization

“…In NT treatments, the greater P concentration in corn shoot indicates that P is not limiting corn growth, but something else is limiting. Under cool and humid climates as encountered in Quebec, enhancing soil drying and warming in spring are major advantages associated with MP (Whalen et al, 2007) that have contributed to better corn productivity in MP than NT systems. In addition, weeds and high surface residue cover favoring the proliferation of insect pests and pathogens could negatively impact corn growth in the NT plots (Burgess et al, 1996; Mehdi et al, 1999; Whalen et al, 2007).…”

“…Under cool and humid climates as encountered in Quebec, enhancing soil drying and warming in spring are major advantages associated with MP (Whalen et al, 2007) that have contributed to better corn productivity in MP than NT systems. In addition, weeds and high surface residue cover favoring the proliferation of insect pests and pathogens could negatively impact corn growth in the NT plots (Burgess et al, 1996; Mehdi et al, 1999; Whalen et al, 2007). Thus, under NT, the beneficial effects of the greater corn P concentration on shoot biomass production seem to be compromised by other limitations controlling the growth of plants, particularly under cool and humid climates.…”

Tillage and crop rotation effects on the yield of corn, soybean and wheat in eastern Canada

“…In the same test they determined that there was no significant influence of tillage practice on soybean yield with NT yielding 6% more than CT on average, and that following five years of continuous corn, soybean yield increased by 8% over continuous soybean. In a five year study of a silage corn soybean rotation in Quebec, Whalen et al (2007) found that CT silage corn was significantly higher yielding than NT silage corn in three of five years and had similar yields in the other two years. They also determined that CT soybean had greater yield than NT soybean in two of five years and similar yield in three of five years and proposed that corn yields were reduced under NT due to root constraints rather than weed competition or insect or disease damage.…”

The effects of conventional and organic cropping systems on food and reproductive success of Song Sparrows in eastern Ontario farmland

“…Tillage typically decreases the abundance or activity density of soil macro arthropods such as ground beetles and spiders (Araneae, House and Parlee, 1985, Stinner and House, 1990, Holland and Reynolds, 2003, Thorbek and Bilde, 2004 Baraibar et al, 2009, Errouissi et al, 2011. However, some studies show either no effect of tillage (Carcamo et al, 1995, Baguette and Hance, 1997, Huusel-Veistola, 1998, or a positive effect of tillage (Carcamo 1995, Whalen et al, 2007, and results often vary by taxon (Tonhasca, 1993, Baguette and Hance, 1997, Shearin et al, 2007, Thorbeck and Bilde, 2004. Results for pests and invertebrates living in foliage are even more variable (Stinner et al, 1988, Stinner and House, 1990, Tonhasca, 1993, Costamagn and Landis, 2006, Whalen et al, 2007, Hatten et al, 2010.…”

“…However, some studies show either no effect of tillage (Carcamo et al, 1995, Baguette and Hance, 1997, Huusel-Veistola, 1998, or a positive effect of tillage (Carcamo 1995, Whalen et al, 2007, and results often vary by taxon (Tonhasca, 1993, Baguette and Hance, 1997, Shearin et al, 2007, Thorbeck and Bilde, 2004. Results for pests and invertebrates living in foliage are even more variable (Stinner et al, 1988, Stinner and House, 1990, Tonhasca, 1993, Costamagn and Landis, 2006, Whalen et al, 2007, Hatten et al, 2010. The negative effect of increased tillage on at least some invertebrate taxa might explain some of the variability in invertebrate response to organic field management.…”