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Weed Ecology and Nonchemical Management under Strip-Tillage: Implications for Northern U.S. Vegetable Cropping Systems

Published online by Cambridge University Press:  20 January 2017

Daniel C. Brainard ,
R. Edward Peachey ,
Erin R. Haramoto ,
John M. Luna  and
Anusuya Rangarajan
Daniel C. Brainard*
Affiliation:
Department of Horticulture, Michigan State University, A440 A Plant and Soil Sciences Building, 1055 Bogue Street, East Lansing, MI 48824
R. Edward Peachey
Affiliation:
Department of Horticulture, Oregon State University, 4017 Agriculture and Life Sciences Building, Corvallis, OR 97331
Erin R. Haramoto
Affiliation:
Department of Horticulture, Michigan State University, A440 A Plant and Soil Sciences Building, 1055 Bogue Street, East Lansing, MI 48824
John M. Luna
Affiliation:
Department of Horticulture, Oregon State University, 4017 Agriculture and Life Sciences Building, Corvallis, OR 97331
Anusuya Rangarajan
Affiliation:
Department of Horticulture, Cornell University, 121 Plant Sciences Building, Ithaca, NY 14853
*
Corresponding author's E-mail: brainar9@msu.edu
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Abstract

In northern U.S. vegetable cropping systems, attempts at no-till (NT) production have generally failed because of poor crop establishment and delayed crop maturity. Strip tillage (ST) minimizes these problems by targeting tillage to the zone where crops are planted while maintaining untilled zones between crop rows, which foster improvements in soil quality. ST has been shown to maintain crop yields while reducing energy use and protecting soils in vegetable crops, including sweet corn, winter squash, snap bean, carrot, and cole crops. Despite potential benefits of ST, weed management remains an important obstacle to widespread adoption. Increased adoption of ST in cropping systems for which effective, low-cost herbicides are either limited (e.g., most vegetable crops) or prohibited (e.g., organic systems) will require integration of multiple cultural, biological, and mechanical approaches targeting weak points in weed life cycles. Weed population dynamics under ST are more complex than under either full-width, conventional tillage (CT) or NT because weed propagules—as well as factors influencing them—can move readily between zones. For example, the untilled zone in ST may provide a refuge for seed predators or a source of slowly mineralized nitrogen, which affects weed seed mortality and germination in the tilled zone. Greater understanding of such interzonal interactions may suggest manipulations to selectively suppress weeds while promoting crop growth in ST systems. Previous studies and recent experiences in ST vegetable cropping systems suggest a need to develop weed management strategies that target distinct zones while balancing crop and soil management tradeoffs. For example, in untilled zones, optimal management may consist of weed-suppressive cover crop mulching, combined with nitrogen exclusion and high-residue cultivation as needed. In contrast, weed management in the tilled zone may benefit from innovations in precision cultivation and flame-weeding technologies. These short-term strategies will benefit from longer-term approaches, including tillage-rotation, crop rotation, and cover cropping strategies, aimed at preventing seed production, promoting seed predation and decay, and preventing buildup of problematic perennial weeds. However, a concerted research effort focused on understanding weed populations as well as testing and refining integrated weed management strategies will be necessary before ST is likely to be widely adopted in vegetable cropping systems without increased reliance on herbicides.

En los sistemas de cultivos de vegetales del norte de Estados Unidos, los intentos de producción con cero labranza (NT) generalmente han fallado debido a un establecimiento pobre y madurez tardía del cultivo. El cultivo en bandas (ST) minimiza estos problemas al enfocar la labranza en la zona donde los cultivos son plantados mientras que mantiene zonas sin labrar entre las líneas del cultivo, lo cual mejora la calidad del suelo. ST ha mostrado la capacidad de mantener el rendimiento del cultivo al tiempo que reduce el uso de energía y protege el suelo en cultivos de vegetales, incluyendo maíz dulce, calabacín de invierno, frijol común, zanahoria y coles. A pesar de los beneficios potenciales de ST, el manejo de malezas continúa siendo un obstáculo importante para su mayor adopción. El incremento en la adopción de ST en sistemas de cultivos para los cuales herbicidas efectivos y de bajo costo son, ya sea, limitados (e.g., mayoría de cultivos de vegetales) o prohibidos (e.g., sistemas orgánicos), requerirá la integración de múltiples estrategias culturales, biológicas, y mecánicas dirigidas a los puntos débiles en los ciclos de vida de las malezas. Las dinámicas de poblaciones de las malezas en ST son más complejas que en labranza de cobertura total, labranza convencional (CT) o NT, porque los propágulos de las malezas, además de los factores que los influencian, pueden moverse ampliamente entre zonas. Por ejemplo, la zona no labrada en ST podría proveer refugio para depredadores de semillas o podría ser una fuente de nitrógeno de lenta mineralización, los cuales afectan la mortalidad y la germinación de las semillas de las malezas en la zona labrada. Un mayor entendimiento de tales interacciones entre zonas podría sugerir manipulaciones para suprimir las malezas selectivamente mientras se promueve el crecimiento del cultivo en sistemas ST. Estudios previos y experiencias recientes en sistemas de cultivos de vegetales en ST indican la necesidad de desarrollar estrategias de manejo de malezas que apuntan a zonas específicas mientras balancean los conflictos entre el manejo del cultivo y del suelo. Por ejemplo, en zonas sin labrar, el manejo óptimo podría consistir en usar cultivos de cobertura para la supresión de malezas, en combinación con la exclusión de nitrógeno y el uso del cultivo con altos residuos cuando sea necesario. En contraste, el manejo de malezas en la zona labrada podría beneficiarse de innovaciones en tecnología de cultivadores de precisión y de quemadores de llama. Estas estrategias de corto plazo se beneficiarán de estrategias de largo plazo orientadas a prevenir la producción de semillas, promover la depredación y degradación de semillas, y a prevenir el incremento de malezas perennes problemáticas. Sin embargo, un esfuerzo concertado de investigación enfocado no solo en entender las poblaciones de malezas, sino que en evaluar y refinar las estrategias integradas de malezas, será necesario antes de que ST sea ampliamente adoptada en sistemas de cultivos de vegetales sin una dependencia mayor en herbicidas.

Keywords

Carrot, Daucus carota L.cole crops, Brassica sppsnap bean, Phaseolus vulgaris L.sweet corn, Zea mays L.winter squash, Cucurbita moschata Duchesne ex PoirTillagevegetable cropsweed control
Type
Symposium
Information
Weed Technology , Volume 27 , Issue 1 , March 2013 , pp. 218 - 230
Copyright
Copyright © Weed Science Society of America 

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