Weed Control with Cover Crops in Irrigated Potatoes

J.E Stenger,G.H Mehring,H.M Hatterman-Valenti

doi:10.3390/agronomy6010003

Abstract

Field experiments at Oakes, ND, USA in 2010 and Carrington, ND, USA in 2011 were conducted to evaluate the potential for cover crops grown in the Northern Great Plains, USA in order to reduce weed emergence and density in irrigated potatoes. Treatments included five cover crop treatments and three cover crop termination treatments. Termination of cover crops was done with glyphosate, disk-till, and roto-till. Cover crop biomass accumulation was greatest for rye/canola and triticale at Oakes, and hairy vetch and hairy vetch/rye at Carrington. Cover crop and termination affected weed control 14, 29, and 51 days after planting (DAP) at Oakes. Weed control at Carrington was at least 90% for all cover crop and termination treatments at all three evaluation timings. Marketable yield at Oakes was greater when roto-till was used to terminate the cover crops compared with disk-till or herbicide, which is beneficial for organic systems where herbicides are not used. Marketable yield at Carrington was not affected by cover crop or termination treatments. Results suggest that cover crops can successfully be integrated into irrigated potato production for weed control with yields equal to no cover crop, and with attention to potential mechanical difficulties.

Highlights

Potato (Solanum tuberosum L.) production in conventional agriculture is an intensive process from seed bed preparation to pest control, while ensuring high yields through fertility and hill management [1]
Winter annual cover crops are primarily grown in the Northern Great Plains during the late summer and fall months, planted from the middle of August onwards
Cover crop biomass accumulation was greater for rye/canola and triticale compared with the turnip/radish cover crop at Oakes in 2010 (Table 1)

Summary

Introduction

Potato (Solanum tuberosum L.) production in conventional agriculture is an intensive process from seed bed preparation to pest control, while ensuring high yields through fertility and hill management [1]. Winter annual cover crops are primarily grown in the Northern Great Plains during the late summer and fall months, planted from the middle of August onwards. This timing does not preclude growing a cash crop but often limits the production of crops with longer growing seasons [4,5]. Rye (Secale cereale L.) and triticale (Triticum durum L.) are winter hardy when used as cover crops planted in the fall, with extensive root systems and quick accumulation of biomass [6]. Hairy vetch (Vicia villosa Roth) is a nitrogen-fixing legume that vines extensively and provides excellent soil cover [6]. Turnip and radish can decrease soil compaction and increase nutrient capture [7,8]

Objectives

Results

Conclusion