Straw mulch increases potato yield and suppresses weeds in an organic production system

摘要

Late and early maturing potato cultivars were grown under two organic management systems using straw mulch or mechanical cultivation for weed management. It was found that application of straw mulch at emergence consistently increased total and marketable A-size yields for the late season cultivar Freedom Russet, and shifted the profile of marketable A-size tubers toward larger sizes. Increased yields were seen for the early season cultivar Dark Red Norland in some years, and may be related to amelioration of environmental stress by straw mulch. Mulch provided more effective control than mechanical cultivation for some broadleaf weeds, especially late in the season as potato foliage senesced and weed numbers tended to increase in unmulched plots relative to mulched plots. Grass weed incidence did not differ between straw mulched and mechanically weeded plots. Mulch did not consistently impact abundance of pest, virus vector, or predatory insects, although potato leafhopper numbers tended to be lower in straw mulched plots than mechanically cultivated plots. Straw mulching did not impact PVY incidence. It was concluded that straw mulching is a viable management option for organic potato production, with potential benefits for broadleaf weed management and tuber yield.