207 Tillage Methods Affect the Growth of Sweetpotato

Abstract

<jats:p>Growth of the sweetpotato [<jats:italic>Ipomoea batatas</jats:italic> (L.) Lam.] is subject to environmental variation. High soil temperatures can restrict storage root initiation and development. Moreover, fluctuating soil moisture can have a pronounced effect on yield and quality. Cover crops, used in a conservation tillage system, could modify the soil environment. The objective of this research was to investigate the effects of conservation tillage on sweetpotato growth. A rye cover crop was broadcast seeded in Fall 1996, and sweetpotatoes were transplanted into the undisturbed residue the following spring. A fallow, unseeded plot represented the conventional method of sweetpotato culture. Plants were harvested at 14-day intervals commencing at 21 days after transplanting. Leaf area and dry weights of the storage roots and vines were recorded. Soil moisture was measured by taking soil cores at the depth of rooting (10 cm). The sweetpotatoes growing in the undisturbed rye residue had a significantly greater leaf area, vine weight, root set, and yield (particularly large grade class) relative to conventional-tilled sweetpotatoes. The rye residue was very effective in reducing soil evaporation.</jats:p>

Effects of a Killed-Cover Crop Mulching System on Sweetpotato Production, Soil Pests, and Insect Predators in South Carolina

“…This study and others (Bloodworth et al 1995, Jett 1999, Stone et al 2005, Treadwell 2005) indicate that killed-cover crop mulches can be used in sweetpotato production without causing increased insect damage or reduced yields. Overall, insect injury ratings for sweetpotatoes grown under killed-cover cropping mulch in this study were not greatly different from those grown in the conventional tillage system with the same weed control.…”

“…A simple adaptation to a conventional planter was used in the transplantation of sweetpotato slips into heavy residue plots (Edwards et al 1998). Jett (1999) reported that sweetpotatoes grown in an undisturbed rye residue in Louisiana had a signiÞcantly greater leaf area, vine weight, root set, and yield relative to conventionally tilled sweetpotatoes, which was attributed to lower soil temperatures that increased root set. However, in one experiment, white grubs, Phyllophaga ephilida Say, were higher in the conservation tillage plots (Jett and Talbert 1997).…”

Nutrient Management with Cover Crops and Compost Affects Development and Yield in Organically Managed Sweetpotato Systems

“…In a Louisiana study of cover crop use in a conventional sweetpotato 'Beauregard' system, Jett and Talbot (1998) found that when incorporated, rye and ryegrass reduced soil erosion and increased yields of sweetpotato. In a subsequent study, sweetpotatoes growing in undisturbed rye residue had higher leaf area, vine weight, root set, and yield relative to conventional tilled sweetpotatoes (Jett, 1999). The researchers hypothesized that the cover crop residue favorably modified the soil environment by eliminating early restriction to root set often caused by high soil temperatures (Jett, 1999).…”

Cover Crop Management Affects Weeds and Yield in Organically Managed Sweetpotato Systems

“…When cover crop residues remain on the surface, weed seed germination can be inhibited because of a change in the soil microenvironment (Teasdale and Mohler 1993) as well as physical interference by the residue (Creamer et al 1996;Hutchinson and McGiffen 2000;Mohler and Teasdale, 1993). To this end, reduced tillage vegetable production has been hypothesized as an alternate system to reduce weed occurrence as well as improve soil properties (Hoyt 1999;Jett 1999).…”