Strip Tillage and Cover Crop Effects on Tomato and Pepper Crop Productivity

Standard vegetable production systems include raised beds topped with drip irrigation and plastic mulch is extremely popular; however, it also requires intense tillage, which degrades soil structure, contributes to runoff and erosion, and intensifies reliance on non-renewable resources. Reduced tillage systems, on the other hand, lack these negatives but also have been less productive than standard systems. The type, condition, and location of the cover crop or its residue strongly influence the performance of strip-till systems. Two paired studies were completed in 2015 at the OARDC in Wooster, Ohio specifically to document the productivity of pepper and tomato plants grown in plots representing different tillage and cover crop combinations. Each study (tomato, pepper) was a spilt-plot design with four replications, having system (raised bed and plastic mulch vs. flat strip-till) as the main factor and cover crop type (living mulch vs. dead mulch) as the sub-factor. The experimental area was sown to winter wheat in Fall-2014. In Spring-2015, regular plastic beds were shaped in experimental replicates after by moldboard plowing, herbicide and fertilizer application. Then, ryegrass seed was broadcast over the top and into the furrow of half of all raised-bed plots as living mulch; wind moved ryegrass seed to bed edges. For strip-till plots, wheat was mowed to promote tillering at regrowth. Two weeks later, wheat was killed with herbicide in the strip-till-dead mulch plots; while wheat was mowed a second time in strip-till-living mulch plots. Then, a PTO-driven roto-tiller with only one pair of tines was used to create 25-cm wide by 15-cm deep strips in the living and dead wheat plots. Tomato ‘Mountain Fresh’ and pepper ‘Aristotle’ were transplanted into the standard or strip-till plots in single rows. Plant growth and fruit yield were monitored in all plots. The tillage-cover interaction was not significant in either experiment (tomato, pepper). Tomato fruit yield and fruit number were similar between standard and strip-till plots but total and marketable fruit number and yield were greater in plots with dead compared to living mulch. Pepper values were more affected by system as marketable fruit number and yield values in strip-till plots tended to be 25% of those in standard plots. Also, for both crops, the harvest at which yield was greatest occurred later in strip-till than standard plots. Follow-up research will investigate additional factors that may influence the productivity of reduced tillage as systems as they apply to specific vegetable crops.