Plant Density and Inter-row Polyethylene Mulch Treatment Affect Growth and Yield of Tomato

Abstract

A field study was conducted to compare the effect of different planting densities and polyethylene mulch treatments on growth and yield of `Mountain Fresh' trellised tomato grown on raised beds on 1.8-m centers. The experiment design was a split plot with four replications and four mulch treatments as main effects: 1) standard black mulch (B), 2) Sonoco red mulch (R), 3) black mulch with interrow (between beds) reflective white on black mulch (B/W), and 4) red mulch with inter-row R/W. Subtreatments were three within-row spacings: 1) 0.60 m (8966 plants/ha); 2) 0.45 m (11955 plants/ha; standard spacing), and 3) 0.30 m (17932 plants/ha). Yield was determined from eight-plant plots and adjacent plants were harvested at regular intervals to determine plant biomass accumulation and partitioning of biomass among roots, stems, leaves, and reproductive organs. There was a linear increase in yield among mulch treatments with increasing plant density. The B/W mulch treatment increased midseason and total yields ≈20% over that of the other mulch treatments. Fruit yield of plants with the B/W mulch treatment at the 0.3-m spacing was 54% higher (151 MT/ha) than that of plants grown on black mulch with the standard plant spacing of 0.45 m (97.9 MT/ha). There was a linear decrease in fruit size with increasing plant density; however, plants grown at the 0.30-m spacing on the B/W mulched plots exhibited only a 2.7% decrease in fruit size as compared to plants grown at the standard 0.45-m spacing on black mulch.