Plant Spatial Arrangement and Density Effects on Small- and Medium-vined Processing Tomatoes

Abstract

Abstract ‘Heinz 2653’ and ‘Heinz 722’ tomatoes (Lycopersicon esculentum Mill.) were grown at four plant populations (21,530, 28,700, 43,050, and 57,400 plants/ha) in both single and twin rows. Plant density had no influence on ripe fruit yields of ‘H-2653’. The twin-row configuration did result in increased yields from ‘H-2653’, but not ‘H-722’. Density had no influence on yield of ‘H-722’ in 1984, but yield was reduced at the highest density of the twin-row configuration in 1983. Shoot dry matter, ripe fruit yields, and total yields per hectare of ‘H-2653’ were higher from the twin rows than from the single rows. There were no yield advantages for ‘H-722’ in twin-row arrangements. The ‘H-2653’ yield increases in twin rows were due to an increase in number of ripe fruit per plant. As population pressures increased, the number of ripe fruit per plant, ripe fruit size, and clusters per plant decreased. Plants grown in twin rows covered a greater percentage of their allotted space than those in single rows, regardless of cultivar. As the population density increased, the canopy coverage also increased. Plants at high densities and those in twin-row arrangements intercepted more light than those at low density and single-row plantings.