Uniformity trial size in estimates of plot size in restrict areas

Abstract

The aim of this study was to determine the uniformity trial size when estimating optimum plot size
in order to evaluate fresh phytomass in lettuce plants and fruit weight in sweet peppers. Production data, collected in
uniformity trial on lettuce in a plastic greenhouse in both summer and winter, lettuce in plastic tunnels in autumn and
winter, and sweet pepper in a plastic greenhouse in the summer-autumn and spring-summer seasons, were used to plan
different uniformity trial sizes in crop rows. In all the experiments, each plant was evaluated individually and considered
as a basic experimental unit. For each size in a uniformity trial, 3,000 resamples, randomly taken with replacement, were
used to estimate optimum plot size. Uniformity trial using 27 basic experimental units to evaluate the fresh phytomass
of lettuce plants, and with 29 basic experimental units to assess fruit weight in sweet pepper, are sufficient to estimate
optimum plot size, with an amplitude of the 95% confidence interval of less than or equal to two basic experimental
units.