Size of uniformity trials for estimating the optimum plot size for vegetables

Abstract

The aim of this work was to determine the uniformity trial size for estimating the optimum plot size in order to evaluate the fruit mass of tomato, snap-beans and zucchini. The mass of fruits was evaluated in uniformity trials with tomato grown in plastic tunnel in spring-summer and autumn-winter seasons, with snap-beans in plastic greenhouse in autumn-winter season and, with zucchini in plastic greenhouse in summer-autumn and winter-spring seasons. These data were used for planning different sizes of uniformity trials and resampling with replacement was used to estimate the optimum plot size by the method of maximum curvature of the coefficient of variation model. The size of uniformity trials influences the estimation of the optimum plot size for evaluating the mass of fruits of tomato, snap-beans and zucchini. Uniformity trials with tomato with 12 basic experimental units (12 plants) and with snap-beans with 21 basic experimental units (42 plants) are enough for estimating the optimum plot size for evaluating the mass of fruits in plastic tunnel with a confidence interval of 95% minor or equal to two basic experimental units. Uniformity trials with snap-beans with 18 basic experimental units (36 plants) and with zucchini with ten basic experimental units (ten plants) in plastic greenhouse are enough for estimating the optimum plot size for evaluating the mass of fruits with a confidence interval of 95% minor or equal to three basic experimental units.

The Size of the Uniformity Trial Affects the Accuracy of Plot Size Estimation in Eggplant

“…An important point that should be emphasized in this work is that from a given simulation uniformity size, the AIC95% has a stabilizing of tendency, that is, as the size of the uniformity trial increases, the AIC95% varies very little with the size increase of the uniformity trial (Figures 1-4). The results found in this study are consistent with Cargnelutti Filho et al (2011), Schwertner et al (2015a), Schwertner et al (2015b), and Sari and Lucio (2018) who concluded that small uniformity trial provide plot size estimates with low accuracy.…”

“…The estimation of plot size is based on uniformity trials without treatments (Schwertner et al, 2015a;Schwertner et al, 2015b) and depends directly on the magnitude of the experimental variability (Lúcio & Benz, 2017). The variability of the data in multiple-harvests horticultural crops, such as Solanum melongena L., is related to several factors such as (i) heterogeneity of soil fertility; (ii) intensive management; (iii) uneven application irrigation and fertilizers; (iv) occurrence of pests, diseases, and weeds; (v) uneven maturity of fruits; (vi) presence or absence of suitable fruits to be harvested in a given harvest (Lúcio & Sari, 2017;Krysczun et al, 2018).…”

“…However, in these studies the authors did not have the concern to investigate the accuracy of the plot size estimates obtained in the uniformity trials. the other hand, studies that evaluated turnip forage (Cargnelutti Filho et al, 2011), tomato, green beans and Italian zucchini (Schwertner et al, 2015a) and lettuce and pepper (Schwertner et al, 2015b) pointed out that uniformity trials with a few number of basic experimental units (BEU) lead to inaccurate estimates of plot size, and it is important to elucidate the influence of uniformity trial size on plot size estimation.…”

Estimation of the Optimum Size of Plots for Soybean Radiometer Experiments

“…Experimental planning for the proper choice of plot size is an indispensable procedure for performing tests with experimental precision of acceptable magnitude (SCHWERTNER et al, 2015). When the experimental area is not a limiting factor, it is better to increase the number of repetitions than the plot size (LÚCIO and SARI, 2017).…”

Modelos de regresión segmentada para estimar el tamaño óptimo de la parcela experimental con caña de azúcar

“…Investigaciones actuales fueron en gran parte desarrollados en Brasil y aplicados en diversos cultivos, por ejemplo: crotalaria (Crotalaria juncea L.) (Facco et al, 2017), berenjena (Solanum melongena) (Krysczun et al, 2018), tomate cherry (Solanum lycopersicum L.) (Giacomini y Lúcio, 2018), tomate (Solanum lycopersicum), habichuelas (Phaseolus vulgaris) y calabacín (Cucurbita pepo) (Schwertner et al, 2015), girasol (Helianthus annus L.) (Santos et al, 2015), café (Coffea) (Mendes et al, 2016), taro (Colocasia esculenta) (Silva, 2014) y boniato (Ipomoea batatas) (Rodríguez et al, 2018).…”