Tamanho Ótimo De Parcela Para a Cultura De Girassol Em Três Arranjos Espaciais De Plantas

Abstract

RESUMO -O objetivo deste estudo foi avaliar o tamanho ótimo de parcela de três híbridos de girassol em três arranjos espaciais de plantas. O teste de uniformidade foi instalado no campo experimental da Universidade Federal do Recôncavo da Bahia, em Cruz das Almas, Brasil, em 2012. As parcelas foram compostas por seis linhas de 36 m, sendo dispostos três arranjos espaciais de plantas, quais sejam: A1 (0,45 mx 0,49 m); A2 (0,70 mx 0,32 m); e A3 (0,90 mx 0,25 m). Foram distribuidos em cada arranjo três híbridos de girassol: Hélio 250; Hélio 253; e Aguara 3. Para a avaliação do tamanho ótimo de parcela , aos 110 dias após a semeadura, foi colhida uma amostra de 180 unidades básicas (plantas) por parcela, no qual foram avaliadas a altura final de planta, o diâmetro final da haste e o diâmetro do capítulo. Foram simulados 31 tamanhos de parcela dos três híbridos e para cada variável analisada em cada planta considerada como uma unidade básica. A estimativa do tamanho de parcela para a cultura de girassol foi calculada pelo método de máxima curvatura modificada. O uso combinado do híbrido H253, instalado no arranjo de 0,45 mx 0,49 m, promoveu a obtenção do maior valor da máxima curvatura, estimando-se o tamanho ótimo de parcela de seis plantas. Palavras OPTIMAL SIZE OF PLOTS FOR THE CULTURE OF SUNFLOWER CROP IN THREE SPATIAL ARRANGEMENTS OF PLANTSABSTRACT -The objective of this study was to evaluate the optimum plot size to three sunflower hybrids in three spatial arrangements of plants. The uniformity test was installed in the experimental field of the Federal University of Recôncavo of Bahia, in Cruz das Almas, Brazil, in 2012. The plots were composed of six lines of 36 m, which were willing three spatial arrangements of plants: A1 (0,45 m x 0,49 m); A2 (0,70 m x 0,32 m) and A3 (0,90 m x 0,25 m), and each arrangement were distributed three sunflower hybrids: Hélio 250, Hélio 253 e Aguara 3. For the evaluation of the optimal plot size, at 110 days after sowing was harvested a sample of 180 basic units (plants) per plot, in which were evaluated the final plant height, the final diameter of the rod and the diameter of the chapter. Thirty-one plots sizes of three hybrids were simulated and for each variable assessed, wherein each plant was considered as a basic unit. The estimation of optimum plot size to the sunflower crop was calculated by the method of modified curvature maximum. The combined use of hybrid H253, installed in the arrangement 0.45 m x 0.49 m, promotes obtainment the greatest value of curvature maximum it was estimated the optimum plot size of six plants.

Size of plots for experiments with cactus pear cv. Gigante

“…These estimates express adequate precision in the fitting of the models. Santos et al (2015) simulated plot sizes for different hybrids of sunflower using modified maximum curvature method (MMCM) and obtained similar fits to those of the present study, with R² between 0.8806 and 0.9648 for the optimal plot sizes. With this same estimator, R², Cargnelutti Filho et al (2018) identified the optimal plot size (XMC, in m²), with fit of 0.9989 to evaluate the fresh mass of forage turnip.…”

“…Optimal plot sizes varied according to the evaluated characteristics, with XMC and X estimates between 2.14 and 7.72 and three and eight BEUs, respectively (Figure 1). The MMCM, besides estimating the optimal plot size preestablished by the critical point, also presents intermediate sizes among those tested, as observed in several studies (Cargnelutti Filho et al, 2014;Santos et al, 2015;Guarçoni et al, 2017).…”

“…The relation between plot size (BEU) and ECV (Table 2) can be explained by an exponential regression equation, ECV = 49.028x -0.468 ; R² = 0.9557. Nonlinear reduction of ECV is commonly associated with BEU size both in width and length, and such inverse relation between the statistical parameters has been corroborated by several studies (Santos et al, 2015;Brum et al, 2016;Sousa et al, 2016;Cargnelutti Filho et al, 2018). Figure 1 represents the relation between ECV and plot size in BEU.…”

“…However, when optimal plot size is achieved the continuous reduction of ECV leads to no gains in experimental precision because, from the critical or maximum curvature point, ECV tends to stability (Santos et al, 2015).…”

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).…”