Estratégias De Manejo Do Arranjo De Plantas Visando Otimizar a Produtividade De Grãos Do Milho

Abstract

RESUMO – Este trabalho foi conduzido objetivando avaliar a resposta do milho ao incremento na densidade deplantas, sob diferentes espaçamentos entre linhas. O experimento foi implantado em Lages-SC, nos dias 20/10/2014e 21/10/2015. Foram testadas cinco densidades de plantas (3, 5, 7, 9 e 11 pl m-2) e dois espaçamentos entre linhas(40 cm - reduzido, e 80 cm - convencional). Avaliaram-se características fenológicas, morfológicas, fisiológicas e aprodutividade em kg de grãos ha-1 do híbrido P30R50H. Os dados foram analisados estatisticamente pelo teste F, e asmédias foram comparadas pelo teste de Tukey e análise de regressão. A produtividade variou de 11.390 a 18.760 kg ha-1,dependendo do arranjo de plantas testado. Ele aumentou linearmente 923 e 724 kg ha-1 para cada planta adicionadapor m-2 no espaçamento entre linhas de 40 cm em 2014/2015 e 2015/2016, respectivamente. A elevação na densidadede plantas de 3 para 11 pl m-2 não promoveu assincronia floral, não reduziu a atividade fotossintética da folha índice,nem aumentou a percentagem de plantas acamadas, quando se utilizou o espaçamento entre linhas reduzido. Portanto,a utilização de densidades supraótimas (9 e 11 pl m-2) e espaçamento entre linhas reduzido (40 cm) foram estratégiasde manejo efetiva para otimizar a produtividade do milho.Palavras-chave: Zea mays, densidade, espaçamento entre linhas, rendimento. MANAGEMENT OF PLANT ARRANGEMENTTO OPTIMIZE GRAIN PRODUCTIVTY IN MAIZEABSTRACT – This work was set aiming to evaluate maize response to the increase in plant population at differentrow spacings. The experiment was conducted in Lages, SC, South of Brazil, on 10/20/2014 and 10/21/2015. Five plantdensities (3, 5, 7, 9 and 11 plants m-2) and two row spacings (40 cm – reduced; 80 cm – conventional) were tested.Phenological, morphological and physiological traits, productivity (kg of grains per ha-1) of the hybrid P30R50 wereevaluated. Data were assessed by the F test and means were compared by the Tukey’s test and regression analysis.Grain productivity ranged from 11,390 to 18,760 kg ha-1, depending on the plant arrangement. Linear increase of 923and 724 kg ha-1 was observed for each added plant per m-2 at the row spacing of 40 cm, in 2014/2015 and 2015/2016,respectively. The increase in plant density from 3 to 11 plants m-2 did not promote flower asynchrony, did not reducephotosynthetic activity of the index leaf, neither enhanced the percentage of lodged plants when the reduced rowspacing was used. Therefore, the use of supra-optimum plant densities (9 and 11 plants m-2) and reduced row spacing(40 cm) were efficient strategies of plant arrangement management to optimize maize grain productivity.Keywords: Zea mays, density, row space, productivity.

Influence of Seed Tube Curvature on Seed Longitudinal Distribution

“…The effects caused by the heterogeneity of longitudinal distribution of seeds are worse in crops that cannot compensate for this factor, such as corn (Sangoi et al, 2019) and sunflower (Pereira & Hall, 2019). The effect of an irregular deposition is little in crops that have phenotypic plasticity, such as soybean, but it still causes productivity losses (Beliavskaya, 2017;Büchling et al, 2017;Junior et al, 2018).…”

Spatial arrangements of corn grown in Brazilian savanna conditions

“…Several works in the literature report on the relationship between the spatial arrangement of plants and the corn yield (Torres et al, 2013;Kopper et al, 2017). However, the arrangement of plants in the crop can be altered by changes in population density, in the interrow spacing and, consequently, in the spatial distribution of plants in the row (Sangoi, Silva, & Argenta, 2010).…”

Leaf orientation of maize plants as influenced by seed positioning in the soil

“…This process depends mainly on effective interception of photosynthetically active radiation (PAR) (Loomis & Amthor, 1999). Management practices such as defining the arrangement of maize plants with different distribution and orientations of shapes and structures can contribute to improving its PAR interception efficiency (Argenta, Silva, & Sangoi, 2001;Petter et al, 2016), consequently increasing grain yield (Ottman & Welch, 1989;Kappes et al, 2010;Sangoi, Silva, & Argenta, 2010a).…”