Fontes e doses de molibdênio via foliar em duas cultivares de feijoeiro

Abstract

RESUMO Visando a estudar a resposta de duas cultivares de feijoeiro (Phaseolus vulgaris L.) a fontes e doses de molibdênio via foliar, foram conduzidos três ensaios em um Latossolo Vermelho distroférrico típico (seca e inverno-primavera 97) e um Podzólico MOLYBDENUM SOURCES AND RATES APPLIED ON LEAVES OF TWO COMMON BEAN CULTIVARSABSTRACT Three field experiments were conducted in southern Minas Gerais State, on distrofic Dusky Red Latosol (1997 summer/fall and winter/spring growing seasons) and on a Red Yellow Podzolic (1997/98 summer season), to study the response of two common bean cultivars (Phaseolus vulgaris L.) to molybdenum (Mo) sources and rates of application on leaves. The experimental design was randomized blocks with three replications and a 2x2x4 factorial arrangement, involving two bean cultivars (Carioca and Carioca-MG), two Mo sources (sodium and ammonium molybdates) and four Mo rates (0, 50, 100, and 150g ha -1 Mo), applied on leaves at 21-25 days after emergency . At harvest, the grain yield and their primary components (number of pod per plant, number of grains per pod and weight of one hundred seeds), and the final stand, were evaluated. Results showed no effect of the molybdenum sources on grain yield and yield components. In both cultivars, grain yield increased with increasing Mo rates up to 54 g ha -1 of Mo, following a discontinuous linear response, or LPR (Linear Response-Plateau). INDEX TERMS: Foliar fertilization, molybdenum fertilization, Phaseolus vulgaris. INTRODUÇÃOEntre os micronutrientes essenciais, o molibdê-nio (Mo) tem despertado grande interesse entre pesquisadores e produtores envolvidos com a cultura do feijoeiro, principalmente por causa dos resultados espetaculares que vêm sendo obtidos com a adubação molíbdica foliar (Vieira, 1994 a; Rodrigues et al., 1996).A aplicação foliar de molibdênio eleva os teores de nitrogênio nas folhas dos feijoeiros, que se tornam 1. Parte de projeto financiado pela FAPEMIG. 2. Engenheiro Agrônomo, mestrando, bolsista do CNPq.

Molybdenum mixed with glyphosate and alone via foliar spray in no-tillage common bean grown on corn stover

“…Fernandes et al (2005) evaluated the application of foliar Mo and N, in-furrow or sidedress, to no-tillage bean on corn stover and also found no difference for PNP. However, reports of increased PNP in response to Mo application are common in the literature (Pessoa et al, 2001;Silva et al, 2003a;Nascimento et al, 2009). For the year effect, the average PNP was higher in 2010 (Table 3).…”

Aplicação foliar simultânea de molibdênio e alguns defensivos agrícolas na cultura do feijoeiro

“…Especial atenção tem sido direcionada aos micronutrientes, principalmente ao molibdênio, cuja aplicação, principalmente via foliar, intensifica a coloração verde e a concentração de N das folhas e eleva o número de vagens por planta e o tamanho dos grãos, resultando em significativo incremento de rendimento (AMANE et al, 1994;BERGER et al, 1996;RODRIGUES et al, 1996;ANDRADE et al, 1998;DINIZ et al, 1998;LIMA et al, 1999;ANDRADE et al, 2001). Esse efeito, conforme comprovou Vieira (1994) em experimentos de campo, está relacionado à influência desse micronutriente na atividade das enzimas nitrogenase e redutase do nitrato.…”

“…Não se tem constatado resposta diferencial de cultivares de feijoeiro ao Mo aplicado via foliar (RODRIGUES et al, 1996), cuja dose ótima tem se situado entre 80 e 90 g ha -1 de Mo (BERGER et al, 1996;RODRIGUES et al, 1996). Para esse mesmo tipo de aplicação, foi constatado ainda que tanto o molibdato de amônio como o molibdato de sódio podem ser indistintamente utilizados (SILVA et al, 1998).…”

Foliar Application of Calcium and Molybdenum in Common Bean Plants: Yield and Seed Physiological Potential

“…It is important for plants in seed production systems to have sufficient molybdenum because the poor pollinization that is associated with molybdenum deficiency may result in lower yield due to lower fertilization rates. Some studies have shown that the yield obtained from plants that have had foliar applications of molybdenum is higher than plants that have not [11]. Since, foliar application of molybdenum has been shown to efficiently increase the seed molybdenum content; however, no improvement has been observed for seed germination and vigor [12] [13].…”