Fertilidade do solo na qualidade fisiológica de sementes de soja

Abstract

RESUMOO objetivo deste trabalho foi estudar, através de ferramentas da agricultura de precisão, a variabilidade da fertilidade do solo em campos de produção de sementes de soja e o efeito na qualidade fisiológica das sementes produzidas. Inicialmente, foi estabelecido um grid de amostragem de 1 ponto por hectare onde foram realizadas as coletas de amostras de solo e de sementes. No solo foram determinados teores de fósforo (P), potássio (K), cálcio (Ca), magnésio (Mg), matéria orgânica (%), argila (%), saturação de bases (%), saturação por alumínio (%), pH em água e CTC efetiva (CTC). Realizou-se a avaliação da qualidade fisiológica das sementes por meio dos testes de germinação, primeira contagem da germinação, envelhecimento acelerado e emergência de plântulas. A partir dos dados obtidos foram gerados os mapas de interpolação e a análise de correlação entre os fatores estudados. Observou-se a existência de variabilidade espacial em diferentes intensidades para os atributos químicos do solo avaliados e a qualidade fisiológica das sementes produzidas. Além disto, o incremento de Ca e da CTC efetiva contribui positivamente para a germinação de sementes de soja, enquanto a saturação por Al do solo afeta negativamente o vigor. Palavras-chave: agricultura de precisão, Glycine max (L.) Merrill, qualidade de sementes Soil fertility on the physiological quality of soybean seeds ABSTRACTThis study aimed to determine the variability of soil fertility in the fields of seed production and its effect on seed physiological quality of soybean seeds by precision agriculture tools. A sampling grid of 1 point per hectare was established, where soil and seed samples were collected. In soil samples were determined the concentrations of phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), organic matter (%), clay contents (%), bases saturation (%), aluminum saturation (%), pH and cation exchange capacity (CEC). Seed quality was evaluated by germination test, first count of germination, accelerated aging and seedling emergence. From the obtained data, interpolation maps were created, besides correlation analysis among the factors studied. Soil properties evaluated, as well as the seed physiological quality showed spatial variability at different concentrations. Furthermore, the increase of Ca and effective CEC positively affect the germination of soybean seeds, while Al saturation of the soil adversely affects the soybean seeds vigor.

Physiological quality of soybean seeds under different yield environments and plant density

“…In the studied field, although precision agriculture tools were adopted, including georeferenced soil sampling and variablerate fertilizer application, the HY was characterized by higher OM contents, P contents and CEC in all layers evaluated, compared with LY (Table 1). Mondo et al (2012) and Mattioni et al (2013) observed positive relationship between seed PQ and soil fertility. According to Panozzo et al (2009), plants originated from high-vigor seeds produce 17% more pods in comparison to those originated from low-vigor seeds.…”

“…Factors related to the environment in which the crop grows (low or high yield potential) and plant arrangement, such as plant density (PD), can also determine seed PQ (Vazquez et al, 2008;Mondo et al, 2012). In a soybean seed production field, Mattioni et al (2011Mattioni et al ( , 2013 and Gazolla Neto et al (2015) reported the presence of spatial variability in the vigor index. Similarly, studies have concluded that the organic matter content (Mondo et al, 2012), calcium content and soil CEC effective benefited the germination index (Mattioni et al, 2013).…”

“…In a soybean seed production field, Mattioni et al (2011Mattioni et al ( , 2013 and Gazolla Neto et al (2015) reported the presence of spatial variability in the vigor index. Similarly, studies have concluded that the organic matter content (Mondo et al, 2012), calcium content and soil CEC effective benefited the germination index (Mattioni et al, 2013). On the other hand, PD interferes with the intraspecific competition of plants, conditioning the individual yield (Luca & Hungría, 2014) and, therefore, possibly affecting PQ.…”

Influence of spatial soil variability on productivity and physiological quality of soybean seeds

“…This relationship identifies regions that produce seeds with higher physiological quality and regions that produce seeds with lower physiological quality. The same phenomenon has been observed in productivity (Mattioni et al, 2011;Mondo et al, 2012;Mattioni et al, 2013;Gazolla-Neto et al, 2016). However, defined management areas for the production of seeds and technology implementation have not yet been adequately elucidated.…”

Nota Técnica: Zonas De Manejo Nos Níveis De Fósforo E Potássio No Solo E a Produtividade De Arroz Irrigado

“…Indicando a heterogeneidade desses atributos na área em estudo. Vários pesquisadores (CAVALCANTE et al, 2007;DALCHIAVON et al, 2012;MATTIONI et al, 2013;GAZOLLA-NETO et al, 2015;GAZOLLA-NETO et al, 2016) também encontraram alta variabilidade espacial para o fósforo e potássio.…”