O experimento foi conduzido em casa-de-vegetação, em vasos de 20 kg contendo solo de várzea. O objetivo deste trabalho foi avaliar o efeito de níveis, fontes e formas de aplicação do 382 cálcio na produção de biomassa, teores de açucares solúveis totais, açúcares redutores e na atividade da invertase e da carboxilase do fosfoenolpiruvato, em uma variedade de milho (BRS 4154) derivada do 14° ciclo de seleção para tolerância ao encharcamento transiente do solo, quando cultivada em solo encharcado. Entretanto, genótipos com tolerância ou resistência à hipoxia desenvolvem adaptações morfológicas e bioquímicas que podem ser utilizadas como marcadores para seleção de novos genótipos melhorados. Resumo: Baixas concentrações de oxigênio no solo, causadas pelo encharcamento ou alagamento temporário, reduzem a produtividade do milho. Key words: BRS 4154, transient waterlogging, invertase, PEPcase. Calcium application partially relieved the deleterious effect of waterlogging on biomass yield and the activities of INC, IAPC and PEPcase. Above ground biomass yield, the contents of total soluble sugars and reducing sugars and the activities of the neutral citosol (INC), acid vacuolar (IAV), acid cell wall invertases and phosphoenolpyruvate carboxylase were determined at the onset of flowering.
The effects of two sources of calcium (CaCl2, 300 kg ha-1 and CaSO4, 500 and 1.500 kg ha-1) and three modes of application (applied 8 cm below surface, mixed with the whole soil volume and surface application) were tested in soils kept at field capacity and waterlogged after plants reached growth stage V6. The study was carried out in a greenhouse, utilizing 20 kg pots, filled with a lowland soil. The objective of this work was to evaluate the effect of levels and modes of application of calcium sources on biomass yield, the contents of total soluble sugars and reduced sugars and on the activities of invertase isoforms and phosphoenolpyruvate carboxylase, in a maize variety (BRS 4154) derived from the 14th selection cycle for tolerance to transient soil flooding conditions, when cultivated under waterlogging conditions. However, genotypes with tolerance or even resistance to hypoxia develop morphological and biochemical adaptation mechanisms which may prove to be useful criteria for the selection and breeding of new improved genotypes. Purcino 2*Ībstract: Low soil oxygen concentrations due to waterlogging or transient flooding severely reduce maize production. Vasconcellos 2, Nelson Delú Filho 3, Daniela D. Купить СНПЧ А7 Архангельск, оперативня доставкаĬalcium Partially Relieves the Deleterius Effects of Hypoxia on a Maize Cultivar Selected for Waterlogging Tolerance