Fontes de zinco aplicado em sementes de sorgo cv. BRS 310 e o crescimento inicial

Abstract

ResumoA aplicação de zinco em sementes de sorgo poderá afetar a nutrição e o crescimento inicial das plantas. Assim, objetivou avaliar a aplicação de zinco na forma de sulfato e de óxido sobre a nutrição e o crescimento inicial da planta do sorgo cv. BRS 310. Os tratamentos foram constituídos de cinco doses 0; 14,3; 28,6; 57,2 e 114,4 g kg -1 de semente e de duas fontes de zinco, o sulfato (22% de Zn) e o óxido (50% de Zn). Cada unidade experimental constituída de bandeja de polietileno translúcido preenchida com 5 L de areia grossa lavada, com 50 sementes do sorgo cv. BRS 310. Aos 25 dias após a semeadura, efetuouse o corte das plantas, avaliou-se a massa seca da parte aérea e das raízes e determinou-se o teor e o acúmulo de Zn nas plantas. A aplicação de zinco na forma de óxido promoveu maior incremento de matéria seca em plantas de sorgo e proporcionou maior eficiência de utilização do micronutriente, embora, com menor eficiência de absorção, quando comparado a fonte sulfato. A fonte sulfato causou diminuição na produção da massa seca do sorgo. As fontes promoveram alteração na absorção de outros nutrientes pelas plantas de sorgo, sendo que a fonte sulfato incrementou a absorção de P, Ca, S e Mn e a fonte óxido maior absorção de K, Mg, Cu e Fe. Palavras-chave: Sorghum bicolor, Zn, adubação, absorção AbstractThe zinc application in sorghum seeds can affect the nutrition and the initial growth of the plants. Thus, the objective of their study was to evaluate the zinc application in the form of sulphate and oxide on the nutrition and on the initial growth of the plant of sorghum cv. BRS 310. The treatments had been five rates 0; 14,3; 28,6; 57,2 and 114,4 g Zn kg -1 of seeds and two zinc sources, the sulphate (22% of Zn) and the oxide (50% of Zn). The experimental units were translucent polyethylene trays a filled with 5 L of washed thick sand, with 50 seeds of sorghum cv. BRS 310. The plants were cut 25 days after the sowing, and were evaluated for dry matter of above ground parts and the roots and it was determined the content and the accumulation of Zn in the plants. The zinc application in the oxide form promoted greater increment of dry matter in sorghum plants and provided to greater efficiency of use of the micronutrient, even so, with lesser efficiency of absorption, when compared the source sulphate. The source sulphate caused reduction in the production of the mass of the dry matter of sorghum. The sources had promoted alteration in the absorption of other nutrients for the sorghum plants, being that the source sulphate developed the absorption of P, Ca, S and Mn and the source oxide bigger absorption of K, Mg, Cu and Fe.

Effect of copper carbonate and zinc oxide applied to seeds on copper and zinc uptake by maize seedlings

“…However, comparing average results, plants tended to produce lower root biomass with the treatments containing only copper carbonate. These results differ from Luchese et al (2004) and Prado et al (2007), testing water-soluble sources based on copper and zinc sulphate salts, respectively. These authors verified that these sources reduced maize seed vigor, by negatively affecting seedling emergence and plants dry mass.…”

“…These sources generally differ in terms of water solubility, which is an important parameter that determines their uptake by plants (Amrani et al 1999;Shaver et al 2007;Salanenka and Taylor 2011). Prado et al (2007) compared two sources of zinc for maize seed treatment -zinc sulphate (water-soluble) and zinc oxide (water-insoluble) -and verified that the first is able to promote a higher uptake of zinc by plants. However, the same formulation reduced seedling emergence percentage, probably due to salinity excess, while zinc oxide did not present any harmful effect (Prado et al 2007).…”

“…Prado et al (2007) compared two sources of zinc for maize seed treatment -zinc sulphate (water-soluble) and zinc oxide (water-insoluble) -and verified that the first is able to promote a higher uptake of zinc by plants. However, the same formulation reduced seedling emergence percentage, probably due to salinity excess, while zinc oxide did not present any harmful effect (Prado et al 2007). Luchese et al (2004) found similar results by testing a copper sulphate formulation (water-soluble) as maize seed treatment, with a good uptake of copper by plants accompanied by toxic effects to seeds.…”

Assessing the Effectiveness of Zn Acetate and Oxide as Alternatives for Corn and Soybean Seed Treatment in Sandy and Clay Soil

“…Our results concur with this observation, showing that in sandy soil, corn and soybean fitted a linear response curve for the relationship between Zn accumulation and Zn application rates, as has been affirmed by Prado et al (2007) testing Zn rates using corn seed treatments. The addition of 1 g kg -1 of Zn, regardless of source, appears to have a positive effect on Zn accumulation and it is associated lower Zn level and clay concentration, before the experiment.…”

“…According to Prado et al (2007), Zn oxide is a more efficient means of increasing early corn growth compared to Zn sulfate. To date however, there have been no studies testing the potential for Zn acetate to be used as an alternative to seed Hídvégi and Lásztity (2002).…”