Rice grown in nutrient solution with doses of manganese and silicon

Abstract

SUMMARYAlthough silicon is not recognized as a nutrient, it may benefit rice plants and may alleviate the Mn toxicity in some plant species. The dry matter yield (root, leaf, sheaths and leaf blade) and plant architecture (angle of leaf insertion and leaf arc) were evaluated in rice plants grown in nutrient solutions with three Mn doses, with and without Si addition. The treatments were arranged in a 2 x 3 factorial [with and without (2 mmol L -1 ) Si; three Mn doses (0.5; 2.5 and 10 μmol L -1 )], in a randomized block design with 4 replications. The experimental unit was a 4 L plastic vase with 4 rice (Metica-1 cultivar) plants. Thirty nine days after keeping the seedlings in the nutrient solution the plant dry matter yield was determined; the angle of leaf insertion in the sheath and the leaf arc were measured; and the Si and Mn concentrations in roots, sheaths and leaves were determined. The analysis of variance (F test at 5 and 1 % levels) and the regression analysis (for testing plant response to Mn with the Si treatments) were performed. The Si added to the nutrient solution increased the dry matter yield of roots, sheaths and leaf blades and also decreased the angle of leaf blade insertion into the sheath and the foliar arc in the rice plant. Additionally, it ameliorated the rice plant architecture which allowed an increase in the dry matter yield. Similarly, the addition of Mn to the solution improved the architecture of the rice plants with gain in dry matter yield. As Si was added to the nutrient solution, the concentration of Mn in leaves decreased and in roots increased thus alleviating the toxic effects of Mn on the plants.Index terms: Oryza sativa, mineral plant nutrition, beneficial element.

Influence of Potassium Silicate on Water Deficit Tolerance for Some Rice Genotype تأثير سلکيات البوتاسيوم لتحمل نقص الماء لبعض الطرز الوراثية لمحصول الارز

“…The increase in silica levels led to the plants being more erect and reduced the self-shading of lower leaves of the canopy, which made the plants more photosynthetic efficient and better able to exploit the space available to intercept solar radiation, consequently increasing leaf area index, dry matter, and plant height. A similar result was found by Zanão Júnior et al (2010), De Oliveira et al (2016), Wissa. (2017 and Mikhael et al (2018).…”

Silicon sources for studies of rice plants in nutrient solutions

“…A dose of 2 mmol L -1 Si added to the nutrient solution, regardless of Si source, increased dry matter yield of shoots (DMYS), roots (DMYR), leaf area, and leaf specific mass (LSM) of rice plants (Table 2). The significant increase of LA, DMYS, and DMYR in rice in response to Si application observed in this work was also observed by several other authors (CHAGAS et al, 2016;MAUAD et al, 2011;ZANÃO JÚNIOR et al, 2010). Rice plants treated with Si accumulate significant amounts of this beneficial element in leaves resulting in a larger leaf area.…”

“…The supply of Si to rice plants brings many benefits such as higher grain yields and enhanced resistance to biotic and abiotic stresses conditions, for instance diseases, pests, drought, salinity, and toxicity caused by Al, Mn, Fe, and other metals (ZANÃO JÚNIOR et al, 2009;KIM et al, 2015;GONG, 2014).…”

Produção de rosas influenciada pela aplicação de doses de silício no substrato

“…Esses resultados coincidiram com vários relatos na literatura e reafirmaram um dos maiores benefícios do Si, que é a redução da toxidez por teores elevados de Mn (Iwasaki et al, 2002;Rogalla & Römheld, 2002;Zanão Júnior et al, 2010). Esses autores também verificaram menores teores de Mn nas folhas de plantas supridas com Si.…”