Abstract

This study was developed to investigate if Ca and Mg silicate application as Si source combined with inoculation with Azospirillum brasilense and N rates can affect corn nutrient uptake. The study was set up in a Rhodic Hapludox under no-till system, located in Selvíria, state of Mato Grosso do Sul, Brazil. Treatments included: (i) two seed inoculation (with and without A. brasilense); (ii) two soil amendment sources (Ca and Mg silicate as Si source and dolomitic limestone); and (iii) five N application rates applied as side-dress (0 to 200 kg ha⁻¹). Increasing N rates positively influenced corn nutrition with increased nutrient and Si uptake in shoot and grain. The average nutrient uptake in descending order was K > N > Ca > Si > Mg > S > P >Fe > Mn > Zn > Cu > B for shoot and N > K > P > S > Mg > Ca > Si> Fe > Zn > Mn > B > Cu for grain. Calcium and Mg silicate application positively influenced corn nutrition with greater shoot P, K, Ca, S, and B uptake and grain Ca uptake. Inoculation with A. brasilense was found to increase nutrient uptake with greater shoot N, K, Ca, B, and Si and grain Cu uptake. Grain N and S increased by 22.5 and 26.8% when plants were inoculated and 200 kg N ha⁻¹ was applied and grain Zn increased by 88.6, 65.7, and 99% when plants were inoculated and 50, 150, and 200 kg N ha⁻¹ were applied, respectively. Therefore, studies conducted under tropical conditions are needed to better understand the role of Si combined with PGPB inoculation under different N management and their effects on plant nutrition and cereal development aiming at improving nutrient replenishment.

摘要

本研究旨在调查作为硅源的钙和镁硅酸盐应用与巴西固氮螺菌和 N 率的接种相结合是否会影响玉米养分吸收。该研究在位于巴西南马托格罗索州塞尔维里亚的免耕系统下的 Rhodic Hapludox 中进行。处理包括：（ⅰ）2种子接种（有和没有甲。brasilense）; (ii) 两种土壤改良源（硅酸钙和硅酸镁作为硅源和白云质石灰石）；(iii) 五种施氮量作为副肥施用（0 至 200 kg ha ^-1）。增加氮肥率对玉米营养产生积极影响，增加了地上部和谷物中养分和硅的吸收。平均养分吸收量按降序排列为 K > N > Ca > Si > Mg > S > P > Fe > Mn > Zn > Cu > B 和 N > K > P > S > Mg > Ca > Si > Fe > Zn > Mn > B > Cu 对于晶粒。施用硅酸钙和硅酸镁对玉米营养有积极影响，茎秆 P、K、Ca、S 和 B 吸收量增加，谷物 Ca 吸收量增加。发现接种 A. brasilense 可增加营养吸收，同时增加芽 N、K、Ca、B 和 Si 以及谷物 Cu 的吸收。接种植物和施用 200 kg N ha ^-1时，谷物 N 和 S 增加了 22.5% 和 26.8%，接种植物时谷物 Zn 增加了 88.6、65.7 和 99%，50、150、分别应用。因此，需要在热带条件下进行研究，以更好地了解 Si 与 PGPB 接种在不同氮管理下的作用及其对植物营养和谷物发育的影响，以改善营养补充。