ABSTRACT This work aims to study the status of silicon (Si) as a plant nutrient in the soil of Bahtim long-term field experiment in Egypt under the effect of crop rotations system and continuous fertilization. The experiment has been set up since 1912 based on two main factors: (1) crop rotations: mono-cropping (MC), two-year rotation (2Y-R), and three-year rotation (3Y-R), and (2) Fertilization: mineral nitrogen N, phosphorus P, potassium K, and organic farmyard manure FYM. Available N, P, K, and Si in soil were estimated. Productivity of soil was evaluated using Berseem (Trifolium alexndrinum L.) cultivated and harvested in 2019. The plant-available Si (PAS) in soil decreased significantly compared to the control C in case of MC by 70.26%, 2Y-R by 85.09%, and 3Y-R by 92.65% in the direction of N > NP > NPK. Mineral fertilization decreased the PAS significantly by 12.84% N, 29.52% NP, 78.45% NPK compared to the control C in the order of MC > 2Y-R > 3Y-R. Berseem yield (t ha−1) increased significantly compared with the control C following the order C < N < NP < NPK. The most significant increase in the yield was recorded for the NPK treatments by 224.04%, and 200% in case of MC, 2Y-R, 3Y-R, respectively.

中文翻译：

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97 年永久性试验中作物轮作和连续施肥对土壤中可用硅 (Si) 状态的影响

摘要 本工作旨在研究在轮作制度和连续施肥的作用下，在埃及 Bahtim 长期田间试验土壤中作为植物养分的硅 (Si) 状态。该试验自 1912 年以来基于两个主要因素进行：(1) 轮作：单作 (MC)、两年轮作 (2Y-R) 和三年轮作 (3Y-R)，以及 ( 2）施肥：矿质氮N、磷P、钾K、有机农家肥FYM。估算了土壤中的有效氮、磷、钾和硅。使用 2019 年栽培和收获的 Berseem (Trifolium alexndrinum L.) 评估土壤生产力。 与对照 C 相比，MC 情况下土壤中的植物有效硅 (PAS) 显着下降 70.26%，2Y-R 下降 85.09% , 3Y-R 在 N > NP > NPK 方向上增加了 92.65%。与对照 C 相比，矿物施肥使 PAS 显着降低了 12.84% N、29.52% NP、78.45% NPK，按照 MC > 2Y-R > 3Y-R 的顺序。Berseem 产量 (t ha-1) 与对照 C 相比显着增加，顺序为 C < N < NP < NPK。NPK 处理的产量增加最显着，分别为 224.04% 和 200%（MC、2Y-R、3Y-R）。