Interaction with soil enhances the toxic effect of iodide and iodate on barley (Hordeum vulgare L.) compared to artificial culture media during initial growth stage

Iodine is an essential trace element for humans, and while plants play an important role in its supplementation, they can also be subject to iodine toxicity. Herein, comparison of iodide and iodate effects on barley (Hordeum vulgare L.) development was evaluated in laboratory experiments when it was cultivated in iodine-spiked agar cultivation media and agricultural soil. Our results show that iodine toxicity is highly dependent on its chemical form and also reflects growth substrate type. Barley responses to iodine presence in agar and soil media suggest that iodide has more severe inhibitory effects than iodate on plant growth. Furthermore, the detrimental effect of iodine notably increased in soil with biomass synthesis as the most sensitive physiological parameter to adverse iodide and iodate effects. However, mild iodate and iodide stimulation of barley growth was observed which implies they are beneficial for growth at low concentrations. These effects were more intense when iodine was applied as iodide, especially in soil cultivation system where natural geochemical processes lead to alteration in iodine speciation which significantly increases plant sensitivity to iodine toxicity.     

马铃薯锌营养特性及锌生物强化技术研究进展

锌是植物和人体必需的微量元素,锌缺乏是全球公共健康问题。在马铃薯主粮化背景下,探讨马铃薯锌营养特性及锌生物强化技术手段对实现马铃薯富锌、改善人体缺锌状况具有重要意义。本文从马铃薯锌营养功能、马铃薯产区土壤锌状况、育种以及农艺强化技术等方面进行了综述和展望,提出锌对马铃薯生长及产量和品质形成具有重要作用,农艺强化是目前马铃薯锌营养强化主要技术措施,育种强化需要进一步发掘利用优异种质资源,旨在为科学利用锌生物强化技术实现马铃薯富锌提供一定的理论依据。     

生物源新型铁螯合剂研究进展及其应用

铁是所有生物正常发育所必需的微量元素之一，尤其是通过生物强化培育富含铁营养的农产品是解决人类铁营养“隐性饥饿”的重要技术途径，而螯合态铁肥由于见效快被广泛应用。因此，创制和研发新型微量元素螯合剂始终是国内外研究的竞争热点。麦根酸类植物铁载体和微生物铁载体等，能够高效螯合难溶铁并被植物高效吸收利用，是潜在的新型生物源螯合剂。该类新型铁肥在改善植物铁营养的同时不需要外源铁的投入，而是发挥菌株自身活性物质较强的螯合特性高效活化土壤中丰富的铁资源，为植物提供足够的生物有效铁。为进一步挖掘和研发新型生物源的绿色、高效且稳定的螯合剂，并为绿色智能肥料研发、实现绿色农业的可持续发展提供新途径和技术突破，本文基于近年来植物和微生物对铁营养吸收利用的分子生理机制的不断深入研究，从植物缺铁现状及诱因、改善铁营养的途径，到机理Ⅱ植物根系分泌物吸收利用铁的分子生态优势以及微生物铁载体改善植物铁营养的潜力，对生物源新型铁螯合剂研究进展及其应用进行了系统综述。期望通过进一步的研究和开发，能够更深入地了解这些新型生物源螯合剂的作用机制以提高植物的铁营养吸收效率，为实现绿色农业的可持续发展提供新的解决方案。     

叶面喷施硒酸钠对不同小麦品种(系)籽粒硒及其他矿质元素含量的影响

为了解叶面喷施硒酸钠对不同小麦品种(系)籽粒硒含量及其他矿质元素的影响,对114个不同小麦品种(系)进行叶面喷施硒酸钠,试验设4个梯度,分别为0 mg·kg~(-1)(CK)、100 mg·kg~(-1)(Se10)、200mg·kg~(-1)(Se20)、300mg·kg~(-1)(Se30),利用离子发射光谱-原子吸收仪测定了籽粒硒、钙、镁、铜、铁、锰、锌、硫含量。结果表明,叶面喷施硒酸钠可以提高小麦籽粒的硒含量,增幅因品种(系)而异;CK、Se10、Se20及Se30处理下,籽粒的总硒含量分别为1.54、5.70、10.01和13.10mg·kg~(-1)。籽粒中不同矿物质元素对叶面喷施硒酸钠的响应不同;籽粒中硒与其他元素的积累既有协同也有拮抗作用,因元素种类、小麦品种(系)和施硒量而异。总体而言,高浓度硒处理降低了籽粒中钙、镁、铜、铁、锰和硫的含量,但提高了锌的含量。