Ag doped hollow TiO2 nanoparticles as an effective green fungicide against Fusarium solani and Venturia inaequalis phytopathogens
Ag doped hollow TiO2 nanoparticles as an effective green fungicide against Fusarium solani and Venturia inaequalis phytopathogens
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DOI：
10.1088/0957-4484/27/8/085103
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发表时间：
2016-02-26
期刊：
影响因子：
3.5
通讯作者：
Paria, Santanu
中科院分区：
文献类型：
--
作者：
Boxi, Siddhartha Sankar;Mukherjee, Khushi;Paria, Santanu
化学杀虫剂广泛用于农业，以保护作物免受虫害和疾病的侵害。然而，高毒性农药的过度使用会导致一些人类健康（神经系统，肿瘤，癌症）和环境问题。因此，近年来，基于纳米颗粒的绿色农药变得特别重要。研究了纯TiO 2纳米粒子和Ag掺杂TiO 2纳米粒子（实心和空心）对两种植物病原菌Fusarium solani（导致马铃薯、番茄等枯萎病）和Venturia inaequalis（导致苹果黑星病）的抗真菌活性，发现空心纳米粒子比其他两种更有效。在可见光照射下，纳米颗粒对这两种植物病原菌的抗真菌活性进一步增强。纳米颗粒的杀菌效果取决于不同的参数，如颗粒浓度和可见光强度。纳米粒对苹果根瘤菌和黄瓜枯萎病菌的最小抑菌量分别为0.05mg/L和0.05mg/L。solani分别为0.75和0.43 mg/板。Ag作为掺杂剂的存在有助于在细胞蛋白中形成稳定的Ag-S和二硫键（R-S-S-R），这导致细胞损伤。在氧化过程中产生的（OH）-O-中心自由基使细胞壁结构松散，最终导致细胞死亡。纳米粒子对这两种植物病原体的杀菌作用的机制支持缩二脲和三苯基四氮唑氯化物分析和场发射电子显微镜。除了杀真菌作用外，在非常低的剂量（0.015 mg/板）下，纳米颗粒成功地阻止了对F.与真菌致病性有关。纳米颗粒被发现可以有效地保护受F.茄属或其它真菌腐败。
Chemical-based pesticides are widely used in agriculture to protect crops from insect infestation and diseases. However, the excessive use of highly toxic pesticides causes several human health (neurological, tumor, cancer) and environmental problems. Therefore nanoparticle-based green pesticides have become of special importance in recent years. The antifungal activities of pure and Ag doped (solid and hollow) TiO2 nanoparticles are studied against two potent phytopathogens, Fusarium solani (which causes Fusarium wilt disease in potato, tomato, etc) and Venturia inaequalis (which causes apple scab disease) and it is found that hollow nanoparticles are more effective than the other two. The antifungal activities of the nanoparticles were further enhanced against these two phytopathogens under visible light exposure. The fungicidal effect of the nanoparticles depends on different parameters, such as particle concentration and the intensity of visible light. The minimum inhibitory dose of the nanoparticles for V. inaequalis and F. solani are 0.75 and 0.43 mg/plate. The presence of Ag as a dopant helps in the formation of stable Ag-S and disulfide bonds (R-S-S-R) in cellular protein, which leads to cell damage. During photocatalysis generated (OH)-O-center dot radicals loosen the cell wall structure and this finally leads to cell death. The mechanisms of the fungicidal effect of nanoparticles against these two phytopathogens are supported by biuret and triphenyl tetrazolium chloride analyses and field emission electron microscopy. Apart from the fungicidal effect, at a very low dose (0.015 mg/plate) the nanoparticles are successful in arresting production of toxic napthoquinone pigment for F. solani which is related to the fungal pathogenecity. The nanoparticles are found to be effective in protecting potatoes affected by F. solani or other fungi from spoiling.