Potato plants are liable to PVY infection without efficient control. Therefore, they were cultivated under greenhouse and open field conditions, artificially infected with PVY and then treated after 15 days of infection with native lactoferrin (LF) and native β-lactoglobulin (BL) and their esterified forms, MLF (methylated lactoferrin) and BLM (methylated β-lactoglobulin) to test the efficiency of this approach. Viral replication was inhibited by the applied substances, particularly the methylated forms, in a concentration-dependent manner, where the concentration of 500 μg·mL⁻¹ was sufficient for plant protection against the PVY infection. An open field experiment showed that one single application of the antiviral substance was enough for maximum inhibitory action against PVY. The modified milk proteins induced higher inhibitory action on PVY virus replication in the plants, compared to their native forms, which was reflected by potato growth and yield. Using the dot blot hybridization and RT-PCR techniques to detect PVY in the experimental plants showed the supremacy of native and esterified LF in inhibiting the targeted virus. The generally observed scanning electronic microscopy (SEM) structural deformations and irregular appearance in PVY particles when treated with MLF and BLM revealed their direct action. BLM, MLF and LF are efficient antiviral agents against PVY. They can not only abolish the observed PVY-induced reduction in potato growth and tuber yield, but also further increase them to higher levels than negative control.

中文翻译：

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天然和甲基化的乳铁蛋白和β-乳球蛋白对马铃薯Y病毒（PVY）的侵染作用，该病毒被侵染于开放田地中的马铃薯植株中。

马铃薯植株容易受到PVY感染，而没有有效的控制。因此，它们在温室和露天条件下进行栽培，人工感染PVY，然后在天然乳铁蛋白（LF）和天然β-乳球蛋白（BL）及其酯化形式MLF（甲基化乳铁蛋白）和BLM感染15天后进行处理（甲基化β-乳球蛋白）来测试这种方法的效率。所施加的物质（特别是甲基化形式）以浓度依赖的方式抑制病毒复制，浓度为500μg·mL ^-1足以保护植物免受PVY感染。露天实验表明，单次使用抗病毒物质足以对PVY发挥最大抑制作用。与马铃薯的天然形式相比，修饰的牛奶蛋白质对植物中的PVY病毒复制具有更高的抑制作用，这可以通过马铃薯的生长和产量来体现。使用斑点印迹杂交和RT-PCR技术检测实验植物中的PVY，表明天然和酯化LF在抑制目标病毒方面具有至高无上的地位。用MLF和BLM处理后，通常观察到的扫描电子显微镜（SEM）结构变形和PVY颗粒中的不规则外观显示出它们的直接作用。BLM，MLF和LF是针对PVY的有效抗病毒药。