Virus-induced gene silencing (VIGS) is a genetic tool used to assess gene function. Tobacco rattle virus (TRV) is a VIGS vector commonly used to induce endogenous gene silencing in plants. However, there is no VIGS system established for Centaurea spp. We evaluated the effectiveness of a TRV-based VIGS system using phytoene desaturase (PDS) as a reporter gene in Centaurea cyanus. Three methods including pressure-, vacuum- and apical meristem-infiltration were tested to infect C. cyanus seedlings. Photobleached leaves were only obtained using apical meristem-infiltration after a 14 d treatment. The CcPDS transcripts in photobleached leaves were significantly reduced compared with that in green leaves treated with empty TRV. Four C. cyanus cultivars were tested to detect their VIGS responses, and ‘Dwarf Tom Pouce Blue’ was the most sensitive. The agro-infiltration condition was optimized by screening for the optimal seedling stage as well as the optimum Agrobacterium density for efficient silencing. Seedlings with four true leaves and infiltration with an Agrobacterium density of OD₆₀₀ 0.5 were optimal conditions to obtain more photobleached leaves and more intense photobleached phenotype. The results demonstrated the feasibility of TRV-based VIGS for functional analysis of genes in C. cyanus.

病毒诱导的基因沉默（VIGS）是一种用于评估基因功能的遗传工具。烟草吵闹病毒（TRV）是VIGS载体，通常用于诱导植物中的内源基因沉默。但是，尚没有针对矢车菊属物种建立的VIGS系统。我们评价了使用植体脱氢酶（PDS）作为矢车菊的报告基因的基于TRV的VIGS系统的有效性。测试了三种方法，包括压力，真空和顶端分生组织浸润，以感染蓝衣锦葵幼苗。经过14天处理后，仅使用根尖分生组织浸润获得了光漂白的叶片。该CCPDS与用空TRV处理的绿叶相比，光漂白叶中的转录本显着减少。测试了四个C. cyanus品种，以检测它们的VIGS响应，其中“矮矮胖汤姆·布鲁·蓝”最为敏感。通过筛选最佳苗期和最佳农杆菌密度以实现有效沉默，优化了农业渗透条件。具有四片真叶的幼苗和农杆菌密度为OD ₆₀₀ 0.5的浸润是获得更多光漂白叶和更强光漂白表型的最佳条件。结果证明了基于TRV的VIGS在蓝藻基因功能分析中的可行性。