Composite plants containing transgenic hairy roots produced with Agrobacterium rhizogenes-mediated transformation have become an important method to study the interaction between plants and arbuscular mycorrhizal fungi (AMF). Not all hairy roots induced by A. rhizogenes are transgenic, however, which leads to requirement of a binary vector to carry a reporter gene to distinguish transgenic roots from non-transformed hairy roots. The beta-glucuronidase gene (GUS) and fluorescent protein gene often are used as reporter markers in the process of hairy root transformation, but they require expensive chemical reagents or imaging equipment. Alternatively, AtMYB75, an R2R3 MYB transcription factor from Arabidopsis thaliana, recently has been used as a reporter gene in hairy root transformation in some leguminous plants and can cause anthocyanin accumulation in transgenic hairy roots. Whether AtMYB75 can be used as a reporter gene in the hairy roots of tomato and if the anthocyanins accumulating in the roots will affect AMF colonization, however, are still unknown. In this study, the one-step cutting method was used for tomato hairy root transformation by A.rhizogenes. It is faster and has a higher transformation efficiency than the conventional method. AtMYB75 was used as a reporter gene in tomato hairy root transformation. The results showed that the overexpression of AtMYB75 caused anthocyanin accumulation in the transformed hairy roots. Anthocyanin accumulation in the transgenic hairy roots did not affect their colonization by the arbuscular mycorrhizal fungus, Funneliformis mosseae strain BGC NM04A, and there was no difference in the expression of the AMF colonization marker gene SlPT4 in AtMYB75 transgenic roots and wild-type roots. Hence, AtMYB75 can be used as a reporter gene in tomato hairy root transformation and in the study of symbiosis between tomato and AMF.

通过发根农杆菌介导的转化产生的含有转基因毛状根的复合植物已成为研究植物与丛枝菌根真菌（AMF）相互作用的重要方法。然而，并非所有由A. rhizogenes诱导的毛根都是转基因的，这导致需要二元载体携带报告基因以区分转基因根和未转化的毛根。β-葡萄糖醛酸酶基因（GUS）和荧光蛋白基因常被用作毛状根转化过程中的报告标记，但它们需要昂贵的化学试剂或成像设备。或者，AtMYB75 ，一种来自拟南芥的 R2R3 MYB 转录因子，最近已被用作一些豆科植物毛状根转化的报告基因，并可导致转基因毛状根中花青素的积累。AtMYB75是否可以作为番茄毛状根部的报告基因，根部积累的花青素是否会影响AMF的定植，目前尚不清楚。本研究采用一步切割法对发根土壤杆菌进行番茄毛状根转化。它比传统方法更快，转化效率更高。AtMYB75被用作番茄毛状根转化的报告基因。结果表明，AtMYB75过表达引起转化的毛状根中花青素的积累。转基因毛状根中花青素的积累不影响丛枝菌根真菌摩西漏斗菌 BGC NM04A 的定植，并且AtMYB75转基因根和野生型根中AMF 定植标记基因SlPT4的表达没有差异。因此，AtMYB75可作为番茄毛状根转化和番茄与AMF共生研究的报告基因。