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较近，来自比利时根特大学的专家利用WIWAM XY植物表型系统发表了题为Arabidopsis thaliana GRF3-like transcription factors under different growth conditions的文章，发表在植物学先进期刊New Phytologist上。利用WIWAM XY较早进行拟南芥研究的文章发表在Nature Biotechnology上，影响因子高达40。

作为先进家将大规模自动化理念和工业级零件和设备整合入植物成像系统的厂家，SMO公司在植物表型成像分析领域处于先进的技术前列，大面积叶绿素荧光成像系统使WIWAM成为植物表型分析与功能成像领域较为先进的仪器设备，植物生长、胁迫响应等测量参数达几百个。工业级部件品质使系统非常耐用，基本免维护，与同类产品相比，特点突出。目前WIWAM植物表型平台分为WIWAM XY，WIWAM Line以及WIWAM Conveyor 3个系列。野外移动版称为WIWAM Screening。

WIWAM XY是一款高通量可重复性表型机器人， 用于对小型植物, 如拟南芥植物的研究。该机器人可定期对多种植物参数进行自动化灌溉和并测量多种植物生长参数。WIWAM XY代替了很多手工处理，省时省钱，精度较高。

北京欧亚国际科技有限公司是比利时WIWAM植物表型成像系统中国区总代理，全面负责其系列产品在中国市场的推广、销售和售后服务。

Arabidopsis thaliana GRF3-like transcription factors under different growth conditions

Arabidopsis thaliana GRF3-like transcription factors under different growth conditionsMatías Beltramino1, María Florencia Ercoli 1, Juan Manuel Debernardi1, CamilaGoldy1,Arantxa M. L. Rojas1, Florencia Nota2,3, María ElenaAlvarez 2,3, LiesbethVercruyssen4,5,Dirk Inzé 4,5, Javier F. Palatnik1,6 & Ramiro E. Rodriguez 1,6 

An increase in crop yield is essential to reassure food security to meet the accelerating global demand. Several genetic modifcations can increase organ size, which in turn might boost crop yield. Still, only in a few cases their performance has been evalsuated under stress conditions. MicroRNA miR396 repress the expression of GROWTH-REGULATING FACTOR (GRF) genes that codes for transcription factors that promote organ growth. Here, we show that both Arabidopsis thaliana At-GRF2 and At-GRF3 genes resistant to miR396 activity (rGRF2 and rGRF3) increased organ size, but only rGRF3 can produce this efect without causing morphological defects. Furthermore, introduction of At-rGRF3 in Brassica  oleracea can increase organ size, and when At-rGRF3 homologs from soybean and rice are introduced in Arabidopsis, leaf size is also increased. This suggests that regulation of GRF3 activity by miR396 is important for organ growth in a broad range of species. Plants harboring rGRF3 have larger leaves also under drought stress, a condition that stimulates miR396 accumulation. These plants also showed an increase in the resistance to virulent bacteria, suggesting that the size increment promoted by rGRF3 occurs without an obvious cost on plant defenses. Our fndings indicate that rGRF3 can increase plant organ size under both normal and stress conditions and is a valuable tool for biotechnological applications.Te growth of plant organs is tightly controlled by their developmental program and the interaction with the environment. Leaves initiate as rod-like structures protruding from the shoot apical meristem, pass through diferent developmental stages and become a fat organ specialized in photosynthesis1,2 . Multiple regulatory gene networks are known to participate in the morphogenesis of a leaf, although their precise role and interactions are unknown in many cases.Crop yield is a highly complex trait infuenced by both external and internal factors. Intrinsic Yield Genes (IYG) have been defned as those genes that produce larger organs, such as leaves, roots or seeds, when mutated or ectopically expressed3. In this sense, the precise modifcation of IYG might increase crop yield and therefore they constitute a potential source of biotechnological applications. Te GROWTH-REGULATING FACTORs (GRFs) genes code for a family of plant-specifc transcription factors characterized by the presence of the WRC and QLQ protein domains, which have been involved in DNA-binding and protein-protein interaction, respectively4–9 . In Arabidopsis thaliana, there are nine GRF coding genes (GRF1-9). Seven out of them harbor a target site for microRNA miR396. At early stages of leaf development, miR396 is expressed in the distal part of the leaf, restricting the expression of the GRFs to the proximal part, which is coincidental with the proliferative region 1 IBR (Instituto de Biología Molecular y Celular de Rosario), CONICET and Universidad Nacional de Rosario, Rosario, Argentina. 2 CONICET, Universidad Nacional de Córdoba, Centro de Investigaciones en Química Biológica de Córdoba(CIQUIBIC), Córdoba, Argentina. 3 Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Departamento de Química Biológica Ranwel Caputto, Córdoba, Argentina. 4 VIB-UGent Center for Plant Systems Biology, VIB, 9052, Ghent, Belgium. 5 Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052, Ghent, Belgium. 6 Centro de Estudioses Interdisciplinarioses, Universidad Nacional de Rosario, Rosario, Argentina. Matías Beltramino,María Florencia Ercoli and Juan Manuel Debernardi contributed equally. Correspondence and requests for materials should be addressed to J.F.P. (email: palatnik@ibr-conicet.gov.ar) or R.E.R. (email: rrodriguez@ibr-conicet.gov.ar) throughout the organ repressing GRF expression in maturing organs10–12.Te miR396-GRF module is present in a broad range of plants including angiosesperms and gymnosperms11,14,15. In certain cases, the ectopic expression of the GRFs is sufcient to increase leaf size. In Arabidopsis, overexpression from the 35S promoter of At-GRF516,17, Brassica napus Bn-GRF218 and Brassica rapa Br-GRF819 promotes a moderate increase of leaf size.Modified GRFs have been generated with synonymous mutations in the miRNA target site to avoid the post-transcriptional repression mediated by miR39612,20. The observation that plants harboring these miR396-resistant versions of At-rGRF2 (rGRF2) or At-rGRF3 (rGRF3) have larger leaves with respect to wild type plants, indicates that miR396 normally restricts organ size through the repression of the genes coding for GRF transcription factors. In good agreement with these results, plants overexpressing miR39612,21 or single grf517 and multiple grf1 grf2 grf35  knock outs have smaller organs.However, increased levels of the GRFs not always results in larger organs in Arabidopsis, as over expression of Oryza sativa Os-GRF1 caused pleiotropic defects, including curled leaves, delayed fowering and defects in carpel development 4 . Results in crops have also been variable. Overexpression of Zm-rGRF1 increased maize leaf size, while it also caused additional detrimental phenotypes such as large macrohairs covering the glumes and the ear rachis that reduced fertility15, while overexpression of Zm-GRF10, which lacks a transactivation domain, reduced maize leaf size22. Furthermore, high levels of At-GRF7 and At-GRF9 caused no major increase of Arabidopsis leaf size23–25. Interestingly, At-GRF7 has been implicated in the response of plants to osmotic stress23, while At-GRF9 has been claimed to be a growth repressor26. Furthermore, in certain organs and conditions, the GRFs can afect both cell number and size27,28. Te capacity of certain GRFs to increase leaf size per se suggests that they can act as IYG increasing plant organ size, and therefore they could be a valuable tool for biotechnological applications. Still, not all the GRFs have a positive impact on organ size, and some of them have even deleterious efects. Here, we characterized different members of the GRF family in Arabidopsis and found that the At-GRF3 gene decoupled from miR396 regulation consistently increase organ size in Arabidopsis thaliana, an ability that likely depends on the protein sequence of the transcription factor. We also show that a miR396-resistant GRF3 can increase leaf size, root length and seed size in transgenic Brassica oleracea. Furthermore, we found that plants expressing the rGRF3 transgene still have an increase in leaf size under mild drought stress and show enhanced resistance to certain plant pathogens. We conclude that GRF transcription factors similar to At-GRF3 can be used to increase plant organ size in Brassicaceae species without an obvious deleterious impact in plant fitness.