Autotoxicity is a principal cause of growth inhibition in monocultures. Autotoxicity in monocropped cucumber limits plant growth, which causes an obvious reduction in yield and quality in cucurbit crops. Cinnamic acid is a major autotoxin that has been used to mimic autotoxicity in cucumber. The long hairpin RNA (lhRNA) library of Arabidopsis was screened in cinnamic acid (CA) mimicked autotoxicity to obtain autotoxicity-resistant mutant lines. We found that a new gene, At5g16610, whose function is unknown, was silenced in the resistant mutant line HCA350–597, and the homologous gene of Arabidopsis At5g16610 (NM_203062.2), whose function is also unknown, was cloned in cucumber and named CsARR-9 (Cucumis sativus Autotoxicity Resistance Related). Here, we silenced the CsARR-9 gene using an established tobacco rattle virus (TRV) mediated virus-induced gene silencing (VIGS) system, and the CsARR-9 gene was also silenced by RNA interference in cucumber. We found that this silencing resulted in decreased CsARR-9 expression in both leaves and roots enhanced tolerance to autotoxicity mimicked by CA. Resistance to CA-mimicked autotoxicity was achieved by reductions in the CA concentrations in roots, stems and leaves, which maintained the structural integrity of cells and tissue within an organ system, promoted cell vigor, enhanced thylakoid stacking and increased the storage of photosynthetic products in chloroplasts, and these effects promote the growth of CsARR-9-silenced cucumber plants. These findings provide a valuable genetic resource for research regarding continuous cropping obstacles, especially in monocultures, and insights on the related molecular mechanism, and have important practical significance for prolonging the planting years and the efficient use of facility agriculture.

自毒性是单一培养物中生长抑制的主要原因。单作黄瓜的自毒作用限制了植物的生长，导致葫芦类作物的产量和品质明显下降。肉桂酸是一种主要的自毒素，已被用于模拟黄瓜的自毒性。拟南芥的长发夹RNA (lhRNA) 文库在肉桂酸(CA) 模拟自毒作用中进行筛选，以获得抗自毒作用的突变株系。我们发现一个功能未知的新基因At5g16610在抗性突变株系HCA350-597中被沉默，并且在黄瓜中克隆出功能未知的拟南芥同源基因At5g16610（NM_203062.2）并命名为CsARR-9 (Cucumis s ativus A utotoxicity R resistance相关）。_ 在这里，我们使用已建立的烟草脆裂病毒 (TRV) 介导的病毒诱导基因沉默 (VIGS) 系统沉默了 CsARR-9 基因，并且 CsARR - 9基因也被黄瓜中的 RNA 干扰沉默了。我们发现这种沉默导致CsARR-9减少叶和根中的表达增强了对 CA 模拟的自毒性的耐受性。通过降低根、茎和叶中的 CA 浓度来实现对 CA 模拟自毒性的抗性，这可以维持器官系统内细胞和组织的结构完整性，促进细胞活力，增强类囊体堆积并增加光合产物的储存叶绿体，这些作用促进了CsARR-9沉默的黄瓜植物的生长。这些发现为研究连作障碍特别是单一栽培障碍及其相关分子机制提供了宝贵的遗传资源，对延长种植年限和设施农业的高效利用具有重要的现实意义。