Ajmalicine Bioproduction in Catharanthus Roseus (L) G. Don Inoculated with Arbuscular Mycorrhiza and Fertilized with Nitrogen

ABSTRACT Catharanthus roseus (L) G. Don (Madagascar periwinkle) belongs to the Apocynaceace family and is widely spread throughout tropical and subtropical regions of the world. The plant produces several important alkaloids, such as ajmalicine and serpentine, which are used in the treatment of circulatory diseases. The potential of inoculation with arbuscular mycorrhizal fungi (AMF) and nitrogen fertilization to enhance the production of alkaloids was investigated in periwinkle. A greenhouse experiment was carried out to evaluate the effects of arbuscular mycorrhizal fungi and N fertilizer dosages on plant growth, production of ajmalicine, and nutrient content in roots. The concentration of ajmalicine was determined by reverse-phase high-performance liquid chromatography with UV detection. The experiment was designed in randomized blocks in a 4 × 4 factorial scheme with four microbiological treatments (control - without mycorrhiza; Claroideoglomus etunicatum; Rhizophagus intraradices; mixed inoculum - Rhizophagus clarus + Gigaspora margarita), and four N fertilizer dosages (15, 30, 60, and 120 mg kg-1) with four replications. Catharanthus roseus growth was higher when plants were inoculated with mixed inoculum (R. intraradices + G. margarita) and C. etunicatum. The mixed inoculum (R. intraradices + G. margarita) and C. etunicatum, combined with N fertilization, enhanced ajmalicine yield. Catharanthus roseus inoculated with mycorrhiza showed increased P absorption and reduced N content.

摘要：长春花（Catharanthus roseus (L) G. Don，又名马达加斯加长春花）隶属于夹竹桃科（Apocynaceae），广泛分布于全球热带与亚热带区域。该植物可合成阿马碱（ajmalicine）、蛇根碱（serpentine）等多种重要生物碱，用于循环系统疾病的临床治疗。本试验旨在探讨接种丛枝菌根真菌（arbuscular mycorrhizal fungi, AMF）与施加氮肥对提升长春花生物碱产量的潜在效果。通过开展温室盆栽试验，评估了丛枝菌根真菌接种及氮肥施用量对长春花生长、阿马碱产量以及根系养分含量的影响。采用反相高效液相色谱结合紫外检测法测定样品中阿马碱的浓度。试验采用4×4因子设计的随机区组方案，设置4种微生物处理（对照组：不接种菌根；幼套近明球囊霉（Claroideoglomus etunicatum）；根内根孢囊霉（Rhizophagus intraradices）；混合接种剂：透明根孢囊霉（Rhizophagus clarus）+玛咖巨孢囊霉（Gigaspora margarita））与4个氮肥施用量梯度（15、30、60、120 mg·kg⁻¹），每组设置4次重复。结果表明：接种混合接种剂（根内根孢囊霉+玛咖巨孢囊霉）与幼套近明球囊霉的长春花生长状况更佳；混合接种剂与幼套近明球囊霉配合氮肥施用时，可显著提升阿马碱产量；接种菌根的长春花植株磷吸收量显著提升，而植株氮含量有所降低。