Search Results (3)

Aquilaria sinensis (Lour.) Gilg, the exclusive botanical source of Chinese agarwood, holds significant medicinal value. This study investigated the agarwood-inducing potential of a Fusarium strain obtained through prior isolation work. Through integrated morphological characterization and molecular phylogenetic analysis, the strain was conclusively identified as Fusarium equiseti. GC-MS analysis revealed that fungal inoculation induced the synthesis of characteristic sesquiterpenes and aromatic compounds consistent with natural agarwood profiles. Quantitative determination demonstrated progressive accumulation of agarotetrol, a key quality marker, reaching 0.034%, 0.039%, and 0.038% at 2, 4, and 6 months post-inoculation, respectively—significantly exceeding levels from physical wounding (p < 0.05) and PDA control treatments. Histological examination showed characteristic yellow-brown oleoresin deposits concentrated in the inner phloem, mirroring the anatomical features of wild-type agarwood. Critical quality parameters measured in December-harvested samples included ethanol extractives (17.69%), chromone derivatives 2-[2-(4-methoxyphenyl) ethyl] chromone, and 2-(2-phenylethyl) chromone (2.13%), all meeting or surpassing the specifications outlined in the National Standard for Agarwood Classification (LY/T 3223-2020). These comprehensive findings establish F. equiseti as a promising microbial agent for sustainable agarwood production in A. sinensis plantations. Full article

This study investigates the main insects and endophytic fungi that promote the formation of agarwood in Aquilaria sinensis (Lour.) Spreng. and elucidates the effects and mechanisms of different ‘insect + fungus’ combinations on agarwood formation. The results showed that 16 strains of endophytic fungi were isolated from A. sinensis. Fusarium solani, Penicillium chrysogenum, Fusarium equiseti, and Phaeoacremonium alvesii were identified as dominant fungi promoting agarwood formation, while Nadezhdiella cantori was recognized as the dominant insect facilitating this process. The optimal ‘insect + fungus’ combination was Nadezhdiella cantori + Fusarium equiseti. The average agarotetrol contents were 0.046% and 0.054% in February and June, respectively, which were significantly higher than those in cold drilling, fungal-only, and insect-only treatments. RNA sequencing revealed 23,801 differentially expressed unigenes in cjYB1Z4 (optimal combination) versus control BMZ. Upregulated unigenes were enriched in isoflavone biosynthesis, flavonoid biosynthesis, and sesquiterpenoid and triterpene biosynthesis. Fifty sesquiterpene-related differential unigenes encoded seven key enzymes in the MVA pathway, seven key enzymes in the MEP pathway, and seven terpene synthases. Co-expression network analysis indicated that transcription factors (e.g., WRKY33, ABF, WRKY2) potentially regulate agarwood sesquiterpene formation. This work elucidates preliminary effects and molecular mechanisms of insect- and fungi-induced agarwood formation in A. sinensis, advancing agarwood induction technology. Full article

Aquilaria crassna Pierre ex Lecomte is a principal species renowned for its production of agarwood. However, the active components of agarwood are not universally in compliance with the standards set by the Chinese Pharmacopoeia. We have identified an elite A. crassna tree with agarotetrol and alcohol extract levels that exceed these standards and have successfully established a stable in vitro micropropagation system using stem segments from this elite tree. The effects of auxins and minerals on axillary-bud induction, shoot multiplication, and rooting were investigated. The most effective medium for axillary-bud induction was a half-strength Murashige and Skoog (1/2MS) medium supplemented with 0.50 mg/L 6-benzylaminopurine (6-BA), achieving an induction rate of 53.33% with minimal hyperhydricity. The optimal shoot proliferation medium was an MS medium with 0.40 mg/L 6-BA, yielding a propagation coefficient of 2.96 without hyperhydricity. The best rooting medium comprised quarter-strength MS (1/4MS) macroelements and 1/2MS microelements with 0.10 mg/L naphthaleneacetic acid (NAA), resulting in an 82.54% rooting rate. Substrate effects on transplant survival and growth were also evaluated, and peat soil was identified as the best substrate, achieving a survival rate of 96.67%. This study introduces a straightforward and efficient in vitro micropropagation system utilizing mature A. crassna as explants. It holds significant importance for the consistent production of agarwood that complies with the standards of the Chinese Pharmacopoeia and provides a model for the targeted breeding of medicinal plants. Full article