Argyrochosma, a xeric-adapted fern genus mostly from the New World, includes both farinose and non-farinose species. The yellow farina appears to be a synapomorphy of A. flava. The aims of this research were to study the morphology, location, distribution, and density of glandular trichomes; perform a histochemical analysis of the farina secretion; evaluate the biological activity of farinas against phytopathogenic fungi; and characterize the species genetically by making chromosome counts and building the karyotype of A. flava. Usual methods in plant anatomy and histochemistry were performed. Minimum Inhibitory Concentrations (MICs) and Minimum Fungicidal Concentrations (MFCs) of farina against four phytopathogenic fungi were determined by the broth microdilution technique. Chromosome counts and karyotyping metaphase plates were obtained from fiddleheads. The distribution of glandular trichomes in pinnules changes along the ontogenetic development of the frond. The histochemical study of the trichomes revealed the complex nature of the secreted material, including flavonoids and terpenes along with other metabolites. The farina was active against the four pathogenic fungi evaluated, with MICs between 31.25 and 125 μg/mL showing the highest inhibition for Monilinia fructicola. Botrytis cinerea displayed a MIC value of only one-fold dilutions more than the commercial fungicide Carbendazim. Cytogenetically, the base number proposed for the genus is x = 27, which is derived from aneuploidy of x = 29. The genus has diploid and tetraploid forms. The results obtained support the important role of glandular trichomes and farinous exudate secretion in the protection against phytopathogenic fungi. The obtained chromosome numbers support the taxonomic placement of A. flava.

Argyrochosma是一种适应干旱的蕨类植物，主要​​来自新世界，包括含粉质和非含粉质物种。黄色淀粉似乎是黄曲霉的同源型。本研究的目的是研究腺毛的形态、位置、分布和密度；对淀粉分泌物进行组织化学分析；评估淀粉对植物病原真菌的生物活性；并通过进行染色体计数和建立黄曲霉的核型来表征该物种的遗传特征。进行了植物解剖学和组织化学中的常用方法。通过肉汤微量稀释技术测定了淀粉对四种植物病原真菌的最低抑制浓度（MIC）和最低杀菌浓度（MFC）。从蕨菜中获得染色体计数和核型分析中期平板。羽片中腺毛的分布随着叶体的个体发育而变化。毛状体的组织化学研究揭示了分泌物质的复杂性质，包括类黄酮和萜烯以及其他代谢物。淀粉对所评估的四种病原真菌具有活性，MIC 介于 31.25 至 125 μg/mL 之间，显示出对Monilinia fructicola 的最高抑制作用。灰葡萄孢 (Botrytis cinerea)的 MIC 值仅比商业杀菌剂多菌灵高一倍。在细胞遗传学上，建议该属的碱基数为x = 27，它源自x = 29 的非整倍性。该属有二倍体和四倍体形式。获得的结果支持腺毛和含粉分泌物分泌在防止植物病原真菌中的重要作用。获得的染色体数目支持黄曲霉的分类学位置。