Objective A model to comprehensively evaluate the nutritional quality of 14 Azolla germplasms was established to screen high-quality accessions resources with high protein content, rich amino acids, and balanced functional components.

Method Twenty-four contents of protein, essential amino acids, non-essential amino acids, and functional ingredients were selected as indicators to compare the nutritional quality of 14 azolla accessions selected from the 620 Azolla germplasm resources maintained at the National Azolla Germplasm Resource Nursery (Fuzhou). A model was constructed using the principal component analysis (PCA) and validated by the membership function method (MFM) for comprehensive evaluation of the various germplasms.

Result The quality indices varied significantly among the germplasms. Accession No. 3001 was significantly higher than No. 4018 and No. 7001 in the contents of protein, isoleucine, leucine, phenylalanine, threonine, valine, alanine, arginine, aspartic acid, glycine, histidine, proline, serine, and tyrosine. In PCA, it scored the highest at 3.84, and No. 7001 the lowest at −4.29; and in MFM, it also ranked the highest at 0.71, and No. 7001 the lowest at 0.17. The constructed evaluation model satisfactorily differentiated the nutritional quality of the 14 varieties of azolla plants, and No. 3001 was identified the best.

Conclusion It applied indicators that covered 4 essential categories of nutrients which identified Accessions No. 3001, PCGL, No. 4058, No. 2002, and No. 500 to be the superior varieties. In addition, the model showed Accession No. 3001 with high protein content, abundant amino acids, and balanced functional components to be of choice as a plant-based quality protein forage and of value for the breeding and broadening utilization of the germplasms.