Morphological, biochemical and fatty acid variations of three perilla (Perilla frutescens L.) cultivars under open-field conditions in Northern China

Perilla ( perilla frutescens L.) is an economically significant oilseed crop valued for its high α-linolenic acid (ALA) content and nutritional properties. Optimizing genotype selection is crucial for improving oil yield and nutritional quality in diverse environments. This study evaluated morphological and biochemical variation of three perilla cultivars (Bing Zisu 1, Zhongbei Zisu 3 and Zhongbei Zisu 4) and hypothesized that genotype, year, and location significantly influence these traits, revealing distinct genotype-specific advantages. Field trials were conducted over two years (2022 and 2024) across five open-field locations in Shanxi Province, China. Significant genotypic differences were observed. Zhongbei Zisu 4 exhibited late flowering and maturity, highest 1000 grain weight (3.66 g), protein (26.53 g/100 g), and oil (38.93 g/100 g) with low fiber (12.03%). Zhongbei Zisu 3 showed overall superior morphology and the highest ALA content (65.16%), while Bing Zisu 1 had the highest oleic acid content (22.12%) and crude fiber (15.8%). Planting year and location significantly ( p < 0.05) affected most morphological traits, with a 21.86% grain yield increase in 2024 compared to 2022. Grain yield positively correlated with several morphological and biochemical traits. Distinct genotype-specific strengths were identified, providing a foundation knowledge for targeted breeding and selection strategies. • Morphological and biochemical traits of perilla cultivars in different locations over two years were evaluated. • There are correlations in agronomic traits among different cultivars. • Zhongbei Zisu 3 is optimal for α-linolenic acid content and biomass. • Zhongbei Zisu 4 is optimal for high-value oil and protein.