Impact of spring and summer cultivation on broccoli seed quality and bioactive composition

Abstract

Background: Broccoli (Brassica oleracea var. italica) is a nutritionally and medicinally valuable crop, rich in vitamins (C, B, A, E), minerals, phenolic compounds, flavonoids, glucosinolates, and other bioactive constituents. These compounds contribute to antioxidant, anticancer, anti-inflammatory, and immune-supporting properties, making broccoli seeds particularly relevant for functional food applications. In Armenia, broccoli cultivation is expanding, but seed quality and bioactive composition are strongly influenced by seasonal cultivation conditions, temperature, and water availability.

Objective: This study aimed to evaluate the impact of spring and summer cultivation in the Ararat Valley on the physical, chemical, and biological properties of broccoli seeds, with a focus on their nutritional and functional potential.

Methods: The ‘Hayasa’ cultivar was grown under spring and summer field conditions. Phenological observations, seed yield, and biometric parameters were recorded. Seed quality was assessed by germination percentage, germination energy, and seedling viability. Chemical analyses included vitamins C, A, B1, B2, B6, E, total phenolic compounds, soluble sugars, and mineral (ash) content, using spectrophotometric and colorimetric methods. Data were statistically analysed by ANOVA with four replications.

Results: Spring-grown seeds exhibited higher germination rates (92.3%), greater germination energy (85.3%), and superior seed mass (3.6 g/1000 seeds) compared to summer-grown seeds (germination 80.3%, energy 70%, seed mass 2.9 g/1000 seeds). Spring seeds also contained higher levels of vitamin C (49.1 mg/100 g DW), β-carotene (3.6 mg/100 g DW), B-group vitamins (0.43 mg/100 g), total phenolics (4.5–6.0 mg/g DW), soluble sugars (30–35%), and ash/mineral content, while summer seeds showed elevated vitamin E (4.6 mg/100 g DW) and total phenolics (6.0–8.0 mg/g DW), likely as a stress response to high temperature and solar radiation.

Novelty: This is the first comprehensive assessment of broccoli seed quality under different seasonal cultivation regimes in the Ararat Valley, integrating physical, chemical, and biological properties. The study demonstrates how environmental conditions modulate functional compounds in seeds, linking agronomic practices to health-promoting potential.

Conclusion: Spring cultivation provides optimal conditions for producing broccoli seeds with superior biological value, germination quality, and functional composition, suitable for agricultural propagation and functional food applications. Summer cultivation reduces seed quality but induces stress-related increases in specific bioactive compounds, highlighting the importance of seasonal management strategies to maximize functional food potential.

Keywords: broccoli seeds, vitamins, total phenolics, functional foods, seasonal cultivation