Effects of Plant Density and Fertilization on Agronomic Traits and Yield of Flax (Linum usitatissimum L.)

Flax (<i>Linum usitatissimum</i> L.) is a retrovative crop with highly nutritious seeds. The study aimed to assess the effect of plant density and type of fertilizer on crop growth and productivity. A three-year experiment was conducted at the Agricultural University of Athens, focusing on two densities (D1 and D2) and four fertilizers (urea with inhibitors (I), organic (O), urea (U) and control (C)). Measurements included plant height, dry weight, number of capsules, number of seeds per capsule, Thousand Seeds Weight (TSW), yield, Harvest Index (HI), seed oil content and oil yield. Fertilization increased plant height (14.6-15.2%), dry weight (34.1%) and number of capsules (24.9%). D2 improved biomass production by 52.6%, while D1 increased the number of capsules by 16.4%. TSW increased by 6.7 and 23.9% at D2 and fertilized treatments, respectively. Yield, HI and oil yield were affected by the interaction of density and fertilization, while seed oil content was affected only by fertilization. D2I increased yield by 67.9% compared to D2C, while oil yield increased over twofold. Overall, flax represents a promising alternative crop against climate change in the Mediterranean Basin.