Effectiveness of biofertilizers foliar application on yield and quality traits of flax (Linum usitatissimum L.)

Flax is considered to be one of the most significant dual-purpose crops for oil and fiber production in Egypt and worldwide. Biofertilizers have a substantial impact on various metabolic processes, including increased photosynthesis, endogenous hormone levels, ion absorption, nucleic acid synthesis, and protein synthesis. These factors collectively contribute to the growth and development of plants. Therefore, this study aims to investigate how three biofertilizers (Algae extract, CMS as a by-product of yeast, and Metalosate multi minerals as amino acids) can enhance both the quantity and quality of flax seed yield under sandy soil conditions. Two field experiments were conducted at the Experimental Station of National Research Centre in Nubaria District, Behira Governorate, Egypt during two seasons (2021/2022) using a randomized complete block design (RCBD). The results revealed significant differences among all tested biofertilizers in terms of various characteristics studied in flax. Foliar application of algae extract at a rate of 1.50 ​mL/L resulted in an increase in seed yield (ton/ha) by 26.69% & 19.89%, straw yield (ton/ha) by 8.08% & 17.12%, and oil yield (kg/ha) by 47.72% & 33.69% compared to the control group during both seasons respectively. Foliar applications of algae extract at a rate of 1.5 ​mL/L along with CMS at a rate of 5 ​mL/L and amino acids at a rate of 1.5 ​mL/L demonstrated significantly higher macronutrient contents (N, P, K), micronutrient contents (Fe, Zn, Mn), seed oil content, and protein content in flax seeds during both seasons. The highest values for seed oil content and protein content % were obtained through foliar application of amino acids at a rate of 1.50 ​mL/L. It can be concluded that foliar sprays with these biofertilizers effectively improved flax performance by increasing seed straw and oil yields, nutrients oil, protein and fatty acids seeds contents.