Comparative Growth of Oilseed and Textile Flax under Different Nitrogen Supplies

Abstract

The objective of this work was to compare and characterize the response to nitrogen (N) supply of a textile and an oilseed cultivar of flax (Linum usitatissimum L.). The dynamics of growth, biomass partitioning, growth rates, and leaf area evolution and duration of the cultivars Omega (oilseed) and Diane (textile) were compared under three rates of N supply. Plants were grown in pots in the field with nil (N1), 2.5 (N2), and 5 g N per pot (N3); N2 and N3 doses were divided into five applications. Shoot biomass of N2 and N3 treatments was similar in both cultivars and significantly higher than in N1. Partitioning of biomass was unaffected by N treatment but showed contrasting patterns between cultivars. The oilseed cultivar produced 30–42% more reproductive biomass and 18–30% less stem biomass than its textile counterpart. Differences between cultivars in these traits increased with increasing N rate. Maximum growth rates per plant concentrated around 1572°Cd after sowing (fructification). Faster leaf senescence after flowering contributed to the lower leaf area and leaf biomass of the textile cultivar.

The availability of N at different specific moments of the plant cycle would be useful to improve the growth of organs of economic interest. Results can also provide useful information to future nutrition models and breeding programs in textile and oilseed flax.

Keywords:

• Biomass accumulation
• leaf area
• Linum usitatissimum L.
• nitrogen supply
• partitioning

Acknowledgments

The authors thank Adriana Kantolic and Victor O. Sadras for their help in improving the manuscript and Jean Paul Trouve for the Diane cultivar seeds. This work was supported by University of Buenos Aires, Argentina (UBACyT program).