Enhancement of root growth and nitrogen fixation in Trigonella by UV-exclusion from solar radiation

• Published in: Plant physiology and biochemistry 2012-12, Vol.61, p.97-102
• Main Authors: Sharma, Sonika, Guruprasad, K.N.
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Biomass; cages; Exclusion; fertilizers; field experimentation; filters; Fundamental and applied biological sciences. Psychology; Growth; Heme - metabolism; leghemoglobin; Leghemoglobin - metabolism; Nitrogen - metabolism; Nitrogen fixation; Nitrogen Fixation - physiology; nitrogenase; Nitrogenase - metabolism; Plant physiology and development; Plant Proteins - metabolism; Plant Roots - growth & development; Plant Roots - metabolism; Plant Roots - physiology; root growth; solar radiation; Sunlight; Trigonella - growth & development; Trigonella - metabolism; Trigonella - physiology; Trigonella foenum-graecum; ultraviolet radiation; Ultraviolet Rays; UV-A + B radiation; UV-B radiation
• ISSN: 0981-9428; 1873-2690
• DOI: 10.1016/j.plaphy.2012.10.003

A field experiment was conducted to study the impact of solar UV on root growth and nitrogen fixation in Trigonella foenum-graecum. Plants were grown in iron mesh cages covered with polyester filters that could specifically cut off UV-B (280–315 nm) or UV-A + B (280–400 nm) part of the solar spectrum. The control plants were grown under a polythene filter transmissible to UV. Root biomass, number of nodules and nodule fresh weight were enhanced after exclusion of solar UV. Nitrogenase activity was significantly enhanced by 120% and 80% in the UV-B and UV-A + B excluded plants respectively. Along with nitrogenase there was concomitant increase in leghemoglobin and hemechrome content in the nodules after exclusion of solar UV. These components of sunlight limits nitrogen fixation and their elimination can enhance nitrogen fixation with agricultural advantages like reduction in the use of fertilizers. ► Exclusion of solar UV-B and UV-A + B enhanced root biomass and nodulation in Trigonella foenum-graecum. ► By exclusion of solar UV nitrogenase activity in the nodules was significantly enhanced. ► Elimination of UV components from sunlight is beneficial to agriculture in terms of nitrogen fixation.