Positive effects of nitric oxide on Solanum lycopersicum

Abstract

The present work examines benzoic acid (BA) induced stress in Solanum lycopersicum and explores the possible mechanism through which sodium nitroprusside (SNP) protects plants. Tomato seeds were soaked for 3 h in 250 µM SNP and 0.5, 1.0, and 1.5 mM BA with and without SNP. Seeds soaked in distilled water were treated as control. Seed germination (SG) and radicle length (RL) were recorded in Petri plate culture. SG and RL inhibition was concentration dependent in BA. SNP enhanced SG and RL. Twenty-one-days old seedlings were grown in hydroponic culture in Hoagland solution and BA at 0.5, 1.0, and 1.5 mM with and without SNP. The morphological and biochemical parameters of seedlings were assayed. Average growth rate of root and shoot, dry weight, sugar, pigment and protein content, and activity of nitrate reductase decreased in seedlings treated with BA while increased in SNP with and without BA. Lipid peroxidation increased in seedlings treated with BA but decreased in BA+SNP. SNP protected the seedlings against BA induced oxidative stress by scavenging reactive oxygen species. SNP demonstrated a positive role against BA toxicity which was evident from increased activities of antioxidant enzymes.

Keywords:

• allelopathy
• antioxidant enzymes
• benzoic acid
• lipid peroxidation
• nitric oxide
• sodium nitroprusside

Acknowledgments

The authors are thankful to the University Grant Commission, New Delhi, and University of Allahabad for providing financial assistance to Kavita Yadav.