Volatile organic compound profiling of Capsicum annuum var. longum grown under different concentrations of nitrogen

Emission of volatile organic compounds (VOCs) in plants is triggered by several biotic and abiotic factors, such as nutrient deficiency, environmental stress, and pathogenic attacks. For instance, plants suffering from limited or excessive nitrogen (N) supply may experience internal stress which can ultimately lower their stability and immunity making them susceptible to infection and infestation. In this study, VOCs from Capsicum annuum var. longum (Solanaceae) exposed to nitrogen (1.8 g/L, 4.5 g/L, and 9 g/L urea) were extracted using a 100 μm Solid Phase Microextraction (SPME) fiber coated with polydimethylsiloxane (PDMS). Using Gas Chromatography-Mass Spectrometry (GC-MS), extracted VOCs from N-treated plants were identified as Butanoic acid, 3-hexenyl ester, (E)-; Butanoic acid, hexyl ester; Hexanoic acid, 3-hexenyl ester, (Z)-; Hexanoic acid, 4-hexen-1-yl ester; cis-3-Hexenyl cis-3-hexenoate and 4-Pentenoic acid 2-methyl-, hexyl ester. Among these volatiles, butanoic acid, 3-hexenyl ester showed the most distinctive peak from the N-treated plants in comparison with the untreated. In addition, the Green Leaf Volatiles (GLV) 3-Hexenal; 2-Hexenal; 3-Hexen-1-ol, (Z)-; 2-Hexen-1-ol, (E) and 1-Hexanol were also detected from the N-treated plants. The identification of plant volatiles provides useful information that can be used in agricultural practices and plant phenotyping.