Can Chlorophyll a Fluorescence and Photobleaching Be a Stress Signal under Abiotic Stress in IVigna unguiculata/I L.?

• Published in: Sustainability 2022-11, Vol.14 (23)
• Main Authors: Pompelli, Marcelo F, Arrieta, Daniela Vegliante, Rodríguez, Yirlis Yadeth Pineda, Ramírez, Ana Melisa Jiménez, Bettin, Ana Milena Vasquez, Avilez, María Angélica Quiñones, Cárcamo, Jesús Adolfo Ayala, Garcia-Castaño, Samuel Giovanny, González, Lina María Mestra, Cordero, Elias David Florez, Montaño, Marvin José Perneth, Mendoza, Cristian Camilo Pacheco, González, Anthony Ricardo Ariza, Coley, Alberto José Tello, Jarma-Orozco, Alfredo, Rodriguez Paez, Luis Alfonso
• Format: Article
• Language: English
• Subjects: Agricultural research; Chlorophyll; Cowpea; Environmental aspects; Fluorescence; Growth (Plants); Psychological aspects
• ISSN: 2071-1050; 2071-1050
• DOI: 10.3390/su142315503

Greenhouse gas emissions continue raising the planet’s temperature by 1.5 °C since the industrial age, while the world population growth rate is 1.1%. So, studies aimed at food security and better land use are welcomed. In this paradigm, we choose Vigna unguiculata to test how it would behave in the face of severe abiotic stresses, such as drought and salt stress. This study shows that under abiotic stresses V. unguiculata tries to overcome the stress by emitting chlorophyll a fluorescence and promoting photobleaching. Thus, fewer photons are directed to photosystem I, to generate lethal reactive oxygen species. The antioxidant system showed a high activity in plants submitted to drought stress but fell in salt-stressed plants. Thus, the reductor power not dissipated by fluorescence or heat was captured and converted into hydrogen peroxide (H[sub.2] O[sub.2] ) which was 2.2-fold higher in salt-stressed V. unguiculata plants. Consequently, the malondialdehyde (MDA) increased in all treatment. Compiling all data, we can argue that the rapid extinguishing of chlorophyll a fluorescence, mainly in non-photochemical quenching and heat can be an indicator of stress as a first defense system, while the H[sub.2] O[sub.2] and MDA accumulation would be considered biochemical signals for plant defenses or plant injuries.