Trends in Biosensors and Current Detection Methods for Stress Monitoring of Plants Growing in Adverse Environmental Conditions

Plant growth and development are negatively affected by a wide range of external adverse conditions, such as water stress, nutrient deficiency, and pathogens. In the near future, these constraints are expected to grow in importance if the climate change predicted comes about. Low-cost and quick detection of abiotic stresses due to harsh environmental conditions are key factors for the reduction of losses in crop yield. The current detection methods like polymerase chain reaction, enzyme-linked immunosorbent assays, and gas chromatography–mass spectrometry have a wide range of applications but are expensive, time-consuming, labor-intensive, and require detailed data sampling and processing. Thus, novel techniques like optical and electrochemical biosensors with advantages such as ease of use, portability, high sensitivity, and low cost have also been fabricated. A biosensor is defined as an analytical device that integrates a biologically active material with a transducer for the qualitative and quantitative sensing of chemical or biochemical phenomena occurring at the sensor’s surface by the conversion of a biological recognition response into an electrical signal, which is further processed in order to be represented as output display. In view of this, the chapter reviews the biosensors that have been recently developed for the detection of stress biomarkers of plants growing in resilient environments. In addition, the chapter also lays emphasis on highly selective bio-recognition elements such as enzyme, antibody, DNA/RNA, and bacteriophages. Finally, have also highlighted the biosensors regarding volatile organic compounds emitted from leaves prime plant’s defense mechanisms for an enhanced resistance/tolerance to the upcoming stress.