Unlocking pest detection and monitoring in greenhouse tomato agriculture: Harnessing eDNA technology

Arthropod pests pose a significant threat to controlled environment agriculture, particularly in greenhouses, where early detection is challenging due to their cryptic behavior and small size. Environmental DNA (eDNA) emerges as a powerful tool for detecting these elusive and destructive pests. This is achievable because eDNA detects the genetic material shed by organisms into their surroundings. Extraction from various environmental samples enables detection without relying on visual aids or physical trapping. Our primary objective was to employ eDNA to detect sweet potato whiteflies (Bemisia tabaci), green peach aphids (Myzus persicae), and two-spotted spider mites (Tetranychus urticae) in greenhouse-grown tomato plants. Our secondary objective was to design specific DNA primers for each pest. We hypothesized that greenhouses would provide a conducive environment for eDNA detection, given limited exposure to external factors that could hinder detection. To test our hypothesis, we employed polymerase chain reaction (PCR) and real-time quantitative PCR (qPCR) to identify the presence of the target pests on tomato plant leaves. DNA amplification through conventional PCR and qPCR, utilizing species-specific primers, facilitated positive detection without off-target amplification. Sensitivity assays demonstrated the efficacy of eDNA amplification even at low population densities, detecting the genetic material of a single B. tabaci individual on a tomato plant leaf. In conclusion, our study underscores the efficacy of eDNA in controlled environment agriculture for detecting genetic material from distinct pest species. These findings highlight the potential of eDNA in greenhouses, offering growers an accurate and sensitive means of pest detection without relying on visual identification.