Effect of Emamectin Benzoate and Mancozeb Exposure, Singly and in Combination, on the Growth, Physiological, Enzymatic Activity, and Antioxidant Activity Characteristics of Green Beans ( <i>Phaseolus vulgaris</i> L.)

Emamectin benzoate (EM) and mancozeb (MZ) are frequently applied together in vegetable protection, but their combined biochemical effects on crops are not fully understood. The objective of this study was to evaluate the single and combined effects of EM and MZ on morphological, physiological, and metabolic changes such as growth parameters, photosynthetic parameters, oxidative damage, and antioxidant enzyme activity of Phaseolus vulgaris L. after applying pesticide. Two‐way factorial ANOVA showed significant main effects of both pesticides and highly significant interaction terms for most parameters, indicating pronounced nonadditive responses. The EM + MZ treatment markedly altered chlorophyll content and primary metabolites, strongly increased protein, phenolic, and flavonoid levels, and induced pronounced changes in catalase (CAT), guaiacol peroxidase (GPOX), and polyphenol oxidase (PPO) activities. Antioxidant capacities (DPPH, 2,2‐diphenyl‐1‐picrylhydrazyl; ABTS, 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid), acid phosphatase (AP) activity, proline, thiobarbituric acid–reactive substances (TBARSs), and hydrogen peroxide (H 2 O 2 )) also showed synergistic EM × MZ interactions, revealing a substantial reconfiguration of the enzymatic and nonenzymatic antioxidant network. These results demonstrate that the EM + MZ mixture elicits more complex and intense biochemical adjustments than single‐pesticide treatments, profoundly reshaping redox homeostasis in green bean fruits.