RESUMEN
The excessive usage of veterinary antibiotics has raised significant concerns regarding their environmental hazard and agricultural impact when entering surface water and soil. Animal waste serves as a primary source of organic fertilizer for intensive large-scale agricultural cultivation, including the widely utilized medicinal and edible plant, Polygonatum cyrtonem. In this study, we employed a novel plant stress tissue culture technology to investigate the toxic effects of tetracycline hydrochloride (TCH) and sulfadiazine (SDZ) on P. cyrtonema. TCH and SDZ exhibited varying degrees of influence on plant growth, photosynthesis, and the reactive oxygen species (ROS) scavenging system. Flavonoid levels increased following exposure to TCH and SDZ. The biosynthesis and signaling pathways of the growth hormones auxin and gibberellic acid were suppressed by both antibiotics, while the salicylic acid-mediated plant stress response was specifically induced in the case of SDZ. Overall, the study unveiled both common and unique responses at physiological, biochemical, and molecular levels in P. cyrtonema following exposure to two distinct types of antibiotics, providing a foundational framework for comprehensively elucidating the precise toxic effects of antibiotics and the versatile adaptive mechanisms in plants.
Asunto(s)
Antibacterianos , Polygonatum , Antibacterianos/toxicidad , Fotosíntesis , Reguladores del Crecimiento de las Plantas , Polygonatum/química , Sulfadiazina , Tetraciclina , TranscriptomaRESUMEN
Exposure to organic ultraviolet (UV) filters has raised concerns due to their potential adverse effects on environments. However, their toxic mechanisms on plants remain elusive. In this study, using integrative physiological and transcriptomic approaches we investigated the physiological and molecular responses to three representative UV filters, namely oxybenzone (OBZ), avobenzone (AVB), and octinoxate (OMC), in an agricultural model plant tobacco. The exposure to UV filters disrupts the functionality of photosystem reaction centers and the light-harvesting apparatus. Concurrently, UV filters exert a suppressive effect on the expression of genes encoding Rubisco and Calvin-Benson cycle enzymes, resulting in a decreased efficiency of the Calvin-Benson cycle and consequently hampering the process of photosynthesis. Exposure to UV filters leads to significant generation of reactive oxygen species within tobacco leaves and downregulation of oxidoreductase activities. Moreover, UV filters promote abscisic acid (ABA) accumulation by inducing the expression of ABA biosynthesis genes whereas repress indole-3-acetic acid (IAA) biosynthesis gene expression, which induce leaf yellowing and slow plant growth. In summary, the organic UV filters exert toxic effects on tobacco growth by inhibiting chlorophyll synthesis, photosynthesis, and the Calvin-Benson cycle, while generating excessive reactive oxygen species. This study sheds light on the toxic and tolerance mechanisms of UV filters in agricultural crops.