东海甲藻原甲藻和Veneficum是东海有害藻华的优势种。它们的化感作用对海洋浮游植物种群演替的作用是一个正在进行辩论的主题,特别是关于花朵的形成。目的:探讨黄芩对东海白杨的化感作用,对光合性能(包括PSII功能活性,光合电子传递链,能量通量,光合不同基因和光合性能)和光合损伤诱导的氧化应激(MDA,SOD,和CAT活动)。东海假单胞菌的生长在最初四天受到强烈抑制(1-6倍,CK/CP),但是从第八天开始,细胞在低滤液浓度下逐渐恢复活性。在最强抑制的第四天,化感物质降低了代表性光合性能参数PI和ΦPSII,破坏了光合作用的相关过程,并提高了东海毕赤酵母的MDA含量。同时,东海假单胞菌通过上调13个光合基因的表达来修复这些损伤,修改光合过程,并从第八天开始激活抗氧化酶的活性。总的来说,本研究对化感光合损伤进行了深入的概述,基因和光合作用之间的关系,以及光合作用引起的氧化损伤的原因。环境含义:作为典型的HAB物种,Veneficum与许多鱼类中毒事件有关,对水生生态系统和人类健康产生负面影响。Veneficum产生的化感物质可以通过干扰生存来提供竞争优势,竞争物种的繁殖和生长。本研究主要研究了龙舌兰化感物质对东海原花青素光合作用和光合基因的影响。掌握化感物质抑制微藻的机理,有助于更好地了解藻华演替过程,为有效防治有害藻华提供新的科学依据。
Dinoflagellates Prorocentrum donghaiense and Karlodinium veneficum are the dominant species of harmful algal blooms in the East China Sea. The role of their
allelopathy on the succession of marine phytoplankton populations is a subject of ongoing debate, particularly concerning the formation of blooms. To explore the
allelopathy of K. veneficum on P. donghaiense, an investigation was conducted into photosynthetic performance (including PSII functional activities, photosynthetic electron transport chain, energy flux, photosynthetic different genes and photosynthetic performance) and photosynthetic damage-induced oxidative stress (MDA, SOD, and CAT activity). The growth of P. donghaiense was strongly restrained during the initial four days (1-6 folds, CK/CP), but the cells gradually resumed activity at low filtrate concentrations from the eighth day. On the fourth day of the strongest inhibition, allelochemicals reduced representative photosynthetic performance parameters PI and ΦPSII, disrupted related processes of photosynthesis, and elevated the levels of MDA content in P. donghaiense. Simultaneously, P. donghaiense repairs these impairments by up-regulating the expression of 13 photosynthetic genes, modifying photosynthetic processes, and activating antioxidant enzyme activities from the eighth day onward. Overall, this study provides an in-depth overview of allelopathic photosynthetic damage, the relationship between genes and photosynthesis, and the causes of oxidative damage induced by photosynthesis. ENVIRONMENTAL IMPLICATIONS: As a typical HAB species, Karlodinium veneficum is associated with numerous fish poisoning events, which have negative impacts on aquatic ecosystems and human health. Allelochemicals produced by K. veneficum can provide a competitive advantage by interfering with the survival, reproduction and growth of competing species. This study primarily investigated the effects of K. veneficum allelochemicals on the photosynthesis and photosynthetic genes of Prorocentrum donghaiense. Grasping the mechanism of allelochemicals inhibiting microalgae is helpful to better understand the succession process of algal blooms and provide a new scientific basis for effective prevention and control of harmful algal blooms.