Plastic debris is an established environmental menace affecting aquatic systems globally. Recently, microplastics (MP) and plastic leachates (PL) have been detected in vital human organs, the vascular system, and in vitro animal studies positing severe health hazards. MP and PL have been found in every conceivable aquatic ecosystem�from open oceans and deep sea floors to supposedly pristine glacier lakes and snow covered mountain catchment sites. Many studies have documented the MP and PL impacts on a variety of aquatic organisms, whereby some exclusively focus on aquatic microorganisms. Yet, the specific MP and PL impacts on primary producers have not been systematically analyzed. Therefore, this review focuses on the threats posed by MP, PL, and associated chemicals on phytoplankton, their comprehensive impacts at organismal, community, and ecosystem scales, and their endogenous amelioration. Studies on MP-and PL-impacted individual phytoplankton species reveal the production of reactive oxygen species, lipid peroxidation, physical damage of thylakoids, and other physiological and metabolic changes, followed by homo-and heteroaggregations, ultimately eventuating in decreased photosynthesis and primary productivity. Likewise, analyses of the microbial community in the plastisphere show a radically different profile compared to the surrounding planktonic diversity. The plastisphere also enriches multidrug-resistant bacteria, cyanotoxins, and pollutants, accelerating microbial succession, changing the microbiome, and thus, affecting phytoplankton diversity and evolution. These impacts on cellular and community scales manifest in changed ecosystem dynamics with widespread bottom-up and top-down effects on aquatic biodiversity and food web interactions. These adverse effects�through altered nutrient cycling�have "knock-on" impacts on biogeochemical cycles and greenhouse gases. Consequently, these impacts affect provisioning and regulating ecosystem services. Our citation network analyses (CNA) further demonstrate dire effects of MP and PL on all trophic levels, thereby unsettling ecosystem stability and services. CNA points to several emerging nodes indicating combined toxicity of MP, PL, and their associated hazards on phytoplankton. Taken together, our study shows that ecotoxicity of plastic particles and their leachates have placed primary producers and some aquatic ecosystems in peril.

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Gymnostachyum febrifugum Benth. is a small, scapigerous, rare and endemic medicinal herb indigenous to India belonging to the family Acanthaceae. This study reports an e cient protocol for high-frequency ower bud derived callus induction and shoot organogenesis in G. febrifugum. Flower buds at 7d before anthesis (dBA) were excised from the in orescence and cultured on MS medium supplemented with various concentrations of 2, 4-dichlorophenoxy acetic acid (2, 4-D; 0.5-2.0 mg/l) for callus induction. The optimum callus induction (78%) was obtained on MS medium supplemented with 1.5 mg/l 2, 4-D. The calli when subcultured on MS medium supplemented with different concentrations of thidiazuron (TDZ; 0.5-2.5 mg/l) or 6-benzylaminopurine BAP (0.5-2.5 mg/l) alone or in combination with 1naphthaleneacetic acid (NAA; 0.2-0.7 mg/l) induced shoots. The highest frequency (94%) and number of shoots (44.6 shoots/unit callus) were obtained on MS medium supplemented with 2.0 mg/l TDZ and 0.5 mg/l NAA. The optimum rooting frequency (95%) and number of roots (10.2) were observed on ½ MS medium supplemented with 3.0 mg/l indole-3-butyric acid (IBA). The rooted plantlets were acclimatized and transferred to soil with 94% success.

Gymnostachyum febrifugum Benth. is a small, scapigerous, rare and endemic medicinal herb indigenous to India belonging to the family Acanthaceae. This study reports an efficient protocol for high-frequency flower bud derived callus induction and shoot organogenesis in G. febrifugum. Flower buds at 7d before anthesis (dBA) were excised from the inflorescence and cultured on MS medium supplemented with various concentrations of 2, 4-dichlorophenoxy acetic acid (2, 4-D; 0.5-2.0 mg/l) for callus induction. The optimum callus induction (78%) was obtained on MS medium supplemented with 1.5 mg/l 2, 4-D. The calli when subcultured on MS medium supplemented with different concentrations of thidiazuron (TDZ; 0.5-2.5 mg/l) or 6-benzylaminopurine BAP (0.5-2.5 mg/l) alone or in combination with 1- naphthaleneacetic acid (NAA; 0.2-0.7 mg/l) induced shoots. The highest frequency (94%) and number of shoots (44.6 shoots/unit callus) were obtained on MS medium supplemented with 2.0 mg/l TDZ and 0.5 mg/l NAA. The optimum rooting frequency (95%) and number of roots (10.2) were observed on ½ MS medium supplemented with 3.0 mg/l indole-3- butyric acid (IBA). The rooted plantlets were acclimatized and transferred to soil with 94% success.