Review on Cyanobacterial Studies in Portugal: Current Impacts and Research Needs

Abstract

Cyanobacteria have long been associated with harmful effects on humans, animals and aquatic biota. Cyanotoxins are their most toxic metabolite. This review summarizes the current research, impacts and future needs in cyanobacterial studies undertaken in Portugal, the southernmost country of Europe, and with a recent multiplication of cyanotoxicity due to climate change events. Microcystins are still the most prevalent, studied and the only regulated cyanotoxins in Portuguese freshwater systems much like most European countries. With the development of some tools, particularly in molecular studies, the recent discovery of cylindrospermopsins, anatoxins and saxitoxins, both genes and toxins, in North and Center ecosystems of our country highlight current impacts that overall communities are facing with increased risks of exposure and uptake to cyanotoxins. Research needs encompass the expansion of studies at all aspects due to the uprising of these cyanotoxins and reinforces the urgent need of increasing the frequency of surveillance to achieve tangible effects of cyanotoxins in Portugal to ultimately implement regulations on cylindrospermopsins, anatoxins and saxitoxins worldwide.

Phytostimulants in sustainable agriculture

“…Studies have reported drought and salinity stress mitigation via the use of dual combination of AMF and PGPR. Maximum increase in biomass, ion, and nutrient content in maize was exhibited by plants under salinity stress, treated with combination of AMF (Rhizoglomus irregulare) and PGPR (Pseudomonas reactans and Pantoea alli) (Moreira et al, 2021). In another study by Kamali and Mehraban (2020), Azotobacter and Azospirillum (PGPR) in combination with Glomus mosseae (AMF) resulted in significant amelioration of drought stress in sorghum as indicated by enhanced antioxidant enzymes (CAT, POD, and APX), total carotenoid, anthocyanin, and flavonoid contents.…”

“…Apart from its importance, there are some constraints to the use of cyanobacteria, as they secrete some toxins like cylindrospermopsin, anatoxin, and saxitoxin in fresh water with harmful effects on humans, animals, and aquatic biota (Moreira et al, 2021). Therefore, some mechanical, that is, artificial mixing, hypolimnetic aeration, dredging, and sonication and biological (biomanipulation, macrophytes, and straws), methods should be employed to manage cyanobacterial bloom (Kibuye et al, 2021).…”