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Hulatt, C. J.

Publications and source records attributed to Hulatt, C. J..

2 recordsLinked to original sources

Experimental breeding reveals mating patterns and F1 phenotypic diversification in the cosmopolitan diatom Cylindrotheca

Diatom mating activity contributes to their enormous phenotypic and genetic diversity, yet little is known about patterns in diatom reproductive compatibility across genetically diverse strains, nor the effects on offspring phenotypes that may confer adaptive evolution, niche partitioning, or trait improvement. Here a panel of 38 Arctic Cylindrotheca sp. isolates were crossed pairwise to detect mating compatibility. Positive mating patterns were identified in multiple clades, including amongst crosses of different parental rbcL genotypes. F1 isolated from three different crosses presented phenotypic variation in growth rate, plastid traits, and associated photo-physiological responses to blue and green actinic light. Offspring gliding speed and behaviour also varied, providing insights into complex motility traits that link cell morphology, bioenergetics and sensory adaptation with emergent movement patterns. Exploratory analysis of the F1 trait landscape identified a varaible mixture of individual-level and cross-dependent effects, including substantial variation in growth rate between individuals and strong effects of different crosses on morphology and motility. Experimental diatom breeding may offer a unique strategy to study ocean protist evolution and phenotypic diversification and could complement other biotechnological innovations to enhance cultivation yields and crop resilience in mass cultivation.

microbiology↗

Microbial community dynamics during a harmful Chrysochromulina leadbeateri bloom

A harmful algae bloom occurred in late spring 2019 across multiple, interconnected fjords and bays in northern Norway. The event was caused by the haptophyte Chrysochromulina leadbeateri and led to severe fish mortality at several salmon aquaculture facilities. This study reports on the spatial and temporal succession dynamics of the holistic marine microbiome associated with this bloom by relating all detectable 18S and 16S rRNA gene ASVs to the relative abundance of the C. leadbeateri focal taxon. A k-medoids clustering enabled inferences on how the causative focal taxon co-bloomed with diverse groups of bacteria and microeukaryotes. These co-blooming patterns showed high temporal variability and were distinct between two geographically separated time series stations during the regional harmful algae bloom. The distinct blooming patterns observed with respect to each station were poorly connected to environmental conditions suggesting that other factors, such as biological interactions, may be at least as important in shaping the dynamics of this type of harmful algae bloom. A deeper understanding of microbiome succession patterns during these rare but destructive events will help guide future efforts to forecast deviations from the natural bloom cycles of the northern Norwegian coastal marine ecosystems that are home to intensive aquaculture activities.

microbiology↗