Retirement age for faculty members

DLSU Administration and AFED has signed the agreement to move retirement age of faculty members to 65

Sensitivity of Antarctic Urospora penicilliformis (Ulotrichales, Chlorophyta) to ultraviolet radiation is life stage dependent

The sensitivity of different life stages of the eulittoral green alga Urospora penicilliformis (Roth) Aresch. to ultraviolet radiation (UVR) was examinedin the laboratory. Gametophytic filaments and propagules (zoospores and gametes) released from filaments were separately exposed to different fluence of radiation treatments consisting of PAR (P = 400700 nm), PAR + ultraviolet A (UVA) (PA, UVA = 320400 nm), and PAR + UVA + ultraviolet B (UVB) (PAB, UVB = 280320 nm). Photophysiological indices (ETRmax, Ek, and a) derived from rapid light curves were measured in controls, while photosynthetic efficiency and amount of DNA lesions in terms of cyclobutane pyrimidine dimers (CPDs) were measured after exposure to radiation treatments and after recovery in low PAR; pigments of propagules were quantified after exposure treatment only. The photosynthetic conversion efficiency (a) and photosynthetic capacity (rETRmax) were higher in gametophytes compared with the propagules. The propagules were slightly more sensitive to UVB-induced DNA damage; however, both life stages of the eulittoral inhabiting turf alga were not severely affected by the negative impacts of UVR. Exposure to a maximum of 8 h UVR caused mild effects on the photochemical efficiency of PSII and induced minimal DNA lesions in both the gametophytes and propagules. Pigment concentrations were not significantly different between PAR-exposed and PAR + UVRexposed propagules. Our data showed that U. penicilliformis from the Antarctic is ratherinsensitive to the applied UVR. This amphi-equatorial species possesses different protective mechanisms that can cope with high UVR in coldtemperatewaters of both hemispheres and in polar regions under conditions of increasing UVR as a consequence of further reduction of stratosphericozone

Seaweed - a resource for organic farming

Traditionally, coastal communities worldwide have been using drift seaweed as soil amendment. The fertilizing effect of composted seaweed is dependent on their biochemical composition, mineralization pattern and the synchronization of nutrients with the crops' demand. Seaweed is commercially available, and considered as a resource for organic farming

Editorial: Opening the black box of kelps: Response of early life stages to anthropogenic stressors

Kelps form marine forests along world’s coastlines, providing valuable ecosystem goods and services, either directly as a source offood or medicinal products, or indirectly as biogenic habitats or carbon sink agents (Teagle et al., 2017; Wernberg et al., 2019). However, kelp forests are currently under threat due to anthropogenic climate change with latitudinal range shifts and large-scale declines at a global scale (Smale et al., 2019; Wernberg et al., 2019). Most studies on the impact of anthropogenic stressors on kelps have focused on the macroscopic sporophyte stage of the haploid-diploid life cycle (Schiel and Foster, 2006; Veenhof et al., 2022). However, the microscopic stages considered as the “black box” of kelps due to the complexity of studying them in situ, have been suggested to play a crucial role in the persistence of populations that experience sporophyte mortality after large-scale disturbances (McConnico and Foster, 2005; Barradas et al., 2011) as they can persist as “seed bank” analogues under adverse conditions (Hoffmann and Santelices, 1991; Veenhof et al., 2022). This Research Topic is a collection of 8 articles contributing to opening the “black box” of kelps by providing greater insight into how microscopic life stages of kelps are affected by anthropogenic climate change, helping to predict the persistence of these foundation species and therefore the fate of ecosystems and coastal communities. These studies highlight that the response of kelp early life stages to stressors can be strongly dependent on the population and thermal history.Australian Research Council DP190100058, DP200100201info:eu-repo/semantics/publishedVersio

Towards a Flexible Learning Ecosystem in Philippine Tertiary Education

The Philippines has responded to the COVID-19 pandemic by implementing a lockdown in an effort to suppress the spread of the disease. This measure has led to unprecedented disruption in many sectors of the economy. Educational institutions have similarly been affected. As schools are the ideal breeding ground for “super spreader” events, the suspension of face-to-face instruction is an important control measure from a public health perspective. Physical closures may need to be maintained even after the lockdown is eased. This situation poses a challenge on how to maintain the continuity of the Philippines’ human capital development during the pandemic

Microscopic life stages of North Atlantic Laminaria digitata (Phaeophyceae) exhibit trait-depedent thermal adaptation along latitudes

Kelp forests in the North Atlantic are at risk of decline at their warm temperature distribution margins due to anthropogenic temperature rise and more frequent marine heat waves. To investigate the thermal adaptation of the cold-temperate kelp Laminaria digitata, we sampled six populations, from the Arctic to Brittany (Spitsbergen, Tromsø, Bodø [all Norway], Helgoland [Germany], Roscoff and Quiberon [both France]), across the species’ entire distribution range, spanning 31.5° latitude and 12-13°C difference in mean summer sea surface temperature. We used pooled vegetative gametophytes derived from several sporophytes to approximate the genetic diversity of each location. Gametophytes were exposed to (sub-) lethal high (20-25°C) and (sub-) optimal low (0-15°C) temperature gradients in two full-factorial, common-garden experiments, subjecting subsets of populations from different origins to the same conditions. We assessed survival of gametophytes, their ability to develop microscopic sporophytes, and subsequent growth. We hypothesized that the thermal performance of gametophytes and microscopic sporophytes corresponds to their local long-term thermal history. Integrated gametophyte survival revealed a uniform upper survival temperature (UST) of 24°C among five tested populations (Tromsø to Quiberon). In contrast, following two weeks of thermal priming of gametophytes at 20-22°C, sporophyte formation at 15°C was significantly higher in southern populations (Quiberon and Roscoff) compared to the high-latitude population of Tromsø. Between 0-15°C, survival of the Arctic population (Spitsbergen) was negatively correlated with increasing temperatures, while the southernmost population (Quiberon) showed the opposite. Thus, responses of survival at low, and sporophyte formation at high temperatures, support the concept of local adaption. On the other hand, sporophyte formation between 0-15°C peaked at 6-9°C in the Quiberon and at 9-12°C in the Spitsbergen population. Sporophyte growth rates (GR) both in length and width were similar for Spitsbergen, Tromsø and Quiberon; all had maximum GRs at 12-15°C and low GRs at 0-6°C. Therefore, responses of sporophyte formation and growth at low temperatures do not reflect ecotypic adaptation. We conclude that L. digitata populations display trait-dependent adaptation, partly corresponding to their local temperature histories and partly manifesting uniform or unpredictable responses. This suggests differential selection pressures on the ontogenetic development of kelps such as L. digitata

Seaweed reproductive biology: environmental and genetic controls

Knowledge of life cycle progression and reproduction of seaweeds transcends pure academic interest. Successful and sustainable seaweed exploitation and domestication will indeed require excellent control of the factors controlling growth and reproduction. The relative dominance of the ploidy-phases and their respective morphologies, however, display tremendous diversity. Consequently, the ecological and endogenous factors controlling life cycles are likely to be equally varied. A vast number of research papers addressing theoretical, ecological and physiological aspects of reproduction have been published over the years. Here, we review the current knowledge on reproductive strategies, trade-offs of reproductive effort in natural populations, and the environmental and endogenous factors controlling reproduction. Given that the majority of ecophysiological studies predate the "-omics" era, we examine the extent to which this knowledge of reproduction has been, or can be, applied to further our knowledge of life cycle control in seaweeds.European Commission [FA1406]; China Scholarship Council [201504910698]; Ghent University BOF Special Research Fund [01SC2316]; FCT fellowship [SFRH/BPD/107878/2015]info:eu-repo/semantics/publishedVersio

Iodine content in bulk biomass of wild-harvested and cultivated edible seaweeds: Inherent variations determine species-specific daily allowable consumption

This study represents a large-scale investigation into iodine contents in three commercially important and edible seaweed species from the North Atlantic: the brown algae Saccharina latissima and Alaria esculenta, and the red alga Palmaria palmata. Variability among and within species were explored in terms of temporal and spatial variations in addition to biomass source. Mean iodine concentration in bulk seaweed biomass was speciesspecific: Saccharina > Alaria > Palmaria. Iodine contents of Saccharina biomass were similar between years and seasons, but varied significantly between sampling locations and biomass sources. In Alaria and Palmaria, none of the independent variables examined contributed significantly to the small variations observed. Our data suggest that all three species are rich sources of iodine, and only 32, 283, or 2149 mg dry weight of unprocessed dry biomass of Saccharina, Alaria, or Palmaria, respectively, meets the recommended daily intake levels for most healthy humans.publishedVersio