Science Briefs

Researchers seek to make a better Fuji apple

Fuji apples have become increasingly popular, but the apple variety faces some challenges on its path to full consumer appreciation: The poor and inconsistent peel color of Fuji apple strains has limited the apple’s marketability. The authors of a new study say that the introduction of new Fuji strains could increase the apple’s approval.

Esmaeil Fallahi, Bahar Fallahi, and Bahman Shafii from the University of Idaho and Zabihollah Zamani from the University of Tehran published the results of their six-year study in HortScience. The team studied the long-term effects of five Fuji strains (Autumn Rose, Desert Rose, Myra, September Wonder and Top Export on RN 29 rootstock) on fruit yield and harvest time quality.

They found that apples from September Wonder Fuji trees were larger than those of other strains in five of the six years that the experiments took place. September Wonder fruit was less firm than the other strains but showed a higher starch degradation pattern every year, traits the researchers attributed to the strain’s earlier maturity. American Society for Horticultural Science

Glacier-melt rich in bioavailable iron

A newly discovered source of oceanic bioavailable iron could have a major impact on our understanding of marine food chains and global warming. A British team has discovered that summer meltwaters from ice sheets are rich in iron, which will have important implications on phytoplankton growth. The findings are reported in the journal Nature Communications.

It is well known that bioavailable iron boosts phytoplankton growth in many oceans. In turn, phytoplankton capture carbon – thus buffering the effects of global warming. The plankton also feed into the bottom of the oceanic food chain, providing a food source for marine animals.

The researchers from the Universities of Bristol, Leeds and Edinburgh and the National Oceanography Centre collected meltwater discharged from the Leverett Glacier in Greenland over the summer of 2012. It was subsequently tested for bioavailable iron content. The researchers found that the water exiting from beneath the melting ice sheet contained significant quantities of previously unconsidered bioavailable iron. This means polar oceans receive a seasonal iron boost as the glaciers melt. European Association of Geochemistry

How the octopus avoids tangled tentacles

An octopus’s arms are covered in hundreds of suckers that will stick to just about anything – with one important exception: Those suckers generally won’t grab the octopus itself, otherwise the impressively flexible animals would quickly find themselves all tangled up.

Researchers from the Hebrew University of Jerusalem report they discovered how octopuses manage this feat, even as the creatures’ brains are unaware of what their tentacles are doing. A chemical produced by octopus skin temporarily prevents their suckers from sucking.

“The results so far show, and for the first time, that the skin of the octopus prevents octopus arms from attaching to each other or to themselves in a reflexive manner,” the researchers write.

“The drastic reduction in the response to the skin crude extract suggests that a specific chemical signal in the skin mediates the inhibition of sucker grabbing.”

The researchers haven’t yet identified the active agent in the animals’ self-avoidance behavior, but say it is yet another demonstration of octopus intelligence. The self-avoidance strategy might even find its way into bio-inspired robot design.

The research was published this month in Current Biology.