Crafty plants time their defences
SMALL PRINT:FOR PLANTS, being rooted to the spot tends to restrict your options for getting away from creatures that want to have you for dinner. But new findings highlight a crafty strategy in Arabidopsis plants to ward off a species of caterpillar: they make defensive chemicals at the time when insects are likely to be munching.
The study used light cycles to “entrain” the internal clocks of Arabidopsis plants and cabbage looper caterpillars (Trichoplusia ni) that like to feast on them. Half of the plants were placed with caterpillars that were in synch on a day-night cycle. But the other part of the experiment mixed up the phases, so the caterpillar clocks were set to daytime mode during the hours that the plants were in night-time mode. After allowing the loopers to feed freely on the plants for 72 hours, the researchers assessed damage to the plants in the different groups.
“We found that the plants whose clocks were in phase with the insects were relatively resistant, whereas the plants whose clocks were out of phase were decimated by the insects feeding on them,” said researcher Danielle Goodspeed from Rice University in a release. The study also found that Arabidopsis increases production of a defensive chemical called jasmonate during the day, which is when the cabbage loopers tend to feed. “When you walk past plants, they dont look like they’re doing anything,” said Janet Braam, an investigator on the study, which was published online this week in the Proceedings of the National Academy of Sciences. “Its intriguing to see all of this activity down at the genetic level. Its like watching a besieged fortress go on full alert.”
Breakthrough to Lake Vostok
IT HAS BEEN a long time coming, but Russias Arctic and Antarctic Research Institute has confirmed that its drilling team has broken through to Lake Vostok, a sub-glacial lake in Antarctica.
“Penetration to relic water of subglacial Lake Vostok through the deep ice borehole 5G was performed by drillers of the glacial-drilling team of the 57th Russian Antarctic Expedition, it announced in a formal report released in English.
Attempts to reach the lake, which lies under ice that’s more than 3 kilometres thick, have been long drawn out, in part because technical challenges abound.
For one, Vostok in Antarctica is a chilly place to work in: in the 1980s a record-breaking temperature of -89.2 °C was recorded there.
Drilling can take place only at certain times of the year, and around this time last year the drill was thought to be coming tantalisingly close to the lake water under the ice but the team could not break through before the deadline for leaving the area.
But this year, on February 5th, they got to the lake, which is thought to have been under ice for millions of years.
“This fills my soul with joy,” said Valery Lukin, from the AARI, according to a BBC report. This will give us the possibility to biologically evaluate the evolution of living organisms . . . because those organisms spent a long time without contact with the atmosphere, without sunlight.