And the top five most popular tweets of 2021 at HowPlantsWork are:
“So how do plants prevent elongated growth under deep shade conditions? The secret lies in their internal clocks, says the research collaboration from the John Innes Centre and the University of Bristol.
They have discovered that when plants detect deep shade, this changes the expression of genes in certain parts of the circadian clock – the internal daily timer found in plants and other organisms. These clock components perform an additional role in suppressing stem elongation, blocking the over-topping of neighbours that would normally happen in moderate shade.”
“While sunflowers are growing, their heads turn back and forth to track the sun during the day.”
“But as the flower heads, or capitula, mature and their stems become stiff and woody, this movement decreases until the heads are all facing the morning sun.”
“Sunflowers face the rising sun because increased morning warmth attracts more bees and also helps the plants reproduce more efficiently, according to a study by researchers at the University of California, Davis.”
“Monks once hoped to turn lead into gold through alchemy. But consider the cauliflower instead. It takes just two genes to transform the ordinary stems, stalks and flowers of the weedy, tasteless species Brassica oleracea into a formation as marvelous as this fractal, cloudlike vegetable.”
Recent research published here, “...suggest the fractals form in response to shifts in the networks of genes that govern floral development.”
“The order of the florets in a flower head is not random. Instead, they are patterned into regular spirals whose number follows the Fibonacci sequence familiar from mathematics. Fibonacci numbers are the sum of the two preceding numbers in the sequence: 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144…
In the flower head, the number of left- and right-winding spirals is always two consecutive Fibonacci numbers. Sunflower flower heads can have as many as 89 right-winding and 144-left winding spirals, while the gerbera, another much-studied plant from the Asteraceae plant family, has fewer spirals (34/55).”
“Now, for the first time, the researchers have been able to examine on the molecular level how floral primordia are patterned into spirals in the growing point, or the meristem, of gerberas. They have had available to them a technical solution whose utilisation in plant science could only be dreamed of a couple of decades ago.”
“When it comes to parasites, these plants are the stuff of nightmares.
Called Rafflesiaceae, they have no roots, stems, or leaves of their own. For most of their lifespan they are invisible, living only as a small necklace of cells inside the woody vines of their host. Then, without warning — like the creature in the movie “Alien” — they burst out to bloom some of the largest flowers in the world. Their pungent smell of rotting meat or fruit attracts the carrion flies that help pollinate these plants, allowing them to seed and spread to another unsuspecting host, restarting the whole cycle.”
“On Jan. 22 in Current Biology, a team of Harvard-led researchers presented the most complete genome yet assembled of one of the major Rafflesiaceae lineages, Sapria himalayana.”