I
Iron_Lion
I heard about this a while back on the Discovery Channel and did a little google search on the subject and came back with some interesting results. I figured I would post up here to open up discussion on the subject.
Source: http://www.eurekalert.org/pub_releases/2009-11/mu-ppt111609.php
Plants prefer their kin, but crowd out competition when sharing a pot with strangers
Plants don't mind sharing space with their kin but when they're potted with strangers of the same species they start invigorating their leaves, a study by McMaster University reveals.
The research, which appears in the current issue of the American Journal of Botany, suggests non-kin plants will not only compete underground for soil nutrients, but will attempt to muscle out the competition above ground in the ongoing struggle for light.
It follows previous research from McMaster University which found that plants can recognize their kin through root systems and will compete more strongly for soil nutrients and water with non-sibling plants.
"This is the first study that shows plants are responding to kin at the above ground level," explains Guillermo Murphy, lead author of the study and a graduate student in the Department of Biology at McMaster University. "When they recognize their kin, they grow differently in shape, taller, with more branches and fewer resources into leaves, therefore allowing their siblings to access precious sunlight."
When researchers planted seedlings of a North American species of shade-loving Impatiens in the same pot, they reacted mildly with other offspring from the same mother plant. But when planted among non-kin of the same species, the plants shift extra resources into growing leaves.
"This supports previous research that plants are capable of complex social behaviour and will exhibit altruistic behaviour, giving their siblings a competitive edge in the wild," says Murphy.
In a previous study, led by Susan Dudley, associate professor of biology at McMaster, the Great Lakes sea rocket or Cakile edentula, which flourishes on beaches, showed altruistic behavior among its kin at the root level. When nearby strangers were detected, the sea rocket shifted resources to roots, fighting for precious water and soil nutrients.
This all makes sense on an ecological level, says Murphy. Sea rockets would have easy access to sunlight in its natural beach habitat and therefore, would struggle for nutrients underground. Conversely, Impatiens thrive in the shady woodlands, where moisture is plentiful, but sunlight is scarce.
The roots seem to tell siblings from strangers, he says, whether the change in behaviour is above or below ground. But simply placing them beside one another, in separate pots, did not produce the same results.
In the lab, researchers germinated the seeds from Impatiens collected in the field, to ensure they were properly grouped by sibling and non-siblings.
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McMaster University, one of four Canadian universities listed among the Top 100 universities in the world, is renowned for its innovation in both learning and discovery. It has a student population of 23,000, and more than 140,000 alumni in 128 countries.
Source: http://www.eurekalert.org/pub_releases/2009-11/mu-ppt111609.php
Source: http://windstar.org/uncategorized/plants-can-recognize-and-prefer-their-kin/Plants Can Recognize and Prefer Their Kin
HAMILTON, ONTARIO, CANADA–The apparently passive garden plant is not as easy-going as people assume, at least not with strangers. Researchers at McMaster University have found that plants become competitive when forced to share a pot with strangers of the same species, but they are more friendly when potted with their siblings.
“The ability to recognize and favor kin is common in animals, but this is the first time it has been shown in plants,” said Dr. Susan Dudley, associate professor of biology at McMaster University in Hamilton.”When plants share their pots, they get competitive and start growing more roots, which allows them to grab water and mineral nutrients before their neighbors get them,” Dudley explains.
Biologist Susan Dudley is the first to discover that plants recognize their kin. “It appears, though, that they only do this when sharing a pot with unrelated plants; when they share a pot with family they don’t increase their root growth,” the biologist says.
Because differences between groups of strangers and groups of siblings only occurred when they shared a pot, the root interactions may provide a cue for kin recognition. Though they lack cognition and memory, Dudley says the study shows plants are capable of complex social behaviors such as altruism towards relatives.
Like humans, says Dudley, the most interesting plant behaviors occur beneath the surface.
Dudley and her student, Amanda File, observed the behavior in sea rocket, Cakile edentula, a member of the mustard family native to beaches throughout North America, including the Great Lakes, where McMaster is located near Lake Ontario.
Sea Rocket
The American sea rocket grows on sandy beaches above the high tide line. The two biologists grew batches of sea rocket in pots of four, either with specimens from the same maternal family or from several different families.Those growing with strangers had a greater mass of roots after two months of growing than those sharing pots with siblings.
Gardeners might want to use this discovery to change their plant arrangements, placing siblings close to one another.
“Gardeners have known for a long time that some pairs of species get along better than others, and scientists are starting to catch up with why that happens,” says Dudley. “What I’ve found is that plants from the same mother may be more compatible with each other than with plants of the same species that had different mothers.
“The more we know about plants, the more complex their interactions seem to be, so it may be as hard to predict the outcome as when you mix different people at a party,” she joked.
How the plants learn which neighbor is a relative is still a mystery. Dudley speculates that a protein or chemical signal specific to each plant’s family might be secreted and detected by other roots nearby.
The study was supported by a grant from the Natural Sciences and Engineering Research Council of Canada. It appeared recently in the Royal Society journal “Biology Letters.”--ENS