Explaining why pruning encourages plants to thriveSeptember 22, 2009Scientists have shown that the main shoot dominates a plant's growth principally because it was there first, rather than due to its position at the top of the plant. Collaborating teams from the University of York in the UK and the University of Calgary in Canada combined their expertise in molecular genetics and computational modelling to make a significant discovery that helps explain why pruning encourages plants to thrive. Understanding of the action and interaction of these hormones can inform horticultural practices aimed at changing branching patterns in diverse crops. The research was funded by the Biotechnology and Biological Sciences Research Council (BBSRC) and the Natural Sciences and Engineering Research Council of Canada (NSERC). Led by Professors Ottoline Leyser and Przemyslaw Prusinkiewicz and published by the journal PNAS, the research showed that all shoot tips on a plant can influence each other's growth. Professor Leyser, of the University of York's Department of Biology, said: "It is well known that the main growing shoot of a plant can inhibit the growth of the shoots below - that's why we prune to encourage growth of branches. What we are interested in is exactly how the main shoot can exert this effect. "It has been known since the 1930s that the plant hormone auxin is released by the plant's actively growing tip and is transported down the main stem where it has an indirect effect on buds to inhibit branching. There are a number of ways in which the hormone exerts this effect and we have discovered a new path by which it works." The research suggests that for a shoot tip to be active, it must be able to export auxin into the main stem. But if substantial amounts of auxin already exist in the main stem, export from an additional shoot tip cannot be established. Professor Leyser said: "Using this mechanism, all the shoot tips on a plant compete with each other, so that tips both above and below can influence each other's growth. This allows the strongest branches to grow the most vigorously, wherever they may be on the plant. The main shoot dominates mostly because it was there first, rather than because of its position at the apex of the plant." The teams went on to show that the recently discovered plant hormone, strigolactone, works at least in part by making it harder to establish new auxin transport pathways from shoot tips, strengthening the competition between auxin sources and reducing branching. The research also involved scientists at the Department of Forest Genetics and Plant Physiology at the Swedish University of Agricultural Sciences. University of York |
|||||||||||||||||||||
| Related Pruning Current Events and Pruning News Articles Sun or shade: Pecan leaves' photosynthetic light response evaluated Pecan, the most valuable nut tree native to North America, is native from northern Illinois and southeastern Iowa to the Gulf Coast of the United States, where it grows abundantly along the Mississippi River, the rivers of central and eastern Oklahoma, and Texas. Study of alternate bearing presents recommendations for citrus growers Alternate bearing (also called biennial or uneven bearing) is the tendency of fruit trees to produce a heavy crop one year (called "on-crop") followed by a light crop or no crop the following "off-crop" year. Tiny but adaptable wasp brains show ability to alter their architecture For an animal that has a brain about the size of two grains of sand, a lot of plasticity seems to be packed into the head of the tropical paper wasp Polybia aequatorialis. Getting wired: how the brain does it In a new study, researchers at the Montreal Neurological Institute and Hospital (The Neuro), McGill University have found an important mechanism involved in setting up the vast communications network of connections in the brain. New insights into growth factor's role in brain development New research sheds light on a neural growth factor called proBDNF, finding that it is present and potentially active during the perinatal period when the brain's circuitry and memory-encoding regions are being refined. Tequila boom triggers social, environmental hangover in Mexico New North Carolina State University research shows that tequila's surge in popularity over the past 15 years has been a boon for industry, but is triggering a significant hangover of social and environmental problems in the region of Mexico where the once-notorious liquor is produced. Flowering plants speed post-surgery recovery Contact with nature has long been suspected to increase positive feelings, reduce stress, and provide distraction from the pain associated with recovery from surgery. Now, research has confirmed the beneficial effects of plants and flowers for patients recovering from abdominal surgery. New studies suggest brain overgrowth in 1-year-olds linked to development of autism Brain overgrowth in the latter part of an infant's first year may contribute to the onset of autistic characteristics, according to research presented today at the American College of Neuropsychopharmacology (ACNP) annual meeting. These findings support concurrent research which has found brain overgrowth in autistic children as young as two years old. Autism-related proteins control nerve excitability, researchers find Two proteins that are implicated in autism have been found to control the strength and balance of nerve-cell connections, researchers at UT Southwestern Medical Center have found. Prefrontal cortex loses neurons during adolescence, researchers find Researchers at the University of Illinois have found that adolescence is a time of remodeling in the prefrontal cortex, a brain structure dedicated to higher functions such as planning and social behaviors. More Pruning Current Events and Pruning News Articles |
|||||||||||||||||||||
|
|||||||||||||||||||||
|
|||||||||||||||||||||