Why leaves fall off trees London (PTI): Ever wondered why leaves fall off trees in fall?
Well, the secret actually lies in cellular mechanism, says a new study. Researchers have found that trees use an elaborate cellular mechanism to part company from their leaves, which act as “solar cells” in the summer but become superfluous in the darker winter months. According to them, at the base of each leaf is a special layer called the abscission zone. When the time comes in autumn to shed a leaf, cells in this layer begin to swell, slowing the transport of nutrients between the tree and leaf. And, once the abscission zone has been blocked, a tear line forms and moves downwards, until eventually the leaf is blown away or falls off — a protective layer seals the wound thereby preventing water evaporating and bugs getting in, The Daily Telegraph reported. In fact, the discovery into how trees take on their winter aspect follows a study explaining the bright colours of autumn foliage. And, in their new study, the researchers at Missouri University has revealed that the genetic path
