Scientists have discovered how plants manage to live alongside each other in places that are dark and shady. Plants in the deep darkness of a thick forest, where natural supplies are not very great in amount, won't attempt to top their neighbors in growth as those in moderate (中度的) shade do. In deep shade conditions, it would be a waste of energy and harmful to survival because green shoots would never be able to top their larger neighbors in growth.
So how do plants prevent such growth in deep shade conditions? The secret lies in the clocks inside them, say scientists from the John Innes Centre and the University of Bristol.
They have discovered that when plants notice deep shade, this changes the expression of genes in certain parts of the circadian clock (昼夜节律时钟) — the internal daily timer found in plants and other living things. These clock components perform an additional role in preventing plants from lengthening and overtopping neighbors.
The work identifies a previously unknown role of the circadian clock in controlling plant development, and the findings may have possible effects on both natural plant populations and crops. Professor Antony Dodd of the John Innes Centre said, "The biological clock of plants plays a big part in their development and fitness. This work casts new light on a new role of the circadian clock in adapting plants to competition with other plants in their environments." "It also gives us new insights into how plants adapt to very deep shade, where resources are very limited," said Professor Kerry Franklin at the University of Bristol.
This work provides evidence for the stability of the circadian clock in stressful environments, and information that may be useful in developing new generations of crops in a challenging climate.
