Saturday, August 6, 2016

Dancing Young Sunflowers

Sun Worship: Those beautiful young yellow plants, sunflowers (Helianthus annuus), act in accordance with their internal clock to face the sun as much as possible, which helps them grow bigger. (Such is the case with immature sunflowers; mature sunflowers tend to always face east.) The next step in the study is to determine which genes regulate the plant's movements. Sarah Crespi writes for Science magazine: “Every day, young sunflowers follow the sun like spectators at an incredibly slow tennis match. But scientists have never known why, or why the tracking stops when they become adults. Now, a new study suggests that this daily sun worship is guided by circadian rhythms during development. In a series of experiments, scientists tied down young plants to prevent them from moving or rotated them so they were facing the wrong way when the sun rose. When the plants’ normal movements were thwarted, they grew far more slowly than regular sunflowers, with about a 10% decrease in both biomass and leaf area. Researchers say the rhythmic tracking helps the plants grow bigger, allowing them to add cells on whichever side is doing the ‘stretching’: the east side during the day and the west side at night.” 
Video Credit & Source: Science