How do I stop growing

Honolulu (dpa) - Anyone who hears the grass growing is usually not taken seriously. However, using a special technique, American scientists have made the growth of corn stalks audible. Corn belongs to the sweet grasses (Poaceae).

Douglas Cook's team from New York University presented its research results at a conference in Honolulu (Hawaii, USA). The findings should help to reduce the losses due to wind breakage in maize cultivation.

So what does it sound like when the grass plant grows corn? Very similar to when a corn stalk breaks, explains Cook, according to a message from the Acoustical Society of America (ASA), which is hosting the conference. "We now believe that plant growth brings about millions of tiny break events, and that those breaks cause the plant to repair the broken regions." By constantly breaking and repairing them, the plant can get bigger and bigger.

Cook suspects that the mechanism may be similar to building muscle in humans. When lifting weights, small mini-cracks would appear. The repair then strengthens the muscle.

According to the Federal Statistical Office, maize was grown on 2.6 million hectares in Germany this year. With an annual harvest of 350 million tons, corn is the most important grain in the United States. However, the yields would be higher if storms did not frequently break the corn stalks there. Scientists have been studying the problem for 100 years, writes the ASA. So far, however, the success has been low.

In their research, Cook and colleagues rely on techniques from the field of mechanical engineering. "A material fracture is like a microscopic earthquake: the sudden release of internal tension sends sound waves that radiate in all directions," explains Cook. The biomechanics used so-called piezoelectric contact microphones to pick up the sounds of the corn. In this way they try to understand what exactly happens when it breaks and when it grows.

The scientists also found that during the rapid growth, the leaves of the plant make a particular contribution to the stability of the stem. Therefore, it could help plant scientists to develop new varieties with harder leaves that are less prone to failure during the growth phase.