In article <19980328.200531.9742.1.Rkurtz1 at juno.com>,
Richard M Kurtz <rkurtz1 at juno.com> wrote:
>>I have a student in my high school biology class who did a project about
>the effect of touching or repeated rubbing of grass. He also exposed the
>plants to wind (fan). He found that plants rubbed or exposed to wind
>grew differently than those that were not exposed to these factors. In
>general, physical stimulation of the grass resulted in slightly stunted
>growth in height and increase in width. Does anyone know of any
>information related to our findings. Is this effect called
>thigmotropism? Can anyone suggest some papers or books related to my
This response is used by bedding plant growers to grow more compact
transplants in greenhouses. Devices are available that slowly draw
a bar across a greenhouse bench to brush the plants. On a smaller
scale, people who grow their own transplants can get better results
by running a hand over the top of the plants once or twice a day.
Dr. Thomas Bjorkman at Cornell has done some work on this application.
You can get some references from his web page. Your student may also
want to contact greenhouse equipment suppliers to learn about commercial
applications of this effect.