Posted: October 28, 2009

Carbon nanotubes fast forward seed germination

(Nanowerk News) A collaborative team of biologists and nanotechnologists from UALR – the University of Arkansas at Little Rock – have demonstrated how seeds exposed to carbon nanotubes in the agar medium sprouted up to two times faster than control seed, a growth enhancement that has enormous potential on agriculture as well as plant-based biofuel production.
Drs. Mariya V. Khodakovskaya, UALR assistant professor of applied science, and Alex Biris, director of the Nanotechnology Center at UALR, published the results of their findings in this month’s issue of ACS Nano.
The results of the UALR experiments demonstrated, apparently for the first time, that carbon nanotubes can penetrate thick seed coat and quicker water uptake inside seeds.
“The activated process of water uptake could be responsible for the significantly faster germination rates and higher biomass production for the plants that were exposed to carbon nanotubes,” the scientists said.
To test their theory that synthesized carbon nanotubes could affect germination and development of crop seedlings, the UALR team placed sterile tomato seeds on standard agar medium supplemented with different concentrations of carbon nanotubes. A medium without the tubes was used for controlled experiments.
Tomato seeds placed on medium with various concentrations of carbon nanotubes (CNTs) germinated on the third day, while the tomato seeds placed on regular mediums had not germinated by that time. The germination percentage rates during the next days were dramatically higher for seeds that were treated with nanoparticles.
The germination percentage for seeds that were placed on regular medium averaged 32 percent in 12 days and 71 percent in 20 days, while germination percentage of the seeds placed on medium supplemented with CNTs averaged 74 to 82 percent in 12 days and 90 percent in 20 days.
The scientists report the first evidence that CNTs penetrate the hard outer coating of seeds, and have beneficial effects.
Nanotube-exposed seeds sprouted up to two times faster than control seeds and the seedlings weighed more than twice as much as the untreated plants. Those effects may occur because nanotubes penetrate the seed coat and boost water uptake, the researchers said.
(We have reported in detail about this work in our Nanowerk Spotlight "Nanotechnology dramatically affects plant growth ")
Source: University of Arkansas at Little Rock