Plant Cognition: Ability to Perceive ‘Touch’ and ‘Sound’
Plants’ sessile life-style has enabled them to develop enormous sensitivity towards their dynamic, tactile and clamorous surroundings. Consequently, besides a range of different stimuli, plants can even perceive subtle stimuli, like ‘touch’ and unanticipatedly ‘sound’. Importantly, touch sensitivity in plants is not just limited to sensitive plant and carnivorous species, which respond through eye-catchy movements; instead every plant and living plant cell senses and responds to mechanostimulation, whether intrinsic or extrinsic in nature. For instance, plant roots are extremely touch-sensitive, and upon encountering a barrier in soil, they are able to effectively redirect their growth to transcend it. Similarly, tendrils in climbing plants exhibit extreme sensitivity towards touch, which enable them to sense and grab a support in close vicinity. Unlike touch sensitivity, which was recognized long ago by Robert Hooke and Darwin, plants’ sensitivity towards sound has started gaining attention only recently. The past decade has seen major advances in this area of plant biology; many breakthrough discoveries were made that revealed the, otherwise debatable, ecological significance of sound perception in plants’ life. It has come to light that plants not just sense but also distinguish relevant sound among a mixture of irrelevant sound frequencies; plants distinguish buzz produced by a true pollinator among pollen thieves in the sophisticated process of buzz pollination. Similarly, plants distinguish sound typical of a herbivore for elicitation of defence response. Interestingly, plant roots can sense sound of flowing water in order to direct their growth towards the water source. Given the similarity in the physical properties of touch and sound stimuli, many recently discovered signaling events and molecular players in touch and sound perception are noted to be common. However, in view of the contrasting responses tailored according to the stimuli, plants appear to distinguish well among the two in an ecologically meaningful manner.
KeywordsCognition Development Growth Mechanoperception Plant acoustics Sound Thigmonasty Thigmotropism Touch Volatile organic compounds
This work was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (NRF-2017R1D1A1B03030357).
- Jeong MJ, Cho JI, Park SH, Kim KH, Lee SK, Kwon TR, Park SC, Siddiqui ZS (2014) Sound frequencies induce drought tolerance in rice plant. Pak J Bot 46:2015–2020Google Scholar
- Retallack DL (1973) The sound of music and plants. DeVorss, Santa MonicaGoogle Scholar
- Tompkins P, Birds C (1973) The secret life of plants. Harper & Row, New YorkGoogle Scholar
- Wang K, Yang Z, Qing D, Ren F, Liu S, Zheng Q, Liu J, Zhang W, Dai C, Wu M, Chehab EW, Braam J, Li N (2018) Quantitative and functional posttranslational modification proteomics reveals that TREPH1 plays a role in plant touch-delayed bolting. Proc Natl Acad Sci U S A 115:E10265–E10274CrossRefGoogle Scholar