Frost resistance of reproductive tissues during various stages of development in high mountain plants
Version of Record online: 16 APR 2012
Copyright © Physiologia Plantarum 2012
Special Issue: Abiotic Stress
Volume 147, Issue 1, pages 88–100, January 2013
How to Cite
Neuner, G., Erler, A., Ladinig, U., Hacker, J. and Wagner, J. (2013), Frost resistance of reproductive tissues during various stages of development in high mountain plants. Physiologia Plantarum, 147: 88–100. doi: 10.1111/j.1399-3054.2012.01616.x
- Issue online: 17 DEC 2012
- Version of Record online: 16 APR 2012
- Accepted manuscript online: 15 MAR 2012 10:35AM EST
- Received 14 November 2011; revised 26 January 2012
Frost resistance of reproductive vs aboveground vegetative structures was determined for six common European high alpine plant species that can be exposed to frosts throughout their whole reproductive cycle. Freezing tests were carried out in the bud, anthesis and fruit stage. Stigma and style, ovary, placenta, ovule, flower stalk/peduncle and, in Ranunculus glacialis, the receptacle were separately investigated. In all species, the vegetative organs tolerated on an average 2–5 K lower freezing temperatures than the most frost-susceptible reproductive structures that differed in their frost resistance. In almost all species, stigma, style and the flower stalk/peduncle were the most frost-susceptible reproductive structures. Initial frost damage (LT10) to the most susceptible reproductive structure usually occurred between −2 and −4°C independent of the reproductive stage. The median LT50 across species for stigma and style ranged between −3.4 and −3.7°C and matched the mean ice nucleation temperature (−3.7 ± 1.4°C). In R. glacialis, the flower stalk was the most frost-susceptible structure (−5.4°C), and was in contrast to the other species ice-tolerant. The ovule and the placenta were usually the most frost-resistant structures. During reproductive development, frost resistance (LT50) of single reproductive structures mostly showed no significant change. However, significant increases or decreases were also observed (2.1 ± 1.2 K).
Reproductive tissues of nival species generally tolerated lower temperatures than species occurring in the alpine zone. The low frost resistance of reproductive structures before, during and shortly after anthesis increases the probability of frost damage and thus, may restrict successful sexual plant reproduction with increasing altitude.