The dynamics of leaf extension in plants with diverse altitudinal ranges

Abstract

Rates of leaf extension have been studied with electronic auxanometers at mid-altitude in the Austrian Alps, where both low and high altitude species co-occur. The results demonstrate a clear differentiation in the temperature responses of extension between these two groups of species. For the low or mid-altitude species of Achillea millefolium, Agrostis stolonifera, Poa alpina and Rumex arifolius, the average rate of leaf extension increases from 0.1 to 0.4 mm h between 10 and 20° C. For the high-alpine species of Achillea erba-rotta ssp moschata, Poa alpina ssp vivipara and Polygonum viviparum the average rate of leaf extension was considerably lower from 0.016 to 0.064 mm h, between 10 and 20° C.Leaf extension in the lowland species was not observed below an average temperature of about 5° C, whilst no limit was observed for the upland species, down to a temperature of about 0° C.In the cases of the dicotyledons that were studied, leaf plus petiole shrinkage was observed to occur, for as much as 2 to 4 h, during periods of high water vapour pressure deficits. This response was not observed for the monocotyledons.The observations of leaf extension show that daily totals of extension in species from high altitudies will be much less sensitive to day, to day variations in local climate than will the species from low altitudes. The lowland species will have higher rates of extension during clear and warm weather conditions but lower rates in cold, cloudy weather.

Elevated CO2, water relations and biophysics of leaf extension in four chalk grassland herbs

“…The apparent leaf 'shrinkage' may represent changes in the direction of leaf expansion owing to periclinal and anticlinal cell divisions of cell growth (Maksymowych, 1973). Woodward, Korner & Crabtree (1986) found similar contractions for A. vulneraria spp. alpestris grown m the field and concluded that this was correlated with a decline in atmospheric humidity and, presumably leaf turgor pressure.…”

Specific leaf area correlates with temperature: new evidence of trait variation at the population, species and community levels

“…As a consequence, declining environmental favourability for plant growth should lead to species turnover caused by excluding maladapted species from the plant communities. One could expect that fast-growing species with high temperature thresholds for cell expansion (high SLA values) would be the first species to show decreased abundances in communities along such gradients, being progressively replaced by cold-adapted, slow-growing species with low temperature thresholds for cell extension (low SLA values; Woodward et al 1986;Körner and Woodward 1987a, b). Good examples of this phenomenon in our dataset include the fast-growing species Arrhenatherum elatius (SLA = 29.4 mm 2 mg -1 ) and Leontodon hispidus (SLA = 30.2 mm 2 mg -1 ), which occur in the lowland site conditions and are absent under high-elevation conditions.…”

“…Reduced ambient temperatures and increased temperature stress along elevational or latitudinal gradients lead to species turnover in plant communities, from fastgrowing species with high temperature thresholds for cell expansion to slow-growing species that exhibit cell expansion at lower temperature thresholds (Woodward et al 1986;Körner and Woodward 1987a, b). Low rates of cell expansion relative to the rates of cell wall and protein synthesis in elongating cells as a consequence of slow growth rates (Atkin et al 1996;Körner 1999) lead to a large number of small cells per unit area, and accordingly, smaller and denser leaves on plants in cold habitats (Atkin et al 1996;Poorter et al 2009).…”

Growth response of Mountain birch to air and soil temperature: is increasing leaf‐nitrogen content an acclimation to lower air temperature?

“…Many effects of temperature on plants might act in a complex manner. Major effects of raised air temperature are enhanced leaf expansion rate (Ong & Baker, 1985; Woodward et al. , 1986) and shoot growth rate (Larigauderie et al.…”

“…Many effects of temperature on plants might act in a complex manner. Major effects of raised air temperature are enhanced leaf expansion rate (Ong & Baker, 1985;Woodward et al , 1986) and shoot growth rate (Larigauderie et al , 1991), whereas elevated soil temperature primarily might increase root growth (Tryon & Chapin, 1983;Larigauderie et al , 1991) and nutrient uptake rate (Chapin, 1974;Kummerow & Ellis, 1984;Karlsson & Nordell, 1996). Since plant processes above-and belowground are intimately linked, the ultimate effects of increased temperature on whole-plant growth and single growth parameters often are not obvious.…”