Carry-over effects of ozone and water stress on leaf phenological characteristics and bud frost hardiness of Fagus crenata seedlings

Abstract

We examined the carry-over effects of ozone (O 3 ) and/or water stress on leaf phenological characteristics and bud frost hardiness of Fagus crenata seedlings.Three-year-old seedlings were exposed to charcoal-filtered air or 60 nl l −1 O 3 , 7 h a day, from May to October 1999 in naturally-lit growth chambers. Half of the seedlings in each gas treatment received 250 ml of water at 3-day intervals (well-watered treatment), while the rest received 175 ml of water at the same intervals (water-stressed treatment). All the seedlings were moved from the growth chambers to an experimental field on October 1999, and grown until April 2000 under field conditions. The exposure to O 3 during the growing season induced early leaf fall and reduction in leaf non-structural carbohydrates concentrations in the early autumn, as well as resulting in late bud break and reduction in the number of leaves per bud in the following spring. However, O 3 did not affect bud frost hardiness in the following winter. On the contrary, water stress did not affect leaf phenological characteristics, leaf and bud non-structural carbohydrates concentrations and bud frost hardiness. There were no significant synergistic or antagonistic effects of O 3 and water stress on leaf phenological characteristics, concentrations of leaf and bud non-structural carbohydrates and bud frost hardiness of the seedlings. These results show that the carry-over effects of O 3 can be found on the phenological characteristics and leaf non-structural carbohydrates concentrations, although there are almost no carry-over effects of water stress on phenological characteristics and winter hardiness of the seedlings.

Growth and physiological responses to ozone and mild drought stress of tree species with different ecological requirements

“…A small number of papers, however, have reported that a transitory increase in growth can be observed during the first treatment period (Rebbeck and Scherzer 2002), or as a consequence of exposure to moderate ozone concentrations . A combination of ozone and drought can exacerbate the overall effect (Alonso et al 2001;Yonekura et al 2001Yonekura et al , 2004Grulke et al 2004;Ribas et al 2005;Tausz et al 2007). Several explanations have been suggested for this behaviour, including an excessive production of reactive oxygen species (ROS) due to the concomitant action of the two stressors (Tausz et al 2007) and altered stomatal function due to ozone (stomata remain open or their closure is slowed in drought stress conditions, see Maier-Maercker 1989;McLaughlin and Downing 2002;Grulke et al 2002).…”

Growth and photosynthetic responses of Fagus crenata seedlings to O3 under different nitrogen loads

“…In Japan, relatively high concentrations of O 3 above 100 nl l -1 (ppb) have been frequently observed from spring to autumn in several mountainous areas (Maruta et al 1999;Aihara et al 2004;Takeda and Aihara 2007). Although limited information on the effects of O 3 on Asian forest tree species is available, several Japanese researchers have suggested that ambient levels of O 3 reduce growth and net photosynthesis of Japanese forest tree species (Izuta et al 1996;Matsumura 2001;Yonekura et al 2001aYonekura et al , 2001bYonekura et al , 2004Matsumura et al 2005). In the near future, furthermore, concentration of ground-level O 3 is expected to increase in many parts of the world, especially in Asian countries (Emberson et al 2001;Derwent et al 2002).…”

Effects of acidic fog and ozone on the growth and physiological functions of Fagus crenata saplings

“…The O 3 concentrations were determined based on data for atmospheric O 3 obtained in the Tanzawa Mountains, where high concentrations of O 3 are detected with a mean O 3 concentration of approximately 60 ppb (Yonekura et al 2004). The chamber was 1.2 9 1.2 9 1.2 m high, with a volume of 1.73 m 3 , and was made of an aluminum framework with polyvinyl chloride sheeting on all sides except for the floor.…”

“…Recently, Takeda and Aihara (2007) examined beech saplings exposed to unfiltered air or charcoal-filtered air in an open-top chamber on the Tanzawa Mountains and reported that their total biomass was reduced considerably in the unfiltered air. As described, air pollutants such as acid fog and O 3 are common environmental stresses for beech seedlings (Shigihara et al 2008a;Yonekura et al 2004), but the effects of acid fog and O 3 have been considered separately thus far. Although few studies to date have examined the interactive effects of acid fog and O 3 on vegetation, such studies must produce more accurate predictions of future ecosystem responses to the changing environment.…”