Selection for biomass production based on respiration parameters in eucalypts: effects of origin and growth climates on growth rates

Abstract

Seventeen Eucalyptus species and 30 rapid-growing Eucalyptuscamaldulensis trees (referred to as plus trees), growing in a plantation were studied to examine relationships among measured plant growth and respiratory parameters, geographical origins, and growth climate. The respiratory parameters measured at two different temperatures by isothermal calorimetry were metabolic heat rate, rate of CO2 production, and the ratio of heat rate to CO2 rate. Metabolic heat rate was also measured as a continuous function of temperature by differential scanning calorimetry in the range of 10 to 40 °C. Tree growth was measured as rates of height and stem volume growth. The values of respiratory and growth variables of Eucalyptus species are significantly correlated with latitude and altitude of origin of their seed sources. The maximum metabolic heat rate, the temperature of the maximum heat rate, the temperature coefficients of metabolic rate, and the temperatures at which the slopes of Arrhenius plots change are all genetically determined parameters that vary both within and among species. Measurement of growth rate–respiration rate–temperature relationships guide understanding of why relative growth rates of Eucalyptus species and individual genotypes differ with climate, making it possible to identify genotypes best suited for rapid growth in different climates. The temperature dependence of respiration rates is an important factor determining relative growth rates of eucalypts in different climates. To achieve optimum biomass production the temperature dependence of individual plants must be matched to growth climate.

Contrasting adaptation of twoEucalyptussubgenera is related to differences in respiratory metabolism

“…Figure 3 establishes that a unique combination of respiratory parameters exists for each of the Eucalyptus species and that the combinations of respiratory patterns characteristic of Symphyomyrtus differ from those of Monocalyptus . Because respiratory properties are major determinants of plant growth rates and responses to environment, a tight link exists between respiration properties and adaptation to a given environment (Anekonda, Criddle & Libby 1994; Anekonda, Criddle, Libby, Breidenbach & Hansen 1994, Criddle et al 1994, 1995; Anekonda et al 1996; Criddle, Anekonda et al 1996; Criddle, Smith & Hansen 1997).…”

“…The most likely selective environmental force causing respiratory metabolic adaptation is climate and the most likely climatic factor is temperature (Levitt 1980; Berry & Raison 1981; Davidson & Reid 1985; Sakai & Larcher 1987; Booth & Pryor 1991; Criddle et al 1994, 1995; Jeffree & Jeffree 1994, 1996; Criddle, Anekonda et al 1996). Plant distributions are closely linked to seasonal temperature, and metabolic responses are closely linked to diurnal and seasonal temperature changes (Criddle et al 1994; Anekonda et al 1996). Respiration parameters measured over a range of temperatures successfully predict the growth temperature ranges of plants as diverse as tomato and cabbage (Criddle, Smith & Hansen 1997).…”

“…The trees were all well watered and fertilized so that the major uncontrolled variable affecting growth was temperature. Diurnal temperature variation at Corning is generally greater than at the growth sites of the test species in Australia (Anekonda et al 1996). The trees therefore experience temperatures outside their normal range for much of the growth season at Corning.…”

“…Plant material used in this study consisted of seed sources of nine Symphyomyrtus and six Monocalyptus species grown from individual seed collections obtained by the Simpson Tehama Fiber Farm, primarily from CSIRO Division of Forestry, Australian Tree Seed Center. Some additional collections were from other seed collectors in Australia and from the USDA Eucalyptus programme in Florida (Anekonda et al 1996). These 15 species were planted in May 1992 at Corning, CA.…”

Response to M. Adams

“…Despite our using seed from a variety of sources where rapid growth in the local climate was the major objective, all seed came from wild seed collection, and we have excellent records on origin (latitude, longitude, elevation, and provenance location in Australia) of all the seed sources used in this study. This information was published in another article (Anekonda et al . 1996).…”