Acacia mangium. Studies on the Genetic Variation in Ecological and Physiological Characteristics of a Fast-Growing Plantaton Tree Species

Helsinki

1989

92 S.

34 Abb., 37 Tab., zahlr. Lit. Ang.

Bandaufführung

2623

36943

Genetic variation in the physiological characteristics and biomass accumulation was studied in both field and laboratory conditions. Variation in the growth characteristics, foliar nutrient concentration, phyllode anatomy and stomatal frequency was analyzed in 16 different origins under field conditions in Central Thailand. Family variation and heritability of growth and flowering frequency were calculated using 20 open-pollinated families at the age of 28 months. The effect of environmental factors on diameter growth in different provenances is also discussed. Under laboratory conditions, such physiological characteristics as transpiration rate, leaf conductance and leaf water potential were measured at varying soil moisture conditions. The responses of photosynthesis, photorespiration and dark respiration as well as the CO2 compensation point to temperature and irradiance were also investigated. All physiological characteristics indicated differences among provenances. An attempt was made to relate the results obtained in the laboratory to the growth performance in the field. Recommendations on provenace selection for the planting of A. mangium in Thailand are also given.