摘要
Aims Genetic variation in plant traits represents the raw material for future adaptive evolution.Its extent can be estimated as heritability based on the performance of experimental plants of known relatedness,such as maternal half-sib seed families.While there is considerable heritability information for herbaceous plants and commercially important trees,little is known for woody species of natural subtropical forest.Moreover,it is open whether heritability is higher for species with r-or K-strategies,for more common species with larger distribution ranges than for rarer ones,or for populations closer to the centres of distributional ranges.Methods For 14 woody species in Chinese subtropical forest,we collected 13-38 maternal seed families,assessed seed size,grew replicates of each seed family in one more and one less benign nursery environment and measured stem diameter and plant height after 7 months.Important findings For the different species,plants grew 1.8-8.1 times taller in the more benign environment.For all 14 species,variation between seed families(and thus heritability)was significant(with very few exceptions at the P<0.001 level)for seed size and for stem diameter and plant height in both nurseries.Moreover,significant seed family by nursery interactions for stem diameter and plant height for all species(P<0.001)indicated significant heritability for plasticity in these traits.Multiple regression analysis suggests that heritabilities were higher for species with higher age at reproduction and higher wood density(traits indicating a K strategy)but also for species with higher specific leaf area(a trait rather indicating an r strategy).Furthermore,heritabilities were higher for species with larger range sizes,while there was no significant relationship between heritabilities and the distance of the study area to the range margins of our study species.In conclusion,the detected large heritability estimates suggest considerable potential for the evolution of plant performance and its plasticity for tree
基金
the consortium of BEF-China(www.bef-china.de)for the excellent intercultural and scientific team spirit
the German Science Foundation DFG for funding.
