Paternity analysis-based inference of pollen dispersal patterns, male fecundity variation, and influence of flowering tree density and general flowering magnitude in two dipterocarp species.
OBJECTIVE
Knowledge of pollen dispersal patterns and variation of fecundity is essential to understanding plant evolutionary processes and to formulating strategies to conserve forest genetic resources. Nevertheless, the pollen dispersal pattern of dipterocarp, main canopy tree species in palaeo-tropical forest remains unclear, and flowering intensity variation in the field suggests heterogeneity of fecundity.


METHODS
Pollen dispersal patterns and male fecundity variation of Shorea leprosula and Shorea parvifolia ssp. parvifolia on Peninsular Malaysian were investigated during two general flowering seasons (2001 and 2002), using a neighbourhood model modified by including terms accounting for variation in male fecundity among individual trees to express heterogeneity in flowering.


RESULTS
The pollen dispersal patterns of the two dipterocarp species were affected by differences in conspecific tree flowering density, and reductions in conspecific tree flowering density led to an increased selfing rate. Active pollen dispersal and a larger number of effective paternal parents were observed for both species in the season of greater magnitude of general flowering (2002).


CONCLUSIONS
The magnitude of general flowering, male fecundity variation, and distance between pollen donors and mother trees should be taken into account when attempting to predict the effects of management practices on the self-fertilization and genetic structure of key tree species in tropical forest, and also the sustainability of possible management strategies, especially selective logging regimes.
Tani
Naoki
N
Forestry Division, Japan International Research Centre for Agricultural Sciences, Ohwashi, Tsukuba, Ibaraki 305-8686, Japan. ntani@affrc.go.jp
Tsumura
Yoshihiko
Y
Kado
Tomoyuki
T
Taguchi
Yuriko
Y
Lee
Soon Leong
SL
Muhammad
Norwati
N
Ng
Kevin Kit Siong
KK
Numata
Shinya
S
Nishimura
Sen
S
Konuma
Akihiro
A
Okuda
Toshinori
T
D053958:Dipterocarpaceae / Q000502:physiology*; D017753:Ecosystem; D005298:Fertility; D035264:Flowers / Q000502:physiology*; D007178:Inbreeding; D008296:Malaysia; D008954:Models, Biological; D054817:Pollination; D011156:Population Density; D014329:Tropical Climate