Abstract: Acorns, nuts/seeds of Quercus plants, are commonly infested by insect larvae under natural condition, and consequently, seed quality, germination and seedling recruitment are impacted by infestation. From 2007 to 2008, insect infestation of nuts of Chinese cork oak, Quercus variabilis, was investigated in Jiyuan of Mt. Taihangshan area, and infested and perfect nuts were selected and planted in soil of 4 cm depths in Sep., 2007. We aimed to understand the effects of infestation on acorn quality, germination, seedling growth, and to clarify the interaction between infestation and above-mentioned procedure within plant recruitment. The results showed that: 1) infested rates of nuts were 30.04% and 47.68% in 2007 and 2008, respectively; 2) tannic acid (TA) content in infested nuts (11.54%±1.36%) was significantly larger than that in perfect ones (7.36%±1.31%) (P=0.004); 3) the fresh-weight, diameter, and length of infested acorns were less than those in perfect nuts; 4) the rates of rotten nuts (28%) and partially germinated nuts (28%) in infested nuts were larger than those in perfect nuts (0% rotten and 2% partially germinated), while seedling establishment rate in infested nuts (56%) was less than that in perfect nuts (92%); germination duration of infested nuts (35 weeks after burial) was shorter than that of perfect nuts (37 weeks after burial); 5) at the time of early winter of experimental year, there were insignificant differences in height and leaf number of seedlings between infested and perfect nuts; and 6) at the end of experiment, June, 2008, there were no significant differences in leaf number, stem length, leaf weight and stem weight, except for root length, root weight and biomass, between seedlings derived from infested and perfect nuts. The results suggest that infestation would exert negative impact on seed quality and germination behavior; nonetheless, infestation is presumably reasonable for Quercus plant regeneration owning to decreased predation on infested acorns by other seed eaters.

Key words: Insect infestation, Quercus variabilis, nut, seed quality, germination, plant-animal interaction