Abstract
Keteleeria davidiana var. formosana is an indigenous tree native only to the northern Pinglin and southern Dawu areas of Taiwan. It is listed as a protected species by the Taiwanese government due to the scarcity of its populations and low seed production. Cones of 10 naturally pollinated Keteleeria mother trees were collected from the Taipei Botanical Garden, Taipei’s Lishui Street, Yangmingshan, Chushui River nursery, Fushan Botanical Garden, Pinglin’s Jingualiao River, and Pinglin’s Shicao in 2002~2010. The number of filled seeds to total number (filled+empty) of seeds per cone was consistently < 1% in the Taipei Botanical Garden. Single mother trees at Lishui Street and Yangmingshan were naturally self-pollinated, and seed efficiency per cone ranged 0.03~3.4% during the study period, except for cones collected in 2004 for which seed efficiencies per cone were 10.1 and 7.1%, respectively. The mother trees at Pinglin’s Jingualiao River and Pinglin’s Shicao were located in natural populations, and seed efficiencies per cone, which were determined only in 2009, were 2.8 and 19.1%, respectively. Cone production was irregular, with good masting every 3~5 yr. Cone production varied from 1 population to another during a good masting year, and it also differed within a population, i.e., some mother trees produced abundant cones but others did not. For controlled pollination, pollen of 1 genotype from Yangmingshan and 1 from southern Daren were used. Seed efficiencies per cone for both areas were 14.7~37.9% in controlled pollination compared to 0.08% for self-pollination. For supplemental mass pollination, dried pollen with 53~96% germination stored at -20℃ for 5 yr was used. Seed efficiencies per cone ranged 5.0~48.2%, which were greater than that of natural pollination. trnD-trnY and trnV intron intergenic spacer analyses showed that chloroplast DNA is paternally inherited.