HE Zi-Can, ZHONG Yang, LIU Hong-Tao, TANG Xian-Hua, YE Li, HUANG De-Shi
J Syst Evol. 2000, 38(2): 121-136.
There are various arguments on classification of the genus Actinidia Lindl., a genus with
approximately 63 species, 59 of which have been found in China. The paper investigated the characteristics of foliar trichomes of 35 taxa from China under optical microscope, including size, celluar
structure, distribution and density. According to their micromorphological characteristics, foliar
trichomes can be classified into the following six categories: 1) single-cell hairs; 2) uniseriate
hairs, including linear, bulbous, twisted, straight-walled, and bent-walled hairs; 3) multiseriate
hairs, including twisted, straight-walled and gradually sharpening, straight-walled and suddenly
sharpening, bent-walled and gradually sharpening, and suddenly sharpening hairs; 4) multiseriate
thick hairs, including pillar hairs, gradually sharpening thick hairs, and suddenly sharpening thick
hairs; 5) stellate hairs, including parenchyma-stellate and sclerenchyma-stellate (normal state and
special states such as rosulate, peltate-stellate, and overlopping-stellate) hairs; and 6) dichotomous hairs. On the basis of the micromorphological characteristics of foliar trichomes in Actinidia,
with Clematoclethra lasioclada as an outgroup, both the quantitative cladistic analysis and phenetic
analysis were performed using Wagner method and UPGMA clustering method respectively to reconstruct the phylogeny of Actinidia in China. The phylogenetic tree generated by cladistic analysis suggests that the sect. Leiocarpae be a monophyletic group, but other three sections, i.e., sect. Maculatae, sect. Strigosae and sect. Stellatae, be non-monophyletic groups. The results obtained from
the phenetic analysis reflect relationships among the taxa of Actinidia in China, especially a close
relationship between A. chinensis and A. deliciosa, and a relatively remote relationship between
A. callosa var. henryi and A. callosa var. discolor. In conclusion, the micromorphological characters of foliar trichomes and the methods of quantitative taxonomic analysis are of key importance tostudies on phylogenetic and phenetic relationships of Actinidia.