IAWA Bulletin n.s., Vol. 13 (3),1992: 307-349 WOOD STRUCTURE OF THE ROSACEAE IN RELATION TO ECOLOGY, HABIT AND PHENOLOGY by Shu-Yin Zhang!, Pieter Baas! and Marinus Zandee2 Summary Twelve wood anatornical characters, to­ deae and Spiraeoideae are mainly shrubby; gether with broad parameters from ecology, the Maloideae and Prunoideae mainly arbores­ habit and phenology were subjected to simple cent. Phenology mainly influences ray size correlation analysis, path analysis and prin­ and composition and vessel diameter, but cipal component analysis, in a total sampie of does, in our sampIe, not influence ring-por­ over 470 specimens belonging to 271 species osity. of the Rosaceae from the entire distribution Most of the above trends are in accordance area of the farnily. The functional, develop­ with reports on other families or regional mental and systematic implications of the re­ floras. Part of the variation in vessel charac­ sulting relations are discussed. Based on the ters is interpreted as the result of functional present analysis of ecological trends and pre­ adaptation for efficient or safe hydraulic ar­ vious phylogenetic analysis, a tentative sce­ chitecture. nario for the evolution of the Rosaceae is A principal component analysis (PCA) offered. produces three more or less recognisable The four non-anatornical variables (viz. groups: the Maloideae, the Spiraeoideae p.p., macroclimate, moisture availability, habit, and together with the Rosoideae, and the Prunoi­ phenology) show dose mutual correlations. deae. The representatives of the QuiIIajeae Therefore, simple correlation analysis cannot (usually placed in the Spiraeoideae) are dis­ properly reflect intrinsic relations between tributed near the centre of the scatter plot in wood anatornical characters and ecological the Maloideae and Prunoideae. Ray features factors, habit and phenology, and sometimes and vessel element length appear to be the even is misleading. After standardising all most important characters giving rise to this data for the mutual correlations of the ecologi­ result. cal parameters, and habit and phenology, and Key words: Ecological, functional, develop­ the mutual dependencies of most wood ana­ mental wood anatomy, systematics, evo­ tornical characters, only a lirnited number of lution, Rosaceae, habit, phenology, ves­ significant correlations between the non-ana­ sels, rays, ring-porosity, crystals. tomical and wood anatornical parameters remain (Table 15). These correlations only Introduction explain a low proportion of the total variation The Rosaceae constitute a chiefly woody recorded (usually 3-10% for single ecological family with a wide ecological range (from factors). Macroclirnate affects vessel diameter mesic to dry habitats; from cold temperate to and the incidence of crystals. Moisture avail­ hot tropical regions), different kinds of habit ability influences vessel element length. Habit (from tall trees to shrubs, subshrubs, dim­ is mainly related to ring-porosity, vessel fre­ bers or herbs) and phenology (from decidu­ quency, vessel element length, vessel diam­ ous to evergreen), and a large wood anatorni­ eter, ray height and ray composition. It is cal diversity (Zhang & Baas 1992; Zhang also related to systematic position: the Rosoi- 1992). It is thus feasible to study wood struc- 1) Rijksherbarium/Hortus Botanicus, P.O. Box 9514, 2300 RA Leiden, The Netherlands. 2) Institute of Theoretical Biology, Kaiserstraat 63, 2311 GP Leiden, The Netherlands. Downloaded from Brill.com10/07/2021 07:51:36AM via free access 308 IAWA Bulletin n.s., Vol. 13 (3),1992 ture in relation to different abiotic and biotic wood anatomical characters by assessing their factors (viz. ecology, habit, and phenology) dependence on ecological factors. in this family. As explained in the materials and methods A number of studies on the relations of seetion, the quality and degree of detail of the wood structure to ecology were reported with­ ecological information leaves much to be de­ in species (Van Buijtenen 1958; Denne 1971, sired for most species studied. An attempt to 1974,1976; Jenkins 1975; Nicholls & Wright answer the above questions can therefore be 1976; Zhang et al. 1988), in genera (Baas preliminary at best as far as the analysis of 1973; Car1quist 1982a; Dickison et al. 1978; ecological trends is concemed. Van der Graaff & Baas 1974; Van den Oever et al. 1981), in families (Baas & Zweypfen­ Materials and Methods ning 1979; Baas et al. 1988; Car1quist 1966, 1977b, 1978, 1982b, 1984b; Dickison & Materials Phend 1985; Rury 1985; Rury & Dickison Over 470 samples bel on ging to 271 spe­ 1984), and in regional floras (Baas & Carl­ eies of Rosaceae were quantified wood ana­ quist 1985; Baas & Schweingruber 1987; tomically. Over half of the samples were col­ Baas et al. 1983; Carlquist 1977a; Carlquist lected from China (see Zhang & Baas 1992), & Hoekman 1985), and some general eco­ the remaining samples were from different logical trends were established (for reviews parts around the world (see Zhang 1992). Of see Baas 1976, 1982, 1986; Carlquist 1975, the specimens studied, most are from sub­ 1980, 1988). Less attention, however, has tropieal and temperate regrons, while a limit­ been paid to habit in relation to wood struc­ ed number of specimens are from tropical ture (e.g., Baas & Zweypfenning 1979: Baas regions. & Schweingruber; Baas et al. 1983: Baas et al. 1984; Carlquist 1966, 1984b; Rury & Parameters analysed Dickison 1984). So far there are relatively few The present study, like many earlier stud­ reports on the correlations of phenology with ies of ecological wood anatomy, suffers from wood structure (e.g. Baas & Zhang 1986; insufficient ecological data. No ecologieal in­ Car1quist 1988; Chowdhury 1964). formation is available on the sampies from In the present study the diversity in vari­ the FHOw eollection. For the sampies from ous wood anatomie al characters in relation to China, the locality is usually known, but fur­ ecological factors (e.g. macroclimate and ther information (e.g., altitude, plant size, moisture availability), habit, and phenology water availability) is limited to certain sam­ will be analysed in order to answer the fol­ pIes (viz., the sampies from Zhongtiao and lowing questions: 1) How and to what extent Yunnan). Ecological information for the Chi­ is wood structure related to the rough ecolog­ nese samples was therefore based mainly on ical parameters analysed? 2) How and to what floristic literature (Wu 1980; Yu 1974, 1985, extent are various wood anatomical charac­ 1986). For the samples from Schweingruber, ters related to habit and phenology on the one Carlquist, and those from Israel, the relevant hand, and among themselves on the other? publieations (Baas & Schweingruber 1987: 3) How and to what extent are the effects of Carlquist & Hoekman 1985; Baas et al. 1983; macroclimate, moisture availability, habit and Fahn et al. 1986) have offered the necessary phenology on wood structure interrelated? ecological data. The eeological information 4) How and to what extent do the mutual de­ for the sampies from Dechamps was based pendencies of wood anatomical features af­ on the field data attached with the sampIes. feet the ecological trends? Wormation on phenology and habit was main­ Earlier studies on the wood anatomie al di­ Iy based on Mabberley (1987), Hutehinson versity of the Rosaceae (Zhang & Baas 1992; (1964) and Yu (1974,1985,1986). In addi­ Zhang 1992) serve as a basis of our present tion to the limited and rough data mentioned study. In return, this study is also aimed at above, non-standard sampling may also have increasing our understanding of the system­ influeneed the quantitative data. However. it is arie and biologie al significance of various believed that these random sources of varia- Downloaded from Brill.com10/07/2021 07:51:36AM via free access Zhang, Baas & Zandee - Wood structure of the Rosaceae 309 tion cannot have influenced the general re­ categories, however, were recognised in this sults appreciably. study. 1) Shrubs: here including shrubs, sub­ For the purpose of statistical quantifica­ shrubs, and perennial herbs; 2) Trees: woody tion, the following broad ecological and habit plants that attain a height of at least 7 m at categories were recognised: maturlty; 3) Intermediate-sized plants: large Macroclimatic zones - 1) Temperate spe­ shrubs to small trees. eies (occurrlng above 32° N or S latitude); 2) Subtropical species (occurring between In total, 12 wood anatomical characters 23° 30' and 32° N or S); 3) Tropical species were analysed. These characters include not (occurrlng between 23° 30' N or S; for the only qualitative but also quantitative ones: Chinese species, those occurrlng in Taiwan, ring-porosity, vessel frequency, percentage Hainan, southern Guangdong and southern of solitary vessels, (tangential) vessel diam­ Yunnan were treated as tropical elements). eter, vessel element length, length/diameter This classification ignores vast altitudinal (LID) ratio of vessel elements, multiple per­ variation within each region. forations, helical vessel wall thickenings, ray width, multiseriate ray height, ray composition Moisture availability - The same very and crystals. For definition and measurement rough and arbitrary categories as recognised of these features, see Zhang & Baas (1992). by Baas and Schweingruber (1987) for the All data analysed are given in Table 1. For European flora were adopted. 1) Dry: species statistical analysis, the qualitative parameters from physically