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Byline: Kyoko Aoki (1), Takeshi Suzuki (2), Noriaki Murakami (1) Keywords: Chloroplast DNA; Evergreen broad-leaved forest; Intraspecific variation; Lucidophyllous forest; Phylogeography Abstract: For the purpose of phylogeographic study of lucidophyllous (evergreen broad-leaved) forests in Japan, we surveyed intraspecific chloroplast DNA (cpDNA) variation in 41 component species of such forests. Intraspecific cpDNA variations were detected in 14 species. In 15 species and one species group, 16 non-coding cpDNA regions were examined to find intraspecific sequence variation. The extent of variation in these regions was compared. The largest amount of intraspecific variation was detected in the rps16 region. A relatively large amount of intraspecific variation was detected in the petD-rpoA, rpl16, and trnL-F regions. It is suggested that these regions of cpDNA would be useful for detecting intraspecific variation in plant species, and could provide valuable information for various research purposes. Author Affiliation: (1) Department of Botany, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan (2) Division of Biological Resources, Museum of Nature and Human Activities, Sanda, Japan Article History: Received Date: 03/02/2003 Accepted Date: 21/04/2003 Online Date: 19/06/2003

Byline: Yoshio Ino (1), Tomoyuki Maekawa (1), Tomohiro Shibayama (1), Yoshiaki Sakamaki (1) Keywords: Adaptation to heavy snow; Carbohydrate; Evergreen shrub; Matter economy; Respiration; Strategy for wintering Abstract: Plant adaptation to an environment subject to heavy snowfalls was investigated in four species of evergreen shrubs growing in a Fagus crenata forest in an area of Honshu on the Sea of Japan. These shrubs stored carbohydrates in some organs before the snowy season and were covered with snow for 4--5 months. Aucuba japonica var. borealis, Camellia rusticana, and Ilex crenata var. paludosa maintained a reserve of carbohydrates during the snowy season. In Daphniphyllum macropodum var. humile, the reserve of carbohydrates decreased during winter. The respiration rates in the first three species decreased from autumn to winter, whereas the decrease in D. macropodum was slight. It was found that the first three species could use reserve carbohydrates for the growth of new shoots after the thaw, whereas in the last species the growth of new shoots depends on high photosynthetic activity in late spring. Our findings suggest some types of matter economy in evergreen shrubs for wintering in an environment of heavy snow. Author Affiliation: (1) Department of Biology, School of Education, Waseda University, Tokyo 169-8050, Japan Article History: Received Date: 26/09/2002 Accepted Date: 31/03/2003 Online Date: 15/05/2003

Byline: Nozomi Isogai (1), Yasuo Yamamura (1), Shigeru Mariko (2), Takashi Nakano (3) Keywords: Evergreenness; Matter production; Pyrola; Seasonal growth; Subalpine Abstract: The seasonal pattern of growth and matter production of Pyrola incarnata, an evergreen herb on the forest floor in subalpine deciduous forests, was analyzed to understand the ecological significance of evergreenness in a subalpine climate with a short growing season and low temperature. Net production was highest under favorable light conditions in spring after the disappearance of snow cover, and 68% of the annual net production was attained before the canopy tree foliage had fully expanded. Most of the photosynthetic production in this period was carried out with over-wintered leaves. This appears to be an advantage of evergreenness. New leaves and inflorescences had developed in the period. Positive net production was maintained under deteriorating light conditions during summer, when 32% of the annual net production occurred. This production was used mainly for growth of fruits and underground organs. The net production of P. incarnata during summer was much higher than that of a related species that inhabits warm-temperate regions, because of its higher photosynthetic activity rather than its lower respiratory losses. The storage of dry matter in leaves and underground organs was not conspicuous. Unlike the warm-temperate species and another subalpine species that inhabits higher altitudes, P. incarnata is not strongly dependent on its reserve matter for the development of new organs. Author Affiliation: (1) Department of Environmental Sciences, Faculty of Science, Ibaraki University, 2-1-1 Bunkyo, Mito 310-8512, Japan (2) Institute of Biological Sciences, University of Tsukuba, Tsukuba, Japan (3) Yamanashi Institute of Environmental Sciences, Fujiyoshida, Japan Article History: Received Date: 04/03/2002 Accepted Date: 10/02/2003 Online Date: 24/04/2003

Byline: Wu (1), Juei-Er (1), Shong Huang (1), Jenn-Che Wang (1), Wu-Fu Tong (1) Keywords: Keywords: Allozymes, Genetic diversity, Population differentiation, Trochodendron aralioides Abstract: Siebold &amp Zucc., a primitive angiosperm that is insect-pollinated, has wind-dispersed seeds and grows only in eastern Asia. Nineteen populations were analyzed, including 16 from Taiwan, two from the main islands of Japan and one from Iriomote Island in the Ryukyu Islands. Genetic variability (0.133) at the species level was more similar to that of a narrow geographic species than an endemic species. Based on genotype frequencies, mating within populations was non-random (F .sub.I .sub.s=0.065) and there was significant genetic differentiation (F .sub.ST=0.164) among populations. Genetic diversity was largely within, rather than among, populations (H .sub.s=0.132, 85.14%). Bisexual flowers of T. aralioides exhibit synchronized dimorphism. The protogynous and protandrous morphs are self-incompatible, which probably promotes outcrossing and contributes to the high levels of heterozygosity within populations. Using a maximum likelihood tree, populations of T. aralioides were separated into two distinct clusters: Japan and Taiwan/ Iriomote Island. Populations of T. aralioides on Iriomote Island and in northern Taiwan exhibited a high degree of genetic similarity. The isolation-by-distance model does not fit populations in Taiwan, but suitably describes the relationship between populations of T. aralioides in Japan and Taiwan. Author Affiliation: (1) Department of Biology, National Taiwan Normal University, Taipei, 11650 Taiwan, Republic of China, CN Article note: Received 28 April 2000/ Accepted in revised form 13 December 2000

Yucca glauca is a C(sub 3) evergreen rosette species locally common in the C(sub 4)-dominated grasslands of the central Great Plains. Most congeners of Y. glauca are found in deserts, and Y. glauca's morphological similarities to desert species (steeply angled leaves, evergreen habit) may be critical to its success in grasslands. We hypothesized that the evergreen habit of Y. glauca, coupled with its ability to remain physiologically active at cool temperatures, would allow this species to gain a substantial portion of its annual carbon budget when the C(sub 4) grasses are dormant. Leaf-level gas exchange was measured over an 18-mo period at Konza Prairie in northeast Kansas to assess the annual pattern of potential C gain. Two short-term experiments also were conducted in which nighttime temperatures were manipulated to assess the cold tolerance of this species. The annual pattern of C gain in Y. glauca was bimodal, with a spring productive period (maximum monthly photosynthetic rate = 21.1 +/- 1.97 p, (mu)mol*m(super -2)*s(super -1)) in March through June, a period of midseason photosynthetic depression, and a fall productive period in October (15.6 +/- 1.25 (mu)mol*m(super -2)*s(super -1)). The steeply angled leaves resulted in interception of photon flux density at levels above photosynthetic saturation throughout the year. Reduced photosynthetic rates in the summer may have been caused by low soil moisture, but temperature was strongly related (r(super 2) = 0.37) to annual variations in photosynthesis, with nocturnal air temperatures below -5 degrees C in the late fall and early spring, and high air temperatures (> 32 degrees C) in the summer, limiting gas exchange. Overall, 31% of the potential annual carbon gain in Y. glauca occurred outside the 'frost-free' period (April-October) at Konza Prairie and 43% occurred when the dominant C(sub 4) grasses were dormant. Future climates that include warmer minimum temperatures in the spring and fall may enhance the success of Y. glauca relative to the C(sub 4) dominants in these grasslands. Key words: climate change; cold tolerance; evergreen; grasslands; Liliaceae; photosynthesis; tallgrass prairie; water relations; Yucca.

Eastern hemlock (Tsuga canadensis) was a major component of mesic forests in the Upper Great Lakes region, but presently persists in only a few locations. Many of these stands experience poor regeneration due to herbivory by white-tailed deer (Odocoileus virginianus), suggesting that hemlock will become progressively less common in these stands. We tested the hypothesis that balsam fir (Abies balsamea) facilitates establishment of eastern hemlock at 11 sites in northern Wisconsin. Hemlock saplings are three times as dense and twice as tall when growing within patches of balsam fir compared to growing outside such patches. Hemlock saplings growing outside balsam fir patches are also four times as likely to exhibit deer browsing damage as those growing inside. These results suggest that patches of balsam fir create a physical or visual barrier to deer and thus provide a refuge for hemlock saplings from white-tailed deer browsing. Because balsam fir saplings are much more abundant than hemlock in northern Wisconsin forests and establish on a wider range of sites, foresters could use patches of balsam fir to facilitate local hemlock establishment and so promote restoration of this important forest type., INTRODUCTION Eastern hemlock (Tsuga canadensis) is a long-lived, shade-tolerant conifer. In presettlement forests, it was a canopy dominant on mesic sites in the Upper Great Lakes states (Curtis, 1959). It [...]

In gynodioecious species. which contain females and hermaphrodites, the outcrossed seeds of females have been found to outperform the outcrossed seeds of hermaphrodites, in spite of the fact that their seeds are not larger in mass. Females do not make pollen. Hence the nutrients that hermaphrodites allocate to pollen, such as nitrogen, might be allocated to seeds by the females, such that individual seeds from females are better provisioned than those from hermaphrodites. Alternatively, females might make more seeds, rather than better provisioned seeds. We tested the hypothesis that seeds from females would be better provisioned for the gynodioecious species Silene acaulis, by comparing seed mass, embryo/endosperm mass, nitrogen and phosphorus content, and energy content for outcrossed seeds from females and hermaphrodites produced in a natural population. We also measured the proportion of flowers that set fruit in both morphs. Seeds from the two sexual morphs were not found to differ significantly for any of the measures of seed provisioning, with seeds from females containing either nonsignificantly less or equivalent amounts of each of the measures as compared to hermaphrodites. However, females set a significantly higher proportion of their flowers to fruit, as compared to hermaphrodites. These results indicate that females do not provision individual seeds more than hermaphrodites in S. acaulis, and alternative hypotheses will need to be examined to explain the difference in the performance of the seeds from the two sexual morphs. Key words: Caryophyllaceae; embryo mass; fruit set; gynodioecy; nutrient content; seed mass; Silene acaulis.

Arctic tundra plant species exhibit striking variation in leaf character and growth form. Both are likely related to differences in vessel anatomy, and all may affect responses to climate changes in the Arctic. To investigate the relationships among leaf character, growth form, vessel anatomy, and susceptibility to freeze-thaw-induced xylem cavitation, xylem vessel characteristics were compared among six deciduous and six evergreen arctic dicot species of erect and prostrate growth forms. We hypothesized that deciduous and erect species would have larger and longer vessels than evergreen and cushion/mat-forming species. Vessel lengths, diameters, and densities were measured for each species. Theoretical vessel flow rates were calculated using Poiseuille's law for ideal capillaries. Flow rates were used to determine the susceptibility of vessels to cavitation induced by freeze-thaw events that may become more frequent with global warming. Vessel diameters were larger in deciduous species compared to evergreens, and in shrubs/trees vs. cushion/mat-forming plants. Vessel length distributions, however, did not differ for growth form or leaf character. Vessel density was greater in cushion/mat-forming species than in shrub/tree species. Deciduous plants showed a greater contribution to total conductivity by relatively larger vessels than evergreens. One of the deciduous species, Vaccinium uliginosum, is predicted to be susceptible to freeze-thaw-induced cavitation. These results have important implications for future arctic species composition and plant community structure. Key words: cavitation; cushion plant; tundra; vessel density; vessel length.

Buxaceae are a small eudicot family of mostly monoecious evergreen shrubs and comprise up to five genera (Buxus, Notobuxus, Sarcococca, Pachysandra, Styloceras) and 120 species. Delimination of the family and inter- and intrageneric relationships within the family have been controversial. Sequences of nuclear ITS and plastid ndhF from 25 representatives of Buxaceae were analyzed separately and in combination to resolve phylogenetic relationships among and within genera. Two major clades were identified: the clade of Pachysandra, Sarcococca, and Styloceras and the clade of Buxus and Notobuxus. Pachysandra and Sarcococca were two strongly supported monophyletic groups. The sister relationship of Sarcococca to the clade of Pachysandra and Styloceras is also strongly supported. American and Eurasian Buxus each form a strongly supported clade. The controversial genus Notobuxus is embedded among African members of Buxus. Ongoing morphological studies will improve our understanding of the evolution of morphological characters and phylogenetic relationships of Buxaceae.