Comparative leaf anatomy of some species of Abies and Picea (Pinaceae)

Abstract

A number of conifer species are still lacking anatomical data, which is significant because morphological and anatomical data are essential for systematic study. Leaf anatomy was studied in selected species of Abies and Picea using light and scanning electron microscopy. Both genera were found to have typical coniferous and highly xerophytic leaves with sunken stomata and an epidermis covered by a thick cuticle. In the genus Abies, species can be differentiated by the nature of the lignified hypodermis and the number and position of resin ducts. Abies firma and A. holophylla have a continuous hypodermis whereas in A. koreana and A. nephrolepis the hypodermis is discontinuous and represented by isolated cells or groups of four or five cells. On the other hand, in Picea leaf shape, stomata arrangement, and number, position, and nature of resin ducts are the key features for species differentiation. Picea jezoensis has a flattened leaf with stomata distributed on the adaxial surface whereas P. abies and P. koraiensis have a rectangular leaf with stomata found on surfaces.

Physical Properties of Seeds of Eleven Fir Species

“…They thrive in temperate and cool climates at altitudes not exceeding 4700 m above sea level. Firs are distributed mainly in North America (9 species), Central America (6 species), Siberia and Eastern Asia (17 species), the Mediterranean Region and the adjacent areas (8 species) [1][2][3][4][5][6][7].…”

Physical Properties of Seeds of Eleven Spruce Species

“…Depending on species, spruces reach the height of 20 m to nearly 100 m at full maturity [1,2]. Approximately 40 spruce species have been identified to date, and all of them reside in the northern hemisphere [1,[3][4][5][6][7]. Spruces are the predominant tree species in extensive boreal forests [8][9][10][11][12].…”

New fossil Pinaceae from the Early Cretaceous of Mongolia

“…The overall shape of the ovuliferous scales with rounded, erose, and emarginate apexes, the absence of an apophysis (umbo), the minutely and proximally toothed margin of the cone scales, an interseminal ridge that extends no more than half the height of the seed body, and seeds that are held in shallow cups and are almost to fully covered by wing tissue on the exposed side of the seeds only, are features that in combination also support an affinity with extant Picea (Table 1). The helically arranged, flattened leaves of P. farjonii, with epistomatic stomata and peg-like bases without twisted pulvini, are also consistent with a relationship to Picea (Table 1; Farjon 1990Farjon , 2010Ghimire et al 2015). Some of these characters do occur in other genera of Pinaceae, but this combination of morphological features is unique to Picea.…”

“…Comparative data for extant Pinaceae (Table 1) were also obtained from descriptions in Pant and Basu (1977), Hu and Wang (1984), Alvin (1988), Frankis (1988), Crabtree and Miller (1989), Farjon (1990Farjon ( , 2005Farjon ( , 2010, Page (1990), Mente and Brack-Hanes (1992), Miller and Ping (1994), LePage and Basinger (1995), Takaso and Owens (1995), LePage (2001LePage ( , 2003, Stockey (2001, 2002), Aizawa and Kaji (2006), Gernandt et al (2011), Klymiuk and Stockey (2012), Rothwell et al (2012), Dörken and Nimsch (2014), and Ghimire et al (2015).…”