| 1. In the leaves of Cedrus deodara, two lateral resin canals appear in mesophyll, distributing on both sides of vascular bundles and adhered to cortex. There are two layer cells around the resin cavity: epithelial cells and sheath cells.2.From the experiment on eduction and tranparency of the whole leaves collected from different positions and ages in Cedrus deodara, we can see obviously that the figure of each resin canal of leaves has little variety. The leaves are mostly claviform and have the same size from up to down while some become thin at the top of the needles. The results show that the anatomy characters of resin canals are stable in Cedrus deodara, which are of great importance in classification.3.The resin canals in leaves are examined in 10 genera and 103 species of Pinaceae. Except Pinus, The number and position of resin canals in leaves of the other nine genera are heritable stably. Resin canals exsit in woods of Pinus, Larix, Keteleeria, Pseudotsuga, Cathaya, Picea, Cedrus and most Tsuga, not in woods of Pseudolarix. In Abies, the related data of two species haven't been collected yet, while among the other 18 species, five species have resin canals and thirteen species haven't. The result of the experiment of this dissertation show that it is very heritable that the leaves of Cedrus deodar have two lateral resin canals. The slices of mature woods, branches and seedling (three years old) show that the occurrence of resin canals is not accassional but frequenty. Then evidently, the presense of resin canals isn't leaded by the haphazard wounding but is determined by the stable genetic factors.4.From the calculating result of 2 test for independence based on the statistical data, we know that there is relevance between the appearance of leaves and woods in Pinaceae. It also prove ulteriorly that resin ducts of woods don't appear accidentally but with high stability and pertinency. Consequently, resin canals are inevitability determined by the stable genetic factors and are relatively steady.they can be passed down, but cannot be changed or induced by the exoteric factors. Resin canals are taxonomicly important because they are of diagnostic value in Pinaceae.5.The result of the experiment also indicate that from the base upward the content aether extractives increase to height 5.3m then decrease gradually. Radial and tangential diameter of resin canals of the wood in Cedrus deodar negtively related to the aether extractives in longitudinal direction. The axial variance of tissue percentage of resin canals and aether extractives are coherent in Cedrus deodar, and there are positive relations between them.6.No more expetiation here as the monograph about Pinus dabeshanensis and its resin canals in leaves has been published in 1999 by my advisor. The axial variance rule of radial diameter of resin canals of the wood in Pinus dabeshanensis is that they increase from base upward. The axial variance rule of tangential diameter of resin canals is that they increase firstly and then decrease from base upward, and the figure is at close quarters.Nowadays, the boundary between normal resin canals and traumatic resin canals is not clearly in the field of traditional theory. The definition of traumatic resin canals is vague, ambiguous and maybe erroneous. In traditional theory traumatic resin canals are arisen by wounding or injury, and it is a kind of protective reaction to the outside stimulation. Nowadays there is no ultimate conclusion of traumatic resin canal's definition. Some ambiguous words are used in the definition, such as "maybe", "perhaps", "possible" and so on. Those words and expressions cannot be used to describe the origin and formation of those traumatic resin canals, and therefore we can't distinguish the normal resin canals from traumatic resin canals during learning and study.In this paper, resin canals of leaves in Cedrus deodar, seedling (three years old), mature wood and branches have been discussed. The results show that resin canals are visual in the all p... |
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