| Chinese fir is a timber tree, in widely cultivated areas, hardy, a fast-growing tree species; yellow-white wood, sometimes heartwood with reddish-brown, soft, meticulous, perfumed, texture straight, easy processing, corrosion-resistant and strong, termite cannot eat, used in bridges, ship building, pillar, stakes, poles, furniture and wood fiber raw materials in industrial. Vietnamese Chinese fir forest plantations area is increasing day by day but there is not a good quality of Chinese fir seeds and seedlings which the mountain people harvested from natural forests. After sowing from seedling to planting Chinese fir forest plantations have very slow growth, poor quality and low economic value. Because the selection of Chinese fir provenances is very important to promote area of Chinese fir forest plantation in Vietnam, to get good quality seedling, wood, high cost and increase the income of people planting forest,In view of this, use Chinese fir provenances in 9 districts in the Northern of Vietnam (tobe called 9 provenances) to select good mother trees for seeds collection, and sowing in the nursery in Lang Son province where natural conditions are typical in the North of Vietnam are estimated and compared on the growth of Chinese fir provenances seedlings. Use 9 Vietnam Chinese fir provenances and 1 China Fujian Chinese fir provenance FS09 (which has suitable climatic conditions as Guangxi province climate) for planted forest trial in 3 areas:Northern, Central and Southern Vietnam. We then analyzed and compared soil and foliar nutrients of of all ten provenances in three trial areas; then analyzed and compared chlorophyll fluorescence, chlorophyll content and leaf structure. The main results are:1. The study on 1000 seeds weight and germination rate of seeds in Vietnamese Chinese fir provenances, the result showed that the average 1000 seeds weight of provenances in 7.440 g-9.784 g and the average germination rate of provenances was 47.82%-65.64%, the highest germination rate was in provenance CL8. The 1000 seeds weight and germination rate, root length and germination were related; the heavier seeds had higher germination rates, and longer roots. Seed germination rate Y(%) can be determined through 1000 seeds weight X(g) by using the equation Y= 4.8458+5.7848·X(R> 0.835; P<0.01).2. Seedling growth in the nursery showed that the CL2, CL7, CL3, CL6, CL1, CL9 and CL8 provenances had an average ground diameter of 0.18 cm and seedling height 19.82 cm. These were the most suitable for growth in the experimental area.3. The growth study of provenances over 30 months in three experimental sites in Vietnam showed that the natural conditions of Liangshan province in the North of Vietnam is the most suitable area for the growth of Chinese fir. In the North, CL9, CL2, CL7, and CL1 (group average diameter 5.93 cm, height 283.07 cm, canopy diameter 155.40 cm) were the fastest growing groups. In the Central site the CL4 provenance was the most suitable (average diameter 1.38 cm, height 77.29 cm, canopy diameter 60.57 cm); and in the South the CL9, CL8 and CL2 groups (group average diameter, tree height and canopy diameter were 2.57 cm.122.19 cm, 78.76 cm) were the most suitable. In north of Vietnam, Chinese fir sampling growing better than in Southern and Central of Vietnam.4. The growth of most Chinese fir provenance sapling and seedling was positively correlated which were fast growing in the nursery stage were stronger later, and also better able to withstand stress conditions, but there are some provenances saplings and seedling grow was not the same.5. Chinese fir in its annual growth, their growth have different potential in different seasons, under which the Chinese fir saplings grow into four growth periods:early period growth, growing period, late period growth and dormant period. In which growing period and late period growth were high photosynthetic capacity. In the same time, there were significant differences in photosynthetic chlorophyll content and photosynthetic capacity of different provenances. The photosynthesis and growth rate of Chinese fir provenances were correlated. Chinese fir provenances with high chlorophyll contents and photosynthetic capacity were both faster growing.6. Leaf structure microscopy showed that the average length of the leaf blade was 42.90 ± 7.33 mm and the longest was 48.46 mm; average leaf width was 2.81 ± 0.36 mm, with a maximum width of 3.02 mm. Provenances with fast growth had shorter, wider leaves with intermediate leaf area. Microstructure analysis showed that thick leaves, palisade tissue thickness, vascular bundle thickness, width of vascular bundles, xylem thickness, xylem width and phloem thickness were not closely related to provenance. All leaves had one large resin duct in the middle; with the exception of provenances CL7 and CL9 which not only had one large resin duct in middle but also had two small resin ducts on both sides of leaves. The average stoma density was 215.87 ± 19.63 stomata ± mm2, the average stoma length was 43.36 ± 4.25 ?m, the average stoma width was 26.30 ± 2.82 ?m, and the average stoma length and width ratio was 1.65. Provenances with fast growth and longer and wider stomata also had high stomatal density, conversely provenance with a slower growth have smaller stoma width and length and lower stomatal density.7. Chinese fir provenances are suitable living in northern Vietnam, with elevation more than 100 m above sea level, thick soil (> 80cm), sandy soil, with high availability of N, P, K, Ca, Mg, and pH> 4.5. Therefore considered soil conditions in northern Vietnam is conducive to the introduction Chinese fir of work. Chinese fir is not suitable however in windy, dry conditions with clay soil.8. The study compared nutrients across Chinese fir provenance leaves and trial site soil; the results showed that the average nutrient content in Chinese fir leaves were higher than soil samples in the northern areas. The average nutrient content in northern leaf samples were 26.46-314.64 times higher than in soil samples, this ratio in the central area was 13.85-811.77 times and 2.01-302.82 times in the south of Vietnam.30-month-old Chinese fir saplings absorb, in descending order, nitrogen, potassium, phosphorus, calcium and magnesium. In the growth stage of saplings, trees need to use more nitrogen to promote growth height, diameter, and leaf production; as well as potassium and phosphorus, which help in photosynthesis and the production of healthy seedlings.9. In the same trial site, Chinese fir provenances which grew faster due to higher NPK contents in leaves; provenances CL9, CL7, CL1, CL2 grew fastest in growing area with in respect to nitrogen, phosphorus, potassium (Kali), calcium, magnesium contents average ratio in leaves:1.00:0.09:0.51:0.07:0.03, respectively.10. Research on evaluation and early selection good Vietnam Chinese fir provenances showed that:In northern Vietnam CL9, CL2, CL7 and CL1 were excellent provenances; CL8, CL3, CL6 and CL4 were general provenances, unsuitable provenance was CL5 provenance. In central Vietnam, CL4 was excellent provenance; general provenances were CL6, CL7, CL2, CL9, CL1 and CL3, unsuitable provenances were CL8 and CL5. In the south of Vetnam, CL8, CL9, CL2 were excellent provenances, generally provenance include CL3, CL1 and CL7 provenance, not suitable were CL6, CL4 and CL5 provenances.11. Comparison on the study results of China and Vietnam Chinese fir, resuilt showed that: (1) Vietnamese Chinese fir seed was heavier than China's, germination rate was higher than the results of Chinese studies, the studies results of two national had showed that:seed weight and seed germination rate in closely, most provenances seed weight are heavier, the germination rate are higher. (2) In nursery stage,6 months China Chinese-fir provenance seedling were growing faster than Vietnam's, Vietnam Chinese fir seedlings average height 18.94 cm and 0.17 cm average diameter; respectively, the average height and diameter of China Chinese-fir provenance seedlings were 19.72 cm and 0.38 cm. (3) Photosynthetic efficiency of China Chinese-fir leaves was higher than that of Vietnam, while China Chinese-fir heat dissipation capacity was smaller. Total chlorophyll (a+b) in China Chinese-fir leaf was higher than that of Vietnam, It showed that China Chinese-fir has a high photosynthetic capacity; but Vietnamese Chinese fir leaves chlorophyll (a/b) values was higher than China's, showed that Vietnam Chinese-fir positive with the light than China's. (4) Chinese fir leaf length and width had varies greatly, the amplitude of length and width of China Chinese-fir leaves was larger than Vietnam's, Vietnam, In which, Vietnam Chinese-fir leaves were longer than China's, but leaves width were smaller than China's. China Chinese-fir leaf thickness, leaf thick-skinned, leaf mechanical thick, vascular bundles thick, Vascular bundle width and resin duct diameter of 1.10 to 1.64 times larger than that of Vietnam Chinese-fir leaves. (5) The growth of 2.5 year-old Chinese Chinese fir tree height, ground diameter and crown width were faster than those of Vietnam; CL9 and CL2 were the fastest growing of Vietnam Chinese-fir provenances, they can grow the same with China Chinese-fir provenances in comparison. |
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