• Journal of Korean Society of Forest Science
• /
• v.51 no.1
• /
• pp.22-35
• /
• 1981

This study was designed to know difference in degree of dehardening and rehardening respectively by artificial high and low temperature treatments among different clonal seedlings and seedlings from different seed sources of Cryptomeria japonica which have been grown under the cold areas in Japan and Korea. High temperature treatment was done with 15 to $20^{\circ}C$ under 100% relative humidity for one to nine days and low temperature treatment was carried with $-7^{\circ}C$ for one to three days. Occasionaly, high temperature treatment was combined and followed by low temperature treatment. The ability of stem section to delay dehardening by high temperature treatment and/or to hasten rehardening by low temperature treatment was used as an indicator of adaptability under extreme temperature fluctuation in nature. Clones and seedlings from different seed sources which showed greater freezing resistance than others after artificial high and/or low temperature treatments were selected over two to three time periods: early winter, mid winter and early spring in 1977 to 1980. These were Seoul #7, and #9, Namboo #3, and #4, Sung-Kang #11, Chung-Sam #8 and Huek-Suk #9. These selected seedlings might have survival advantage to withstand early and late frost damage, especially the critical frost damage of the basal stem, since it was known to be induced by lowering freezing resistance of the basal part when exposed to the high temperature near the ground during the day. Large variation in freezing resistance and degree of dehardening and rehardening was found among clonal or seed sources and among individuals within a seed source, but was not related to the difference in climatic conditions where the parent trees was selected. These indicated the possibility of future breeding work for more cold resistant family of Cryptomeria japonica.

• Journal of Korean Society of Forest Science
• /
• v.53 no.1
• /
• pp.27-36
• /
• 1981

Foliar nutrient concentrations of N, P, K, Ca, Mg, total sugar, starch, ether extracts were determined for three Pinus spp., that is, P. rigida, P. taeda, P. rigida${\times}$taeda, divided by tree age (16~19-year old, 6-year old), leaf age (current, over-winter, one-year old), planting location(Kyonggi-Do, Chungnam-Do, Junbuk-Do). Foliar compositions of inorganic nutrients were generally put in order of N(0.764~1.502%)>K((0.130~0.491%) $$\geq_-$$Ca(0.165~0.442%)>Mg(0.054~0.121%)${\fallingdotseq}$P(0.041~0.129%) in all the species. The concentrations of total sugar and ether extracts respectively ranged from 5 to 15% of the needles in dry weight base. The concentrations of N, P and K were similarly high in the over-winter needles (sampled in February), but those of Ca were generally high in one-year old needles. As a whole, inorganic nutrient levels in the needles showed different patterns with species, three age, leaf age and location. There were generally positive correlations between nitrogen and phosphorus in foliar concentrations. Foliar concentrations of total sugar showed the ranking of P. rigida > P. rigida${\times}$taeda > P. taeda and the lowest levels in February. Starch in the needles were contained about 10% of total sugar, and the variations of starch level were not regular with the studied factors. Ether extracts contents increased more of less with leaf age but changed irregularly with the other factors.

• Journal of Korean Society of Forest Science
• /
• v.51 no.1
• /
• pp.1-21
• /
• 1981

Populus glandulosa and Populus tomentiglandulosa, which were known to be natural hybrids, were examined for morphological, physiological and karyological traits to illucidate its hybridity and taxonomical importance. The results abtained were as follows; 1. Survival rate in rooting of cuttings and grafting was different between the hybrids and their rooting abilities showed incomplete dominance. 2. Their leaf openings showed incomplete dominance. The leaf longevities of P. alba ${\times}$ glandulosa and P. tomentiglandulosa were stronger than the other hybrids. 3. There were differences in resistance to toxicity of $KClO_3$ between the hybrids. 4. Many external leaf characters of the hybrids also showed incomplete dominance. P. tomentiglandulosa was similar in those characters to P. alba ${\times}$ glandulosa while P. glandulosa was similar to hybrids crossed, reciprocally crossed or back-crossed between P. davidiana and P. alba. 5. Their numbers of male flower showed incomplete dominance or hybrid vigor. The numbers of P. tomentiglandulosa were similar to thosa of P. alba ${\times}$ glandulosa while those of P. glandulosa to those of P. alba ${\times}$ davidiana or P. davidiana ${\times}$ alba. 6. Morphology and band color of male catkin bract showed incomplete dominance. Those of P. glandulosa were similar to those of P. alba ${\times}$ davidiana while those of P. tomentiglandulosa to those of. P. alba ${\times}$ glandulosa. 7. There were differences in vascular bundle number and arrangement of petiole between the hybrids. 8. Differences in the anatomical traits of stem did not exist between the hybrids but those in wood fiber size existed. 9. The chromosomes of artificial hybrids, P. glandulosa and P. tomentiglandulosa showed irregular behavior in metaphase I and II. 10. All hybrids including P. glandulosa and P. tomentiglandulosa showed small number of P.M.C. with 19 II but many univalent chromosomes were exhibited in metaphase I. 11. All hybrids including P. glandulosa and P. tomentiglandulosa showed a little abnormal nuclear plates as laggard chromosome and chromosome bridge in anaphase I and II. 12. The frequency of pollen tetrad and fertile pollen was low in most of the hybrids including P. glandulosa and P. tomentiglandulosa.

• Journal of Korean Society of Forest Science
• /
• v.53 no.1
• /
• pp.44-55
• /
• 1981

Neutral sulfite precooked fir chips were refined in the Asplund Laboratory Defibrator at various temperature ($20^{\circ}C$, $120^{\circ}C$ and $180^{\circ}C$). The effects of refining temperatures on the physical property and morphological structure of the resulting pulps were discussed. Yields of precooked chips (84%, 92% and 100%) and refining temperature affected remarkably the yield of refined pulp, its beatability, sheet strength and morhphological characteristics. Pulp yield and beatability decreased with increasing refining temperature. Fiber surface of unbeaten pulp from precooked chips of 84% yield was to some extent covered by the secondary wall, while that of the pulp form precooked yield of 92% by the compound middle lamella. In the case of uncooked chips, fibers were damaged heavily, and the exposed fiber surface resulted from the equal amount of the secondary wall and the compound middle lamella. In the case of pulps prepared from precooked chips of higher yields (92% and 100%), sheet strength increased linearly as sheet density increased. But at the same sheet density, pulp from lower precooked yield (84%) had better sheet strength after open discharge refining as compared to pressurized refining, because pulp from the former had much amounts of fines fraction of higher water retention value than the latters. And there was observed a little difference in fiber length distribution but nearly similar in its morphology with increasing refining temperature.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.45 no.4
• /
• pp.619-624
• /
• 2016

Chlorine dioxide ($ClO_2$) gas treatment (75 ppmv, 30 min) has been suggested to improve the microbial safety of postharvest paprika in a previous study. Based on these results, in this study, an additional combined treatment using low-concentration $ClO_2$ gas-generating sticks (3 ppmv) in paprika samples during storage was carried out at $8^{\circ}C$ and 90% relative humidity to further enhance the quality and reduce the decay rate of paprika for the purpose of lengthy storage. After the combined treatment, the initial populations of total aerobic bacteria as well as yeast and molds in the paprika samples decreased by 3.04 and 2.70 log CFU/g, respectively, compared with those of the control samples, and this microbial inactivation was maintained by the low-concentration $ClO_2$ gas-generating sticks during storage. In particular, the decay rate of samples with combined treatment was significantly lower than that of the control. Vitamin C content, hardness, and color quality parameters of paprika samples were not altered by treatment, while weight loss of the samples treated with the combined $ClO_2$ gas was lower than that of the control during storage. These results indicate that the combination of two different $ClO_2$ gas treatments is effective for retaining the quality of paprika during prolonged storage.

• Journal of Korean Society of Forest Science
• /
• v.80 no.2
• /
• pp.151-161
• /
• 1991

I tried to specify the taxa of Fagaceae in Korea by the character of their pollen grains. The light microscope(LM) and the Scanning electron microscope(SEM) were used to examine the pollen grains of 19 taxa, 5 genera. The result are as follows. 1. The pollen of Fagaceae in Korea could be grouped into four types and 4 subtypes. 1) Fagus type 2) Castanea type 3) Lithocarpus, Castanopsis type 4) Quercus type (1) Cyclobalanopsis subtype (2) Prinus subtype (3) Dentatae subtype (4) Cerris subtype. 2. The morphology of the granula on the pollen of Quercus was closely related to the differantiation of the shape of the cup scales. 1) The uniformity of branching granula on the pollen grain surface corresponds to the morphological features of the concentric arrangement of cup scales. 2) The morphological features of the pollen grain surface intermingled with large or small granula, simple-granula and tuber granula which have small points of circular prominence, corresponded to those of short cup scales. 3) The morphological features of the polllen grain surface intermingled with large or small granula, simple-granula and tuber granula with an apex of amoeba type corresponded to those of Q. dentata Thunb, with thin, fine and long cup scales. 4) The morphological features of the pollen grain surface intermingled with large of small granula of with only simple-granula, corresponded to those of Q. acutissima carr. with thick, fine and long cup scales. 3. The result of cluster analysis by coding the sculpture pattern of the pollen grain surface, the existence and nonexistence of surface perforate, the grain size and granula type were coincident with the system of classification of plants and showed an intimated relationship even under th level of species.

• Journal of Korean Society of Forest Science
• /
• v.68 no.1
• /
• pp.60-68
• /
• 1985

To study the comparison of the aboveground biomass of Robinia pseudoacacia L. of 8-, 13- and 20-year-old plantations, the experimental plot of $100m^2$ in size located in Youngin-gun were selected. Seven sample trees at different stand ages selected taking account of DBH distribution were felled and the diagram of oven-dry weight distribution of stem, branch and leaf for each 1m segment was constructed. The dry weight of each part of plots was estimated by the method of basal area ratio. If the estimations are extended to a hectare area stand, it contains 36.72, 69.28 and 118.67 tons of the aboveground standing crops in 8-, 13- and 20- year-old stand respectively. The net production was estimated to be as much as 12.56, 13.23 and 16.78 tons per hectare per year and the net assimilation ratio 3.66, 4.13 and 2.50 kg/kg/yr in 8-, 13- and 20-year-old stand respectively. And the efficiency of leaves to produce stem was 1.69, 2.10 and 0.96 kg/kg/yr in same order.

• Journal of Korean Society of Forest Science
• /
• v.77 no.1
• /
• pp.43-52
• /
• 1988

One-year-old seedlings of Ginkgo biloba were treated with various simulated acid rains(pH 2.0, pH 3.0, pH 9.0 and pH 5.0) to examine the effects of simulated acid rain on the chemical properties of the tested soil. The seedlings were grown in a pot($4500cm^3$)containing one of three different soils(nursery soil, mixed soil and sandy soil). Simulated acid rain was made by diluting sulfuric and nitric acid solution($H^1SO^4$ : $HNO^3$ =3 : 1, V/V) with tap water and tap water(pH 6.4), and treated by 5mm each time for three minutes during the growing seasons(April to October 1985). Acid rain treatments were done three times per week to potted seedlings by spraying the solutions. The chemical properties of potting media were compared among three soil types as well as among the various pH levels. The results obtained in this study were as follows : 1. Exchangeable calcium and magnesium contents and base saturation of the soil decreased with decreasing pH levels of acid rain, and their decreasing rates were as follows : sandy soil was the highest, followed by mixed and nursery soils, However, exchangeable aluminum content rather increased as the pH levels decreased. 2. Available phosphate in the soil decreased as the pH levels of acid rain decreased. Its content increased in nursery soil, compared with those before acid gain treatment, Gut decreased in mined and sandy soils. 3. Soil sulfate and nitrate contents increased remarkably as the pH levels decreased, and the only significant difference in the sulfate was found among the pH levels. Soil sulfate content was the highest in nursery soil, followed by mixed and sandy soils.

• Journal of Korean Society of Forest Science
• /
• v.76 no.2
• /
• pp.99-108
• /
• 1987

Half-sib seeds and one-year-old seedlings of Ginkgo biloba were treated with various simulated acid rains (pH 2.0, pH 3.0, pH 4.0 and pH 5.0) to examine the effects of acid rain on seed germination and seedling growth. The seeds were sown in a pot ($4500cm^3$) containing one of three different soils (nursery soil, mixed soil and sandy soil) and the seedlings were grown in the same pots as the seeds. Simulated acid rain was made by diluting sulfuric and nitric acid solution ($H_2SO_4$: $HNO_3$ = 3:1, V/V) with tap water and tap water (pH6.4), and treated by 5mm each time for three minutes during the growing seasons (April to October 1985 and April to August 1986). Acid rain treatments were done three times per week to potted seeds and seedlings by spraying the solutions. The seed germination, seedling growth and physiological characteristics of potted seedlings were compared among three soil types as well as among the various pH levels. The results obtained in this study were as follows: 1. Seed germination of Ginkgo biloba decreased significantly at pH 2.0 level in the field test, and also at the levels of both pH 2.0 and pH 3.0 in the laboratory test, compared to that at control. 2. For two-year-old seedlings, total, top and root dry weights per seedling were significantly different among the three soil types and among the levels of pH, and shoot growth was different only among the levels of pH. 3. For one-year-old seedlings, height and total and stem-branch dry weights per seedling were significantly different among the levels of pH.

• Journal of Korean Society of Forest Science
• /
• v.80 no.2
• /
• pp.202-209
• /
• 1991

This study was carried out to examine seed germination, seedling growth, and biomass production of Eucommia ulmoides. The results were summarized as follows ; 1. Cold moist stratification at a refrigerator showed 60.3% of seed germination, which is the most effective among pretreatment methods. 2. In case of 1-0 seedlings, sixty seedlings per $1m^2$ was the most appropriate density, and the growth quality of seedlings differed significantly among densities. 3. Height growth showed continuous growth pattern and the maximum growth was shown during the period 21 June to 20 July, which corresponds 32.7% of total annual growth. 4. As tree age and DBH increased, the production of bark and leaf increased, however, its increment rate remarkably dropped down after ten years. 5. When tree age was ten years, the rate of bark volume showed the maximum value, 12.42%. 6. Dry weight of barks and leaves and bark volume were positively related to the growth of DBH and height. 7. As tree age increased, leaf area decreased, but the number of leaves increased.