• Current Research on Agriculture and Life Sciences
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• v.4
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• pp.163-168
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• 1986

This study was carried out to compare the conditions of Korean and Japanese forestry. Two countries were appeared same trend in forestry condition, so our forestry in future can be estimated with compared Japanese forestry, but the results obtained are as follows ; 1) The average forest area per capita of the world, Japan and Korea are 0.9, 0.23 and 0.16 ha, respectively, this means that Korean forest area is not sufficient. The growing stock of forest per capita is $22.5m^3$ in Japan and $3.9m^3$ in Korea, but timber consumptions per capita are $1m^3$ in Japan and $0.2m^3$ in Korea. Those mean that both countries have not a plentiful resource of forestry. 2) The forestry production activity becomes gradually stagnation. Both in Korea and Japan, the reforestation and stumpage felling area show gradually decreasing tendency, the artificial forest ratio of total forest area is, at present, 28% in Korea and 40% in Japan. 3) In forestry demand aspect, the ratio of imported timber is 79% in Korea and 62.4% in Japan. Because the price index of timber is lower than the general price index, the dullness of forestry-related industries is expected in future. 4) The forestry labour supply has gradually difficulty because of the reduction in farming labour. 5) The managements of national forests show deficit operation, at present, both in Korea and Japan. The results above mentioned are derived form the poor forest resources, therefore, it is considered that rather more and continuous investment is necessary, but also forestry should be invested in the territorial conservation aspect.

• Current Research on Agriculture and Life Sciences
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• v.5
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• pp.112-118
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• 1987

This experiment was conducted to obtain the basic information for the effective control of rice blast. Eleven races of Pyricuiaria oryzae were identified, 5 races of KJ group and 6 races of KI group in Kyungpook province. Among them KJ301 was the most dominant one, and they were prevailed in the order of KJ401, KJ201, KJ101, KJ105, KI307 and $KI315^b$. The distribution ratio of KI group race was higher in the middle and northern region than the southern and coastal region. A positive correlation was found between the distribution ratio of KI group races and cultivated area of indica type cultivals. The total ratio of Blasticidin-S resistant isolates in P. oryzae was 31.2%. The distribution ratios of resistant isolates were 43.2% in the southern region, 29.4% middle, 25.0% nothern and 10.5% coastal region, respectively. The distribution ratio of Blasticidin-S resistant Isolates was correlated positively with amounts of the chemical sprayed, but not correlated with the race of P. oryzae.

• Current Research on Agriculture and Life Sciences
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• v.2
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• pp.15-22
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• 1984

This study was conducted to identify the enzyme treatment time, enzyme concentration and plant growth condition for isolation of potato mesopyll, it was also performed to determine the adquate sucrose molarity on purification of protoplasts and to investigate the incubation time, PEG concentration and DMSO effect for potato-petunia protoplast fusion. The results were summarized as follows: The optimal time of incubation in enzyme solution was 3 - 4 hours and high humidity and low light intensity made plants more effective to protoplast releasing enzymes. Our experimental results showed that the pectolyase Y-23 was an ideal agent for isolation from mesophyll cultured in vitro compared with macerozyme. The enzyme solution with 0.5 % macerozyme and 2 % cellulase was very effective and the purity of healthy protoplast was better in 0.4 and 0.5 M sucrose than in others. It was revealed that the rate of potato-petunia fusion according to the incubation time with PEG was effective at 30 min incubation and percentage of protoplast aggregation was increased by high molecular weight and concentration of PEG. Percentage of potato-petunia protoplast heteroplasmic aggregation was increased by 4 to 16 % in PEG 6000 compared with PEG 4000 and PEG 1500. Addition of 5 to 10 % DMSO to the PEG solution increased to the heteroplasmic aggregation of potato-petunia from 2 to 4 %.

• Current Research on Agriculture and Life Sciences
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• v.5
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• pp.106-111
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• 1987

The susceptibility of 8 chrysanthemum varieties to Apelenchoides ritzemabosi, Shuhonothikara and Sagakiku were resistant by 11.7% and 14.5% each infested leaf, Sinrokusiogio, Dangonanako and Sintoa were susceptible as above 50%, Gold wave and Tenju were modertae by 24 to 26%. Percentage of infested leaf was positively correlated with the number of epidermal hair but not with leaf area, leaf thickness, stomatal size, number of stomata and length of epidermal hair. In effect of watering method, Polyethylene film cover plot was lowest by 9.4%, next conventional watering plot by 50%, Conventional watering and spray plot was the highest by 62%. The infested leaf rate was closely related with a number of rainy days than the amount of rainfall. Effect of chemical soil treatment, Temik showed the lowest infested leaf rate by 5%. There was no significant difference between the chemicals except Temik, but these are markedly effective in compare to control.

• Current Research on Agriculture and Life Sciences
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• v.2
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• pp.23-28
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• 1984

From November 5th to December 5th in 1984. this study was carried out to find the effects of the prechilling and predrying treatment on the germination rate, the plant rate, the plant height, and the seedling growth rate in some varieties of barley and malting barley. The result obtained were as follows: In germination rate, barley varieties were the highest at the prechilling treatments for five and eight days and malting barley varieties were the highest at the prechilling treatment for eight days. In predrying, the seven days' treatment revealed higher germination rate than other in all varieties except Sacheon-6, Sacheon-6 showed the highest rate at the five days treatment. The growth rate in all varieties was the greatest at the prechilling treatments for five and eight days. In predrying treatments, the growth rate in Oweolbori and Hyangmaek was more effective at the predrying for three days, in Sacheon-6 for five days, and in Albori for seven days, respectively. The highest plant height was revealed at the prechilling treatment for five days in barley varieties and for eight days in malting barley varieties.

• Current Research on Agriculture and Life Sciences
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• v.4
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• pp.22-26
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• 1986

This study was conducted to investigate weed population dynamic in orchard and to establish an appropriate application time for oxyfluorfen. 28 weed species including Persicaria hydropiper was observed to be problem weeds in orchard. P. hydropiper was on single dominant species which increased importance value of 13.7 on May 15 to 60.79 on August 10, followed by Calystegia hederacea, Alopecurus aequalis, Capsella bursa-pastoris, Roripa islandica, Echinochloa crus-galli, Potulaca olearcea, Elusin indica. Simpson's index increase from 0.11 on May 1 to 0.40 of August 10, indicating the dominance of specific weed species. The effective herbicide to control these weeds was oxyfluorfen at 5kg prod./ha applied at pereemergence treatment on March 25, showing more than 90% control for 120 days after application. Preemergence application of oxyfluorfen at 3kg prod./ha on March 25 followed by paraquat 3kg prod./ha applied on June 25 as the foliar application can maintain the clean orchard for a year, showing on of the promising and applicable control system. The most appropriate rate and time for oxyfluorfen seemed to be 5kg prod./ha applied on March 25.

• Current Research on Agriculture and Life Sciences
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• v.5
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• pp.100-105
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• 1987

To study the relative effectiveness of the antioxidants (BHA, BHT) and the transparent cellophane films (colorless, blue and red) on rancidity development of the sesame oils treated with sunlight - irradiation condition, this experiment was carried out. The results obtained as follows ; 1. The retarding effect of the antioxidants on POV, COV and TBA development was more effective than control, and Bill was more effective than BHA. 2. The transparent cellophane films were more effective than antioxidants, and red was more effective than blue transparent cellophane film. 3. During the storage of the sesame oils which were covered with colorless, blue and red thansparent cellophane film respectively, the contents of linoleic acid in sesame oil were decreased, while oleic acid were increased.

• Current Research on Agriculture and Life Sciences
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• v.2
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• pp.29-33
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• 1984

From June 28th to July 17th in 1985, this study was performed to obtain the information of the fresh corn forage production through the spraying hydrophonics in summer. The experiments were conducted in vinyl house on Kyungpook University's Experimental Station. The results obtained were as follows: It was suggested that the treatment of soaking for 24 hrs and followed by the pretreatment for 48 hrs was better than other treatments. Seed cost for the production of 1 kg fresh forage was the most inexpensive at the seeding rate of 450 g per $30{\times}60cm$ tray than other seeding rates. Application of 1000 times diluted Hyponex solution (1000X Hyponex) or 300 times diluted Yogen solution (300X Yogen) one time per day resulted in the heavier fresh weight than the other treatments. Treatments of 300X Yogen and 500X Yogen gave the better fresh weight in one application per two days and per three days, respectively. But, this method was not useful in summer because the lowest seed cost for the production 1kg fresh forage was 73Won, and collection of the fresh forage from the mountain range was easy.

• Current Research on Agriculture and Life Sciences
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• v.4
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• pp.18-21
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• 1986

This study was conducted to clarify the period of induction and awakening of Liatris spicata corm dormancy, and investigated effect of gibberellin treatment on the dormancy break of corm. The results were obtained as follows ; 1. Ratio of sprouting, shooting and rooting were gradually declined after August 30. These ratio showed the lowest to trend on November 14 during experiment and gradually increased after this time. Ratio were excellent as 100% after January 29. 2. Also, average days for sprouting were the longest on the November 14, but it was rapidly declined after January 29. 3. The period of induction and awakening of corm dormancy were late in September and from late January to early February, respectively, in Daegu, Korea. 4. Effects of GA-treatment on the dormancy break of corm were excellent. Especially, its effects on the dormancy break were the deeper in degree of dormancy, the better.

• Current Research on Agriculture and Life Sciences
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• v.4
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• pp.12-17
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• 1986

Six genetic populations, viz, $P_1$, $P_2$, $F_1$, $F_2$, $B_1$, and $B_2$ of three crosses involving five varieties ($342{\times}$Kimjanggochu, Masan${\times}$Hungarian was, and Masan${\times}$Jeju) were used for estimating heterosis, heterobeltiosis, inbreeding depression, genetic components, heritability and correlations for fresh and dry anatomical components of red pepper. The results obtained were summarized as follows. Heterosis was positive in most characters of three crosses and heterobeltiosis was negative except in cross $342{\times}$Kimjanggochu. Inbreeding depression was positive, showing decrease of weight in $F_2$ generation. Duplicate and complimentary type of epistasis were concerned with the expression of characters, and broad and narrow sense heritabilities of fruit weight and pericarp weight were fairly high and stem weight, placenta weight and seed weight were low. Correlations among the anatomical components were positively significant in fresh and dry weights.