Earticle

본 실험은 식물조직배양 기법을 통하여 한란과 심비디움의 효율적인 증식을 위한 식물 생장조절물질의 적정 처리방법을 구명하고자 수행하였다. 한란의 rhizome 형성은 무처리 및 10 ppm kinetin + 2 ppm NAA, 심비디움의 protocorm 형성은 무처리 및 10 ppm kinetin + 0.05 ppm NAA에서 아주 양호하였다. Callus 유도의 적정 식물 생장조절물질의 농도는 구명하지 못했다. 한란 rhizome으로부터의 shoot 분화에는 10 ppm BA + 2 ppm NAA, 5 ppm BA + 2ppm NAA, 심비디움 protocorm으로부터의 shoot 분화는 10 ppm Kinetin + 0.05 ppm NAA, 1 ppm Kinetin + 2 ppm NAA에서 비교적 효과적인 것으로 나타났다.

This study was carried out to determine the effects of plant growth regulators on organogenesis from Cymbidium kanran and Cymbidium hybrida. Optimal rhizome formation from Cymbidium kanran was obtained on MS medium with 10 ppm kinetin+2 ppm NAA. and optimal protocorm formation from Cymbidium hybrida was obtained on MS medium with 10 ppm kinetin+0.05 ppm NAA. However, in this study the optimal media for the callus induction from both explants was not identified. Optimal shoot induction from rhizome of Cymbidium kanran was obtained on MS medium with 10 ppm BA+2 ppm NAA and 5 ppm BA+2 ppm NAA. Optimal shoot induction from protocorm of Cymbidium hybrida was obtained on MS medium with 10 ppm kinetin+2 ppm NAA.

풋마름병과 역병에 복합저항성인 계통을 육성하기 위한 노력으로서 앞서 역병 저항성으로 육성한 계통(16-2-3-2 = 역병 저항성 '칼미초', 19-1-3-7-1-1, 19-2-4-5-3-2 = 역병 저항성 '수비초', 김 등, 1996)과 풋마름병 저항성 계통(KC350 = MC 4, KC353 = PBC631)을 교배하여 육성한 와 , 와 세대에 대해 1999년과 2000년에 각각 풋마름병과 역병에 대한 복합저항성을 검정하였다. 풋마름병과 역병에 복합 저항성을 보인 개체를 선발하여 다음 세대의 종자를 채종하였다.

In an effort to breed lines resistant to both bacterial wilt and Phytophthora blight, F5 and BC1F4, and F6 and BC1F5 generations of the crosses between the lines previously bred for resistance to Phytophthora blight ((16-2-2-3-2 = Phytophthora-resistant 'Kalmi', 19-1-3-7-1-1, 19-2-4-5-3-2 = Phytophthora-resistant 'Subi', Kim et al., 1996) and sources of resistance to bacterial wilt (KC350 = MC-4 or KC353 = PBC631, Kim et al., 1998) were evaluated for resistance to both bacterial wilt and to Phytophthora blight in 1999 and in 2000, respectively. Plants which were highly resistant to both bacterial wilt and Phytophthora blight were selected for development of the next generations.

1999년도에는 KC47KCB14, KC220KC268 조합의 및 여교배 집단과 KC47-1KC263(AC2258), KC47-1KCB13-2-1, KC47-1KCB13-4-2 조합의 집단에 대하여 잎점무늬병과 역병을 차례로 접종, 복합저항성 개체를 선발하여 차세대를 육성하였다. 2000년도에는 같은 조합의 및 세대에 대하여 잎점무늬병과 역병에 대한 저항성을 검정하여 복합 저항성인 개체로부터 차세대 종자를 확보하였다. 선발세대의 경과에 따라 두 가지 병에 대한 저항성에서 현저한 진전이 관찰되었다.

populations of the crosses KC47-1 (PI244670) KCB14-2-2-3-2 (PI201234), KC220-1 KC268 and bulk populations of the crosses KC47-1KC263 (AC2258), KC47-1KCB13-2-1 (PI201232), KC47-1KCB13-4-2 (PI201232), either one parent of which was resistant to Phytophthora blight, were tested for both gray leaf spot and Phytophthora blight by serial inoculation with Stemphylium solani or a mixture of S. solani and S. lycopersici, and P. capsici in 1999. In 2000, and lines or populations developed from the respective or selections in the previous year were evaluated for resistance to both diseases. A significant progress in resistance to both diseases was achieved by selection.

콩나물의 색과 향에 변화를 주었을 때의 기호도 변화 양상을 조사하였다. 분홍색의 경우 72%, 빨간색의 경우 60%, 녹색의 경우는 44%가 나쁨 또는 아주 나쁨의 부정적인 반응을 나타내었다. 그러나 노란색의 경우 약 55%가 좋음 또는 아주 좋음으로 나타나 색소 처리 콩나물중 유일하게 긍정적인 반응이 높게 나타났다. 그러나 향 첨가의 경우 땅콩향을 첨가한 콩나물에서 80%, 메론향에서 76%가 좋음 또는 아주 좋음에 응답하였으며, 나쁨 또는 아주 나쁨에 응답한 경우는 20%에 불과한 것으로 나타났다. 색소의 첨가 결과와는 상이한 반응을 나타내었다.

Preferences on the change of color and aroma of soybean sprout was surveyed. Negative response of 'bad' or 'very bad' on pink (72%), red (60%), and green (44%) coloring was obtained. However, yellow coloring showed about 55% of positive response of 'good' or 'very good'. Thus yellow is the only color which received highly positive response among altered-color soybean sprouts. Significantly different result was observed when various aroma was added to soybean sprout. 80% of peanut scent-added soybean sprout and 76% of melon scent-added soybean sprout received positive response of 'good' or 'very good' while only 20% of the response was negative. In conclusion, altering color to yellow and addition of peanut scent or melon scent could increase the general preference of soybean sprout.

A field case study was performed to investigate the effect of shallow ponding in paddy field on irrigation water requirement of direct seeded rice. In addition, an economic analysis was made to see the effect of no-till direct seeded rice on cost reduction. A field study was performed at a 2.1ha paddy field in Kimjae city, Chonbuk province from 1991 to 1999. Various direct seeding methods such as dryland seeding, wetland seeding, and no-till wetland seeding were introduced. Then, cost reductions due to the direct seeding and no-till were calculated. In addition, to investigate the effect of shallow ponding on irrigation water requirement, field measurements such as irrigation water volume, drainage water volume, rainfall depth, and ponding depth, were made at a 40a plot within the same area in 1988 and 1990. The results of the shallow ponding study showed that the irrigation water depth, rainfall, and the drainage depth were 379mm, 458mm, and 448mm in 1988 growing season, and 274mm, 819mm, and 736mm in 1990, respectively. The shallow ponding irrigation method saved irrigation water by about 20% with higher yield compared with the traditional method. The economic analysis showed that won \640,000 per ha can be saved by direct seeding due to no nursery cost, and \1,220,000 per ha due to no-till and no nursery cost. The yields ranged 540 to 640 kg per 10a during the study period with an average of 590kg per 10a. If these cropping techniques with no-till direct seeding and shallow ponding depth for rice cropping prove to be advantageous with further study, they can be adopted for the most of the paddy fields in Korea.

수입된 11개 원원 종을 열대기후인 이집트에서 온도가 다른 와 에서 사육하여 주요 유전 형질에 미치는 영향을 연구하였다. 저온 및 고온 공히 교잡 종의 화용 비율과 견층 비율에는 영향을 주지 않았으나, 고온은 유충기간을 단축시켰고, 저온은 견층 중과 상자 당수견 량을 무겁고 높게 하였다 따라서 원원 종의 육성과정에서는 유충 전령을 저온으로 사육하는 것이 잡종강세를 극대화할 수 있음을 알 수 있었다.

Eleven inbred lines of silkworm, Bombyx mori L. were exposed to two main different temperature (23C and 25C) during the larval period in order to elucidate the effect of the temperature differences on their main characters under the, prevailing in Egyptial agro-climactic conditions. The results show that the temperature differences did not affect significantly the pupation ratio and cocoon shell ratio. However, they affected their larval duration to become shorter with the high temperature treatment () and their cocoon shell weight and cocoon yield per box of silkworm eggs to be higher in the lower temperature(). It was recommended that some inbred lines should be bred at the 23C throughout the whole larval period, particularly in being reared with high nutritional leaves in order to maximize the hybridization of cocoon yields.

벼 자동화 육묘시설에서 파종기별 알맞은 육묘기간을 선정하기 위하여 경상북도 안동, 의성 및 경산지역의 육묘시설에서 파종기와 육묘기간에 따른 묘소질, 육묘일수에 따른 수량구성요소와 수량성, 벼 품종별 묘소질 등을 조사 분석한 결과를 요약하면 다음과 같다. 자동화 육묘시설내에서 파종기가 늦어지고 육묘기간이 길어질수록 묘초장 신장 속도는 빨랐고, 지상부 건물중은 증가하였으나, 지상부건물 중/초장 비는 감소하였으며 그 감소폭은 10일묘 이후에서 컸다. 묘초장과 묘소질을 근거로 한 각 지역별 파종기에 따른 적정 육묘기간은 4월 하순 파종의 경우 안동과 의성에서는 15~20일묘, 경산은 15 일묘이고, 5월 하순과 6월 파종의 경우는 지역에 관계없이 10일묘가 적합하였다. 육묘 기간에 따른 수량성은 육묘일수가 10일에서 20일로 연장될수록 감소하였는데, 10일묘의 10 a당 수량은 관행중묘에 비해 5% 증수되었지만 20일묘의 경우는 9% 감소되었다. '대산벼'외 12품종을 대상으로 자동화 육묘시설에서의 묘생육을 비교한 바, 10일묘의 초장은 '상미벼', '원황벼' 및 '일품벼'는 13.3~13.5 cm로 짧은데 비해 '만안벼', '화영벼', '대산벼' 및 '일미벼'는 16.6~17.5 cm로 걸었는데, 이들 품종중 '화영벼'와 '대산벼'는 10일묘의 지상부 건툴 중도 9.1~9.4 mg으로 무겁고 육묘일수에 따른 지상부건물중/초장 비의 감소 폭도 작았다.

Seedling characteristics of rice sowed at different sowing date in an automatic facility were studied at different days after sowing (DAS). The objective was to determine the optimum sowing date and age of rice seedlings at three locations in the Kyongbuk Province of Korea viz, Andong, Euisung and Kyongsan. Heigbt and shoot dry weight of rice seedlings increased from 10 to 20 DAS and with a delay in sowing time from April to June. In these intervals shoot dry weight-height ratio decreased. For rice seeded in the last ten days of April, optimum seedling characteristics were attained between 15 to 20 DAS at Andong and Euisong and 15 DAS at Kyongsan. At the three locations, 10-day-seedlings exhibited superior characteristics to 15- and 20-day-seedlings for rice seeded in May and June. Rice seedlings of different ages were transplanted at a paddy field to determine the effect of seedling age on yield potential. The mean yield of 10-day-seedlings was 5% higher than that of 35-day-seedlings raised by the conventional method. The yield of 20-day-seedlings was 9% lower than that of 35-day-seedlings. Varietal differences in seedling characteristics of 13 rice cultivars were evaluated for the seedlings seeded in the automatic facility on June. Ten-day old seedlings ranged in height from 13.3 to 17.5 cm and shoot dry weight from 7.7 to 9.4 mg. Two cultivars, Daesanbyeo and Hwayeongbyeo, exhibited superior seedling traits compared to the remaining 11 cultivars and were, therefore, better adapted to the automatic seedling-raising facility.

This study was conducted to investigate most effective the optimum lime content for lime-clay modification. To achieve the aim, characteristics of compaction and compressive strength were tested by adding of 0, 5, 10, 15 and 20% lime (Hydrated lime) of dry weight of the clay. Distilled water was added 10, 15, 20 and 25% of dry weight of lime-clay mixture. In this test, the compressive strength of the specimens was measured according to the following curing period : 7, 21, 28, 35 and 49 days. The results are as follows. (1) As lime additive increased, the optimum moisture content of lime-clay mixture was increased and the maximum dry density was decreased. (2) The soil mixture of 20% of the moisture content and 10% of lime additive was shown the maximum compressive strength. (3) As curing period longer, the compressive strength was increased but after 21 curing days, the increasing rate of compressive strength was low as compared with earlier its value. (4) In the range of 20% of the moisture content, compressive strength of mixture of 10% lime additive increased twice compared with that of mixture of 0% lime additive. (5) All of the lime-clay are possible to use for an sub-base material and 20% of moisture content of lime-clay mixture is possible to use for a base material.