심지재배방법을 이용하여 감자 상위급종서의 대량생산기술을 개발하고자 경삽플러그묘를 SP2, PP2 2종류의 배지와 5종류의 심지수(폭 1.5cm, 길이 40cm)를 처리한 스치로폼 베드(길이 51×폭 31.5×높이 20cm, 0.032m3 )에 정식, 재배하여 배지의 물리성과 생육형질을 조사한 결과는 다음과 같다. 1. 수확직후 총공극량은 SP2배지와 PP2배지간에 차이가 없이 83-85% 수준이었다. 가비중은 배지별로는 Jeju scoria가 혼용된 SP2배지가 0.27g. mL1로 높은 비율을 나타내었으며 심지수간에는 일정한 경향을 보이지 않았다. 2. 수확직후 배지내의 수분함유량은 SP2배지보다 PP2배지가 높았으며 심지수간에는 심지수가 많아질수록 55%에서 70%까지 함량이 많아지는 추세를 보였다. 3. 감자 지상부의 생육형질은 심지수가 많아질수록 증가하는 것으로 나타났다. 4. 1m2 당 총서중과 괴경평균수량은 SP2배지와 PP2배지 모두 심지수 6개에서 가장 높았다.

Eight vermiculite-based root media prepared with addition of complete fertilizer (2 g/L; N-P2 O5 -K2 O, 10-10-14) for potatoes (Solanum tuberosum L.) and a commercial root medium were evaluated in 2000 to develop the root media suitable for potato plug seedling production. The eight media consisted of various ratios of vermiculite, perlite, peatmoss, and compost. In addition, four rates (0, 1, 2, or 4 g/L) of the complex fertilizer for potato were added to a root medium (70% vermiculite, 10% perlite, 10% peat moss, and 10% compost by volume) to determine the optimum addition rate of the complex fertilizer for plug seedlings. Compost addition to the media increased plant height, the number of leaves per plant, and top and root fresh weight of 15-day old plug seedlings. The seedlings raised in root media containing compost produced significantly higher total tuber yield. Addition of the complex fertilizer to root media enhanced seedling growth and increased the number of tubers per plant and tuber yields. The results suggest that root media containing 50% vermiculite, 0 to 20% peat moss, 10% perlite, 20 to 40% compost, and 2 g/L complex fertilizer for potato appear suitable for potato plug seedling production.

Potato (Solanum tuberosum L.) tubers of 10, 20, 30, 40, and 50 g were planted in plug trays with vermiculite-based root medium on 10 August 2000 and grown for 15 days in a glasshouse to determine the effects of mini-tuber size on plug seedling growth and field performance of plug seedlings. For a control, common potato tubers weighing 50 g were also planted. As size of seed tubers planted increased from 10 to 50 g, seedling height decreased from 24.6 to 20.0cm while shoot number per seedling increased from 2.0 to 3.5, main stem diameter from 4.3 to 6.1mm, and fresh weight of root + top from 9.3 to 19.4 g/seedling. At 90 days after transplanting plug seedlings, the total number of tubers per plant increased from 3.62 to 4.72, average tuber weight from 62.9 to 72.8g, and total tuber yield 20.5 to 23.6 t/ha with increase in seed tuber size. Plug seedlings raised from 50g tubers produced 22% more tubers per plant and had 21 % higher＞80g tuber yield than the directly planted potatoes.

For the mass production of plug seedlings in cultivar ‘Dejima’ potato (Solanum tuberosum L.) the optimal apical cutting diameter for rooting and rapid multiplication of stem cuttings in hydroponics were determined. In addition, the best planting date was predicted to increase tuber yield of plug seedlings at fall cropping in Cheju-Do, Korea. Days to initial rooting decreased as the cutting diameter was reduced. Plant height, leaf number, root length and root weight per plant were favorable as the cutting diameter was small. The ideal cutting diameter was 1-2 mm in this experiment. In the hydroponic cultures, the Japanese standard (JS) nutrient solution was the most effective for multiplication of stem cuttings. It was able to propagate more than 20 times a month from a single mother plant. Viability of plants, which were derived from plug seedlings using stem cuttings, was excellent when transplanted to the field. The number of tubers and tuber yield in both of the plug seedlings and seed potato planting plots were high when planted on 25 August. The number and yield were reduced when planted on 15 August, 5 September and 15 September. The degree of decrease of tuber yield in the plug seedling planting plot however, was lower than that of seed potatoes when the planting date was late. In the case of small tubers (under 30 g), the number of tubers and tuber yield were evidently increased in the seed potato tuber planting plot; the yield of large tuber (over 80g) in the plug seedling planting plot was higher than that of the seed potato. The total tuber yield per plant in the plug seedling planting plot was less than that of the seed potato; therefore, in order to increase tuber yield it was necessary to increase field plant density.

The objectives of this study were to find the sprouting condition and to establish the optimum production methods of plug seedlings in yacon (Polymnia sonchifolia Poepp. & Endl.). The sprouting ratio was greatest at 30~pm 1~circC at 20 days after planting. Crowns with single buds were more effective than those with two or more buds for sprouting, which might be due to the apical dominance. Planting the shoots separated from crown after sprouting in the single- and double-layer polyethylene-covered greenhouses reduced seedling period with 25% and 50%, respectively. Planting the shoots after sprouting was more effective than planting the crown buds. Double-layer polyethylene-covered green-house was good for plug seedling production than open field or single-layer polyethylene-covered greenhouse. The bed soils composed of clay loam : compost or sand : compost (1:l=v:v) were more effective to produce plug seedlings than only clay loam, sand or compost. Seedlings could be produced at 30 days after planting in our studies

감자의 생장점 배양을 통하여 생산된 소량의 소괴경(microtuber)을 경삽하여 균일하게 생장된 플러그우량묘를 대량생산할 수 있는 기술을 개발하기 위하여 삽수를 정단 및 기부부위로 구분하고 NAA 및 IAA 10 mg /1 용액에 2시간 침지하여 cocopeat, vermiculite, perlite, peatmoss 혼용배지를 이용한 삽목과 온로장 처리 ,포장정식후 괴경형성효을에 대하여 시험한 결과를 요약하면 다음과 같다. 1. 감자의 소괴경 유내 줄기를 이용한 플러그 삽목시 고체배지는 cocopeat, vermiculite, perlite, peatmoss를 이용한 혼합배지에서 플러그의 형성율이 양호하게 나타났다. 2. 고온장일조건(20℃ 이상, 16시간의 일장)에서는 지상부생육 및 지하부발근이 양호하였으나, 외부방치구에서는 발근이 부진하고 복지가 발생하여 소괴경이 형성되었다. 3. 지상, 지하부 생체중은 생장조절제 전처리시 NAA 10mg/1 및 IAA 10mg/1 간에 차이가 없었다. 4. 삽수부위별로는 삽목묘의 초기생육은 초장에서는 비슷한 경향이었고, 그 외 엽수, 근수, 근장 등의 형질은 정단부위묘가 양호하였지만, 포장정식 후에는 큰 차이가 없었다. 5. 삽목묘를 봄재배하여 괴경형성여부를 시험한 결과 초장은 70~80cm, 복지수 10여개, 괴경수는 7~8개가 형성되었다.

시호의 조직 배양묘와 배양식물의 종자를 이용하여 플러그묘를 생산하기 위한 실험을 수행한 결과를 요약하면 다음과 같다. 1. 재분화식물의 순화를 위해 영양배지없이 증류수, GA(0.1mg/l), putrescine(0.1mg/l)을 소식물체에 흡수시킨 결과 GA처리가 신초 및 뿌리생육에 가장 효과적이었다. 2. 무기염류의 농도를 1/2로 줄인 MS배지와 NAA 0.1ng/l +BA 0.5mg/l 를 조합한 호르몬처리에서 배양묘의 생장과 건물중이 가장 양호하였다. 0.4%의 활성탄물의 관수와 30℃의 온도에서 생장이 촉진되었다. 3, 배양식물의 종자를 파종하여 육성한 플러그묘는 peatmoss상토와 마사토을 혼합한 상토와 원더그로 1, 2, 3호의 배합비를 1. 3-0. 9-0. 3로 하였을 때 생육이 가장 양호하였다. 4. 4%의 보광처리 및 30℃의 온도에서 묘령별로는 90일묘가 가장 생육이 양호하였다.

Methane production from grain dust was studied using a 3 L laboratory-scale anaerobic plug flow digester. The digester was operated at; temperature of 35, 45, and 55℃ hydraulic retention time(HRT) of 6 and 12 days; and influent concentration(S_0) of 7.8 and 9.0 % total solids(%TS). With ten different operation conditions, this study showed the significant effects of temperature, hydraulic retention time, and influent concentration on methane production, The highest methane-production rate achieved was 1.903 (L methane) /(L digester)(day) at 55℃, 6 days HRT, and S_0 of 7.8 %TS. A total of 3.767 L of biogas per day with a methane content of 50.57% was obtained from this condition. The ultimate methane yield(B_0 was found to be a function of temperature and influent concentration, and was described as : B_0= 0.02907T-0.1263-0.00297(T-10)(%TS), where TS is the total solids in the liquid effluent, and T is temperature(℃). Our results showed that thermophilic condition is better than mesophilic for grain dust stabilization in an anaerobic plug flow digester.