• Journal of Biosystems Engineering
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• 제28권2호
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• pp.151-156
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• 2003

This study was performed to investigate the effect of light quality on evapotranspiration and graft-taking characteristics of watermelon grafted seedlings using blue, red and far-red light-emitting diodes (LED). At initial stage of graft-taking, blue light increased the evapotranspiration rate (EVTR) of grafted seedlings as compared to effects of red and far-red on EVTR of grafted seedlings. Grafted seedlings graft-taken under red and blue LED showed the high graft-taking of 100% and 96%, respectively. However, grafted seedlings graft-taken under far-red LED showed the graft-taking of 80% and survival of 60% with low seedlings quality after hardening. The stem of grafted seedlings graft-taken under red light was elongated but blue light suppressed the stem elongation. The leaf area of grafted seedlings graft-taken under red light was increased. It is concluded that the effect of light quality using LED on graft-taking of watermelon grafted seedlings was significantly recognized. Considering the duration of quality of grafted seedlings graft-taken under artificial lighting, LED could be used as an effective lighting sources to validate the continuance of seedling quality.

• Journal of Ginseng Research
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• 제42권2호
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• pp.208-217
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• 2018

Background: The quality differences in seedlings of medicinal herbs often affect the quality of medicinal parts. The establishment of the grading standard of Panax notoginseng seedlings is significant for the stable quality of medicinal parts of P. notoginseng. Methods: To establish the grading standard of P. notoginseng seedlings, a total of 36,000 P. notoginseng seedlings were collected from 30 producing areas, of which the fresh weight, root length, root diameter, bud length, bud diameter, and rootlet number were measured. The K-means clustering method was applied to grade seedlings and establish the grading standard. Results: The fresh weight and rootlet number of P. notoginseng seedlings were determined as the final indices of grading. P. notoginseng seedlings from different regions of Yunnan could be preliminarily classified into four grades: the special grade, the premium grade, the standard grade, and culled seedlings. Conclusion: The grading standard was proven to be reasonable according to the agronomic characters, emergence rate, and photosynthetic efficiency of seedlings after transplantation, and the yields and contents of active constituents of the medicinal parts from different grades of seedlings.

• Journal of Ginseng Research
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• 제12권1호
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• pp.68-75
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• 1988

산지 반양직묘포 29개포장을 대상으로 육묘방법 및 묘삼생산량을 조사하고 그들 상호간의 관계를 분석하였던 바 그 결과는 다음과 같다. 1. 사용가능묘삼수는 간($180{\times}90$)당 362본, 전묘삼수에 대한 사용가능묘삼수비율(사용가능묘삼비율)은 45%였으며 농가간에 그들의 변이가 심했다. 2. 반양직묘포에서의 사용가능묘삼량은 중량미달묘삼량과 달랭이 묘삼량에 지배되었다. 3. 달랭이 묘삼비율은 상고 및 관수회수와 부의 상관이 각각 인정되었다. 4. 사용가능묘삼비율은 일복의 전.후주 높이와 곡선상관, 일복폭과 부의 상관, 관수회수와는 정의 상관이 각각 인정되었다.

• The Korean Journal of Ecology
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• 제17권2호
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• pp.131-141
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• 1994

One-year-old yellow-poplar (Liriodendron tulipifera L.) and sweetgum (Liquidambar styraciflua L.) seedlings were exposed to 0.10 ${\mu}l/l\;O_3$and simulated acid rain at pH 3.0 for ten consecutive weeks. Shoot height growth (SHG), fresh weight (FWT), dry weight (DWT), apparent plastochron duration (APD) and foliar nutrient concentrations were measured. None of growth measurements, except the apparent plastochron duration (APD), were significantly affected by any treatment in yellow-poplar seedlings. APD was approximately 30% higher in seedlings exposed to $0.1{\mu}l/l\;O_3$ ＋ pH 5.6 solution than any other treatment. Ozone significantly reduced SHG of sweetgum seedlings by 24% at the end of the ten-week fumigation. There were also significant effects of single and combined effects of ozone and simulated acid rain on APD in sweetgum. APD was significantly increased by 19.8% and 25.7% in seedlings exposed to $0.1{\mu}l/l\;O_3$ and pH 5.6 solution, respectively, and resulted in 46.1% higher APD in seedlings exposed to $0.1{\mu}l/l\;O_3$ + pH 5.6 solution compared with seedlings exposed to $0.0{\mu}l/l\;O_3$ ＋ pH 3.0 solution. Phosphorus and sulphur were significantly greater in seedlings exposed to simulated rain at pH 3.0 compared with pH 5.6 for both species. Foliar S concentration was higher in seedlings exposed to $0.0{\mu}l/l\;O_3$ ＋ pH 3.0 than in seedlings exposed to any other treatment in sweetgum. Ozone significantly increased Ca in sweetgum seedlings, however, ozone reduced Ca in yellow-poplar. Ozone also reduced S and Mg in sweetgum seedlings.

• 한국작물학회지
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• 제37권2호
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• pp.198-208
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• 1992

Recently, a nursery mat made from rock wool has realized transplanting of the younger seedlings with the ordinary transplanting machines for Chibyo and Chubyo(3 and 4～5 leaved seedling, respectively). The seedlings defined as the 'Nyubyo' or 'Nursling seedlings' became possible to achieve economic profits from the reduction in both working time and costs. It being widely noticed as a strategy to solve the difficulties in current rice cultivation. The nursling seedlings are 1.4 to 2.5 leaves and height at 4.5 to 7cm, grown 4 to 7 days after seeding. They maintain still up to 50 to 80% of their nutrients in the endosperm, and can grow by using only their own nutrients for a certain period of time after transplanting. Nursling seedlings take 2 days in the nursery chamber at 32$^{\circ}C$ after seeding, and 2 days in the greening house at $25^{\circ}C$. This is only 4 days, all together, to make the nursling seedlings of 1.5 leaves which are ready for transplanting. Watering is only needed once at the sowing time. It only takes 1 or 2 waterings even to raise a seedlings for a period of 7 days. The number of nursery boxes can be reduced because it is possible to sow more densely(220 to 240g per box), thus it only needs seedlings of 15 to 16 boxes per 10 a which leads to a reduction in facilities and space needed. Temperature during the nursery period can be artificially adjusted more precisely which may lead to the prevention of temperature stress. The nursling seedlings can root rapid by because the crown roots from the coleoptile node begin to emerge immediately after transplanting. They show strong resistance to low temperature (12$^{\circ}C$) and deep-planting. There is no danger in the rooting of the seedlings even if half of their height is buried into the soil. Moreover, it can root at a rate of up to 65 to 80% even if the full height of the seedlings is buried. They show also strong resistance to submergence (10～15cm). The nursling seedlings tend to grow by producing tillers from lower nodes. It is therefore, necessary to control to keep the proper numbers of tillers per unit area. They have no fear in the delay of heading and their yield components can be so well balanced that the same level of yield was achieved with the nursling seedlings compared to that with Chibyo. It was further suggested that if the surplus tillers can be avoided by such cultivation practices, the number of grain per panicle can be kept greater and higher yield can be realized. Practical experiments with the nursling seedlings conducted in 1989 and 1990 by farmers in various areas showed exciting results. The nursling seedlings will become widely spread, or at least occupy an important position in Japanese and also in Korean rice cultivation techniques.tivation techniques.

• 원예과학기술지
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• 제34권5호
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• pp.771-778
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• 2016

Seedless grape (Vitis spp.) cultivars with large berries can be developed from hypo- and hypertetraploid seedlings. The low occurrence of hypo- and hypertetraploid seedlings, however, has impeded the breeding of new hypo- and hypertetraploid grape varieties. In order to establish hypoand hypertetraploid seedlings, we examined the chromosome numbers in seedlings of self-, open-, and cross-pollinated hypotetraploid 'Takao' and hypertetraploid 'RB9127K' grape. Three of the five seedlings (60%) from 'Takao' were aneuploid, including one with 74 chromosomes (2n=4x-2) and two with 75 chromosomes (2n=4x-1). In 'RB9127K', 26 of the 193 seedlings (13.5%) were aneuploid, including three seedlings with 75 chromosomes (2n=4x-1), 18 with 77 chromosomes (2n=4x+1), and five with 78 chromosomes (2n=4x+2). The high frequency of aneuploids from 'Takao' and 'RB9127K' grape indicates that meiosis in hypo- and hypertetraploid female parents is prone to segregation error. These results suggest that various hypo- or hypertetraploid seedlings can be successfully produced using hypo- or hypertetraploid grapes as female parents, which can contribute to the development of new seedless grape varieties with large berries.

• 원예과학기술지
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• 제31권4호
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• pp.483-489
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• 2013

The abnormal seedlings, a common physiological anomalies, emerged during embryo rescue severely restricted grape breeding. To enhance the efficiency of the seedless grape breeding by reducing the production of abnormal seedlings in the course of embryo rescue, we investigated the effects of genotype, media type, embryo style, pre-chilling on the deformity rate of the abnormal seedlings during embryo rescue. The abnormal seedlings were firstly classified into seven categories based on their morphology. Our results indicated that the emergence of abnormal seedlings was highly dependent on the female parent genotype. Polyembryony was advantageous to diminish the number of abnormal plantlets and the germination rate of embryo was 100%. We also found that pre-chilling treatment could reduce the number of abnormal plantlets and promote the embryo germination. The abnormal plantlets were reduced significantly by the addition of $ZnSO_4$ $10{\mu}mol{\cdot}L^{-1}$ or mashed-banana $500mg{\cdot}L^{-1}$ to either embryo development or germination media. Transferring the abnormal seedlings onto the suitable fresh media in 4 weeks after embryo germination provided an effective way to transform them into normal seedlings.

• 한국산림과학회지
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• 제101권2호
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• pp.317-323
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• 2012

본 연구는 우리나라 남부지방의 주요 조림수종인 편백(Chamaecyparis obtusa Sieb. et Zucc.) 노지묘와 용기묘의 생육단계별 생장특성을 탐구하고자 수행되었다. 1년생 노지묘의 간장생장은 용적이 31.2 mL와 300 mL 용기에서 생장한 용기묘 보다 좋았으며, 근원경 생장은 300 mL 용기의 용기묘가 가장 좋았다. 2년생 노지묘는 300 mL 용기의 용기묘보다 간장 및 근원경생장이 양호한 것으로 조사되었다. 건물생산량 비교에서, 1년생 지상부는 32 mL 용기묘가, 지하부 및 전체 건물생산량은 300 mL 용기묘가 가장 높았다. 2년생의 경우는 지상부는 노지묘가, 지하부는 용기묘의 건물생산량이 높은 것으로 나타났다. 뿌리전체길이, 뿌리투영단면적, 뿌리표면적, 뿌리평균직경, 뿌리부피 등 묘목의 뿌리형태 특성 비교에서, 1, 2년생 용기묘 모두 뿌리평균직경을 제외하고는 노지묘보다 더 높은 생장을 보였다. 본 실험의 결과를 종합해 볼 때, 편백 묘목생산과정에서 용기묘가 노지묘에 비해 상대적으로 뿌리발달이 뛰어난 묘목으로 생장한 것으로 판단된다.

• 한국산림과학회지
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• 제28권1호
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• pp.36-42
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• 1975

밤나무 종자(種子)의 발아초기(發芽初期)에 유근(幼根)과 유경(幼莖)을 할절(割切), 단일종자(單一種子)로부터 여러쌍(雙)의 동일유전자형(同一遺傳子型)을 얻는 방법(方法)으로 본연구(本硏究) 결과(結果), 밤나무종자(種子)의 유근(幼根)과 유경(幼莖)을 일주(一週) 간격(間隔)으로 1-3회(回)로 나누어 할절(割切)하여 2-8개체(個體)의 동일유전자형(同一遺傳子型)을 만들었다. 그 생장율(生長率)은 90-100%이며, 일회(一回)의 할절묘(割切苗)는 수회(數回)의 할절묘(割切苗)보다 생존율 생장량 및 T/R율(率)이 불량(不良)하고, 단일종자(單一種子)에서 얻은 4개체(個體)까지는 정상묘(正常苗와) 별 차이가 없고, 외부형태(外部形態)도 완전(完全)한 원형(原形)을 회복하였다.

• International Journal of Industrial Entomology and Biomaterials
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• 제8권2호
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• pp.201-205
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• 2004

During the routine survey, the mortality of mulberry seedlings was noticed due to damping-off disease. The disease recognized by rotting of emerged seedlings near the soil line (just below the soil level) resulting in collapse of the seedlings. Two fungi were isolated from affected samples and identified as Alternaria alternata (Fr.) Keissler and Fusarium solani (Mart.) Sacc. Both the fungi were found to be responsible in causing pre and post emergence damping-off of seedlings in mulberry. For management of the disease, an experiment was conducted using fungicides. These fungicides were applied as seed treatment; soil drenching and foliar spray alone and in combination. Among the different treatments, integration of seed treatment and soil application of Dithane M-45 (Mancozeb 75% WP) + Bavistin (Carbendazim 50% WP) followed by foliar spray of these fungicides (after 35 days of sowing) resulted in better survivability of seedlings (93.3 %) on $90^th$ day and controlled the pre and post emergence damping off by 100 and 89.5%, respectively over the check.