• Korean Journal of Weed Science
• /
• v.5 no.1
• /
• pp.43-49
• /
• 1985

This study was conducted to investigate the existance of dormancy in newly collected tubers of Eleocharis kuroguwai Ohwi from paddy fields and to determine the effect of various growth regulators on the bud sprouting and tuberization of E. kuroguwai. The maximum percent sprouting of E. kuroguwai collected at every month during winter was less than 60% regardless of varied collection tunes until 50 days after incubation, suggesting the presence of dormancy in E. kuroguwai tubers. This dormancy was markedly broken as the time went by, probably due to the exposure of tubers the extremly low temperature. The treatment of $BA10^{-3}M$ and $BA10^{-3}+GA10^{-6}M$ increased bud sprouting about 10 and 11 times, respectively, than that of the untreated control indicating that BA seems to be one of the most effective agents among the growth regulators used on the bud sprouting of E. kuroguwai. Foliar application of BA increased tuberization of E. kuroguwai by an average of 34.4% as compared with the untreated control. The highest increase, 39.8% was obtained with BA treatment at $10^{-5}M$.

• 보건세계
• /
• v.55 no.5
• /
• pp.6-9
• /
• 2008

가톨릭의대 예방의학 교수이자 대한결핵협회 부회장을 지낸 바 있는 맹광호 교수가 최근 창립된 한국의사수필가협회 초대 회장직을 맡았다는 소식이 들려왔다. 의사와 수필, 잘 어울리지 않는 듯 어울리는 조합이다. 지난 3월, 40년간 몸담았던 교직에서 퇴임한 후, 더욱 바쁜 나날을 보내고 있는 맹광호 전 가톨릭의대 교수를 만났다.

• Journal of Bio-Environment Control
• /
• v.32 no.2
• /
• pp.172-180
• /
• 2023

This study was carried out to determine the sprouting period of early and mid-season varieties, which includes 'Atlantic', 'Chubaek', and 'Superior', during the summer storage period in a semi-underground warehouse without cooling system. And also it was investigated the effect of chlorpropham [Propan-2-yl N-(3-chlorophenyl)carbamate, CIPC] treatment on the sprouting inhibition for the varieties. This study was conducted to figure out a sprout inhibitory effect when CIPC was applied to 1kg of the potato tubers at concentrations of 10 mg and 20 mg which are lower than the treatment concentrations of ca 30 mg prescribed by the positive list system (PLS). The internal temperature of the warehouse used in this experiment was lowered by 5℃ or more than the outside temperature. The difference between the lowest and highest temperature during the experiment throughout the day was 5℃. It showed the effect of reducing to 1/2 of the difference in outdoor temperature. As for the sprouting of potatoes, the extremely early variety 'Chubaek' sprouts appeared at the 6th week of storage of control and it was the fastest sprouting potato among the control groups of the varieties. Sprouting began to appear in the Superior at the 6th week of storage, while the 'Atlantic' sprouted at the 8th week of storage. The appearance of sprouts was suppressed in all treatment groups of 'Atlantic' and 'Superior' varieties in CIPC treatments. Sprouts were observed in all treatment groups of 'Chubaek' after the 7th week, but the elongations of the sprouts in tubers were completely inhibited until the 8th week of storage. 'Atlantic' and 'Superior' seemed to have a sprouting inhibitory effect even with a low CIPC concentration of 10 mg·kg^-1, with the exception of extremely early variety 'Chubaek' that breaks out of the dormancy quickly. Although weight loss occurred continuously during storage, it was minor loss of 0.7-1.6%. There was no consistent trend for changes of the loss in the varieties and CIPC treatments. Most common pathological disorder was the dry rot during the experiment, but only few were affected. The use of the tubers treated at 18℃ and 90% RH for 10 days and the rack of refrigeration system which lead to lack of convection seemed to have suppressed the spread of pathogens.

• Journal of Korean Society of Forest Science
• /
• v.89 no.4
• /
• pp.497-501
• /
• 2000

Twelve-year-old rootstocks of sycamore and sweetgum were coppiced at monthly intervals for one year. Sprout growth was measured three and five years after cutting. After three years, average dry weight of the sprouts cut in May, June and July was lower by 36% for sycamore and by 24% for sweetgum than those cut during the other months of the year. However, these differences were reduced to be 23% and 14%, respectively, after five years.

• Korean Journal of Weed Science
• /
• v.16 no.4
• /
• pp.264-281
• /
• 1996

As a consequence of wide use of herbicides, Eleocharis kuroguwai Ohwi became a dorminant problem weed for rice cultivation in Korea. To understand the establishment of the weed, experiments on physio-ecological characteristics were carried out sprouting and occurrence, the results could be summarized as follows: Sprouting percentage remained 68 to 73% until the time of field emergence, indicating many of the them are still dormant. The proportion of the dormant tubers were greater for the smaller than the bigger tubers. Apical dominance was apparent in sprouting, with 84% of tuber sprouted from only one of the apical buds. Tubers sprouted from 2 or 3 buds were less than 20%, and were mostly from the bigger tubers. When the shoot growth was compared, by controlling the others, ones from apical and the next 3 buds showed similar vigorous growth, but the later ones showed poorer growth. For the longevity of tubers, deep soil storage appeared to be better than storage in temperature controlled room to 2~$3^{\circ}C$. Emergence of E. kuroguwai was better in clay soil than in sand, and the possible depth for emergence in clay soil appeared to be up to 21cm, but was 15cm in sand. When tubers were exposed to salt solutions before emergence tests, E. kuroguwai appeared to be much sensitive to salts than S.planiculmis. Among the tubers formed in previous year, 12.7% remained still viable until the end of next crop season, but with relatively strong dormancy. The first emergence was about 10 days after planting at ordinary cropping seasons, and the days to the maximum shoot number stage were 60~90 from planting. The duration was extended at early transplanting, and shoot number, leaves per shoot, and tubers developed per plant were also greater at early plantings. The 6th order offshoots were developing when E. kuroguwai was planted at early season. When planted at later seasons, generation and the number of offshoots was reduced planted at early season. When planted at later seasons, generation and the number of offshoots was reduced and the number of tubers, runner and rhizome lengths was also reduced.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.61 no.3
• /
• pp.215-221
• /
• 2016

This study examined the effects of delayed harvest of Miscanthus on its biomass yield and growth characteristics. The trial was conducted at a 5-year-old demonstration field, using Miscanthus sacchariflorus cv. Geodae 1 and Miscanthus ${\times}$ giganteus. Harvesting was carried out using a mower, baler, and bale picker driven by a 5-ton tractor. Harvesting dates were the $1^{st}$, $10^{th}$, and $17^{th}$ of April, which respectively corresponded with the first, mid, and last emerging dates of new shoots. The sequential changes in stem number due to delayed harvesting were investigated on April $29^{th}$, May $27^{th}$, July $22^{nd}$, and October $30^{th}$, which corresponded to the juvenile, mid, luxuriant, and senescence stem stages, respectively. Soil penetration resistance, biomass yield, and growth characteristics were investigated on October $30^{th}$. There was no difference in soil penetration resistance at a depth of 10 cm, but it increased at a depth of 20 cm in proportion to the delayed harvesting time. The sequential change in stem number due to delayed harvesting was greater in M. sacchariflorus cv. Geodae 1 than in M. ${\times}$ giganteus. In M. sacchariflorus cv. Geodae 1, which was harvested on the last emerging date of new shoots, the stem number was $169/m^2$ in the mid stage but decreased to $70/m^2$ in the luxuriant stage. The diameter of newly developed rhizomes, stem height, and biomass yield decreased in the two Miscanthus species due to delayed harvesting. The ratio of Miscanthus headings, which is a critical characteristic for landscape use, also decreased due to delayed harvesting. Heading of M. sacchariflorus cv. Geodae 1 was not observed in plots harvested on the mid and last emerging dates of new shoots.

• Horticultural Science & Technology
• /
• v.29 no.2
• /
• pp.87-94
• /
• 2011

This study was carried out to investigate the effects of hot solution soaking and chilling treatment on sprouting and enlargement of bulblets obtained through in vitro culture in Korean native lilies with ornamental values. In vitro bulblets of Lilium cernuum, L. hansonii, L. hansonii for. mutatum, L. leichtlinii, and L. tsingtauense were soaked in distilled water or 100 $mg{\cdot}L^{-1}$ $GA_3$ and $GA_{4+7}$ solution maintained at $35^{\circ}C$ for two hours (hot water treatment) and/or exposed at $4^{\circ}C$ for 0, 4, or 8 weeks (chilling treatment) and then planted in plastic trays filled with media and grown in a greenhouse at $20^{\circ}C$ and under 16 h photoperiod. In all species, no bulblet propagated by tissue culture sprouted without chilling or hot water treatment due to dormancy. For dormancy breaking, $GA_{4+7}$ hot solution treatment increasing sprouting by 55-96%, whereas distilled water or GA was not effective in sprouting. Chilling treatment for 4 weeks induced sprouting by 50-70% in L. cernuum and L. leichtlinii, whereas 8 weeks was needed for sprouting of L. hansonii and L. hansonii for. mutatum. Combined treatment of hot water and chilling treatments synergistically promoted sprouting. Especially, in L. cernuum and L. hansonii, $GA_{4+7}$ hot solution soaking prior to chilling for 4 weeks promoted sprouting by 35-45% compared with the reverse order. Enlargement of bulblets resulted from increase in fresh weight and diameter was promoted by the treatments that increased the sprouting percentage of bulblets. Only in L. cernuum, shoots emerged from bulblets soaked in hot $GA_{4+7}$ solution or chilled at $4^{\circ}C$ and shoot emergence rate was highest in bulblets soaked in hot $GA_{4+7}$ solution and then chilled for 8 weeks. From these results, the most effective method for bulblet sprouting and enlargement was to soak in hot $GA_{4+7}$ solution and then chill for 4 weeks in L. hansonii, hansonii for. mutatum, and leichtlinii, and to soak in hot $GA_{4+7}$ solution and then chill for 4 weeks in L. cernuum and tsingtauense.

• Korean Journal of Plant Tissue Culture
• /
• v.26 no.2
• /
• pp.137-142
• /
• 1999

This study was carried out to investigate the effects of bulb size, type of media, depth of planting, and nutrient compositions on sprouting and growth of tissue cultured garlic microbulbs in hydroponic culture. Early and increased sprouting were observed when the microbulbs were transplanted into soil planted in shallow (1 cm in depth), while bulb size and fresh weight of the whole plant increased in deep planting (3 cm in depth). Bulb size have greatly influenced on not only sprouting rate but also plant growth after planting. Large bulbs resulted in high growth rate such as number of leaves, stem width, plant height, and increase in bulb size after planting. It was shown that Oriental nutrient solution (N=0.17, P=0.45, K=1.29, Ca=2.44, and Mg=0.98 me/L) was more effective in sprouting and further growth of microbulbs as compared to Yamazaki solution (N=0.27, P=0.16, K=1.50, Ca=1.36 and Mg=0.78 me/L). Microbulbs grown in mixture of leaf mould + bark + sand or Baroko showed the most vigrous growth.

• Horticultural Science & Technology
• /
• v.19 no.4
• /
• pp.515-520
• /
• 2001

To observe the stimulating effect of low dose ${\gamma}$ radiation on the dormancy breaking and growth, microtubers of two potato cultivars (Solanum tuberosum L. cv. Dejima and cv. Superior) were irradiated at the dose of 0.5-30 Gy. Though it varied with cultivars and storage duration, sprouting rate, plant growth and tuber yield were promoted by 2-8 Gy irradiation in microtuber of 'Dejima' stored at low temperature. On the other hand, in microtuber of 'Superior', sprouting rate was promoted by 2 and 4 Gy irradiation, and the growth and tuber yield by 4 Gy irradiation. These results suggest that low dose of ${\gamma}$ radiation could have stimulating effects on the dormancy breaking of microtuber and potato growth.

• Korean Journal of Environment and Ecology
• /
• v.20 no.2
• /
• pp.227-234
• /
• 2006

The comparison of Corylopsis coreana populations between natural groups and deforestation groups is carried in five regions such as Seungju, Woldeung, Hwangjeon in Suncheon, Myeongseok in Jinju and Mt. Baegun in Pocheon. The number of sprouting per both $100m^2$ and each individual stump were appeared more in deforestation than in natural groups. In contrast, the height and the diameter of individuals by the number of sprouting are higher and larger in the natural groups. The relationship between the floristic composition and vegetation in the two groups of C. coreana populations was not appeared. Corylopsis coreana are propagated sprouting as well as seedling in deforestation groups located an opening area. Because of the powerful environmental adaptability through growth of the sprouting and the seedling in deforestation groups, the population of C. coreana are not extinction of species oneself, and on the contrary are showed expansion of C. coreana population after temporary disturbance.