• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.34 no.2
• /
• pp.192-197
• /
• 1989

Two sweet corn hybrids, 'Tanok l' and 'Golden Cross Bantam 70 (GCB 70)' were grown at five plant densities, of 4, 167. 5,556, 6,667. 8, 333, and 11, 111 plants per 10 ares, with or without tiller removal, to determine effects of tiller removal on growth and yield of sweet corn hybrids at various plant densities. Tillers were pulled when less than 15 cm tall. The number of tillers per plant linearly decreased as plant density increased. The two hybrids had similar plant height, ear length and diameter, ear weight and the number of ears per plant and 10 ares. Tanok 1 lodged approximately 20％ at above 8,333 plants per 10 ares, while GCB 70 did not lodge at all, at any plant density. Tanok 1 had higher leaf area index (LAI), ear and stover yields than GCB 70. Except for root lodging and LAI, hybrid x plant density interaction was not significant at 5％ probability level. Plant density did not affect silking data. Increasing plant density linearly increased plant height, LAI, and stover yield, but linearly decreased ear length, ear weight, and the number of ears per plant. Increase in LAI was greater in Tanok 1 than in GCB 70, with increasing plant density. The relationships between the number of ears and ear yield per 10 ares and plant density were Quadratic. The optimum plant density was estimated to be approximately 6500 plants per 10 ares, using the equation based on ear yield. Except for ear height and LA I, hybrid x tiller removal and plant density x tiller removal interactions were not significant. Hybrid x plant density x tiller removal interaction was not significant for any characters. When averaged over hybrids and plant densities, tiller removal reduced plant height and ear and stover yields by about 3, 10, and 16％, respectively, but did not significantly affect silking date, root lodging, ear length and diameter and the number of ears per plant and per 10 ares. The results indicate that the optimum plant density is approximately 6500 plants per 10 ares, regardless of tiller removal and tillers are not to be removed at any plant density.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.29 no.3
• /
• pp.187-196
• /
• 2009

The objectives of this study were to evaluate the different cutting dates on the changes of feed quality among five cereals (barley, wheat, rye, triticale and oat) for whole crop silage. Field trials were conducted at paddy field in Yesan, Chungnam Province and the aerial parts were clipped 10 days from 15 March to 15 June. Changes of acid detergent fiber (ADF) content in relation to different cutting dates was described by a quadratic curve for 5 winter cereals crops. ADF content reached a maximum at 5 days after heading in barley cultivar 'Youngyang', 7 days in wheat 'Keumkang', 18 days in rye 'Gogu', 1 days in triticale 'Shinyoung' and 10 days in oat 'Samhan'. Neutral detergent fiber (NDF) content were linearly increased as growing after overwintering and stagnated or slightly decreased after heading. The crude protein were linearly decreased throughout the growth period of 5 whole crop cereals. Digestible dry matter (DDM) content were decreased from early stages to heading and subsequently increased as grain filling. Relative feed value (RFV) for 5 crops were decreased as growing and subsequently increased as grain filling after heading. Barley cultivar for only forage use 'Youngyang' were lower at ADF and NDF content and higher at DDM and RFV after heading than those of other cereals for forage use. So, barley for whole crop silage was a good crop with high feed quality and high proportion of spikes compared with other winter cereal crops. Wheat cultivar for grain 'Keumkang' were higher at crude protein than those of other four cereals from overwintering to maturing and were higher at DDM and RFV after heading than those of rye, triticale and oat. Rye cultivar with cold tolerant and high fresh yielding 'Gogu' were highest at ADF and NDF content and lowest at DDM content and RFV. So, rye was a crop with low quality for forage use compared to other winter cereal crops. Triticale cultivar with flourishing and high yielding 'Shinyoung' was intermediated between barley and rye, and were linearly increased at DDM yield by different cutting dates. Oat cultivar with cold tolerant and high tillering 'Samhan' were lower at ADF and NDF content and higher at crude protein before heading, but after heading, there are not especially advantages compared to barley, wheat or triticale.

• Journal of Animal Science and Technology
• /
• v.45 no.2
• /
• pp.183-190
• /
• 2003

Data from live animal real time ultrasound (RTU) measures from 127 Hanwoo steers were used to assess nutritional physiology and relationship between RTU measures and real carcass measures represented meat quality. Traits considered were longissimus muscle area, fat thickness, and marbling score imaged and scanned using RTU by month and those of carcass measures at about 24 month of age. On this study, increasing pattern for longissimus muscle area would be closely related to growth pattern (p<0.01) and it of fat thickness would be related to quadratic effect of ages. Marbling score would be related to aging, that is, individual deviates of scores were distinctly characterized after 17 mo. even though they were started at about 11 mo. Correlation estimates between RTU measures and corresponding carcass traits were over 0.6 after 17 month of age for all traits considered and these estimates were high as 0.90 after 22 month of age. From this study, Real-time ultrasound measurement would be valuable after 15-17 mo. and measures at about 22 mo. would be helpful to decide age for slaughtering. To utilize these techniques for beef cattle breeding via progeny testing program, 15 mo. RTU measures would be efficiency rather than 12 mo. of other beef breeds. Further study to find genetic variation of RTU measures was needed to utilize these technologies for beef breeding.

• Radiation Oncology Journal
• /
• v.12 no.1
• /
• pp.27-31
• /
• 1994

There are a number of reports suggesting that there may be a correlation between the clinical response to radiotherapy in various tumors and the clonogenic survival of cell lines derived from these tumors following exposure to 2 Gy(SF2). Authors conducted this study to determine SF2 for cells in primary culture from surgical specimens. The tumor tissues with squamous cell carcinoma of uterine cervix and head and neck were obtained. The tumor tissues were disaggregated to single cells by incubating with collagenase type w for 2 hours with constant stirring. Single cell suspensions were inoculated in four 24-well plates precoated with cell adhesive matrix. After 24 hours of incubation at 37$ ^{\circ}C $, rows of four wells were then irradiated, consisting of control set and five other sets each receiving doses of 1,2,3,4, and 6 Gy. After incubation for a total of 13 days, the cultures were stained with crystal violet and survival at each dose was determined by quantitative image analysis system, To determine whether cell growth was of epithelial origin, immunocytochemical staining with a mixture of cytokeratin and epithelial monoclonal antibodies were performed on cell cultures. During the period of this study, we received 5 squamous cell carcinoma specimens of head and neck and 20 of uterine cervical carcinoma. Of these, 15 yielded enough cells for radiosensitivity testing. This resulted an overall success rate of 60$ \% $. The mean SF2 value for 15 tumours was 0.55$\pm$0.17 ranging from 0.20 to 0.79. These results indicate that there is a broad range of sensitivities to radiation in same histologic type. So with a large patient population, we plan to determine whether a different SF2 value is associated with tumours that are controlled with radiotherapy than those that are not.