• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.69 no.3
• /
• pp.133-144
• /
• 2024

To review active climate change responses, especially adjustments to the transplanting time, seven varieties of early-maturing ecotypes grown at Sangju sub-station, located in a mid-mountainous region, were studied from 2007 to 2022. During the ripening stage (July 29 to October 17), the average temperature was 23.2℃, which was a relatively disadvantageous environment compared to the optimal ripening temperature of 20 to 22℃. The heading date of early-growing cultivars was greatly shortened by 10 days for both normal (May 20) and late (June 5) transplanting. In an analysis of the growth characteristics and yield components, the culm and panicle length, number of spikelets/panicles, and the ripening rate showed high variation without a constant tendency over the study period. However, the number of panicles/plants and the ratio of brown rice increased, regardless of the transplanting time, while the 1,000-grain weight tended to decrease. There were no significant differences in yield observed between the two transplanting times, except for some years. Therefore, based on various variables, such as growth, yield, and quality (although not assessed in this study), the shift in transplanting time for early-maturing varieties in the mid-mountainous region from the current time (May 20) to a later time (June 2) needs to be considered to cope with the future impacts of climate change.

• Korean Journal of Breeding Science
• /
• v.40 no.4
• /
• pp.484-489
• /
• 2008

A new whole crop silage barley cultivar, "Youngyang", was developed from the cross between "Bunong and Milyang55 at the Yeongnam Agricultural Research Institute (YARI) in 2002. An elite line, YB3882-3B-17-1-3-1, was selected in 1999 and designated as "Milyang111". It showed good agronomic performance in the regional adaptation yield trials (RYT) from 2000 to 2002 and was released by the name of "Youngyang" with higher yield and better animal feed quality than that of Olbori. The average heading and maturing dates of Youngyang were May 2 and June 6, which were late by 2 & 1 days than those of Olbori, respectively, in Suwon. Youngyang had longer culm length, 83cm but it had lesser spikes per $m^2$ 637 than that of Olbori, respectively, in RYT from 2000 to 2002. The rate of leaf sheath/whole length (culm+leaf) and the rate of the grains/whole crop weight was similar to Olbori. It showed resistance to BaYMV at the regions of Naju, Jinju, Milyang andt Iksan. however, the response of Youngyang to other environmental stresses (tolerance of cold and wet) was similar to Olbori. The dried whole crop yield potential of Youngyang in the RYT was about 11.67 MT/ha in paddy fields which was about 18% higher than that of Olbori. The grain yield potential was 6.32 MT/ha in paddy fields which was about 5% higher than that of Olbori. Youngyang had lower rate of shattering, higher content of protein and NDF, lower ADF and TDN, and better quality of silage than those of Olbori.

• Korean Journal of Soil Science and Fertilizer
• /
• v.45 no.5
• /
• pp.772-778
• /
• 2012

In order to develop the application method of compost manure (CM) and liquid manure (LM) for rice cultivation, experiments were conducted at silty loam paddy field in Gochang, Jeonbuk, a LM applied rate as N%; non-application, chemical fertilizer (CF) 100%, CM 50%+LM 50%, CM 30%+CF 70% and CM 30%+LM 70% as basal and additional fertilizer. $NH_4^+$-N content in paddy soil was higher with CF 100% application than the split application of compost and liquid pig manure fertilizer during the early stage of rice growth. However, there was no significant difference in the later part of rice growth. Amount of $NO_3^-$-N in leachate was decreased in CM 30%+LM 70% and CM 30%+CF 70% split applications compared to CF 100%. Amounts of OM and Avail $P_2O_5$, Exch. cations in soil of experiment after were highest with the split application of CM 50%+LM 50% and CM 30%+LM 70%. Amount of nutrient uptake of plants were no significant difference between the split application plots of CM and LM, but nitrogen utilization rate was 66% in average CM 50%+LM 50% and CM 30%+LM 70% to compared CF 100%. The rice yield of CM 50%+LM 50% was lower (90%) comparing that of CF 100% ($557kg\;10a^{-1}$). But the yield in CM 30%+CF 70% and CM 30%+LM 70% reached 96% in average, which did not show significant difference with that of CF 100%. Accordingly, LM 70% or CF 70% split application after CM 30% application was helpful in enhancing the physicochemical property of soil as well as reducing CF. It could be evaluated that this application in segmentation was better in productivity improvement and soil pollution reduction than the esinultaneous application of LM 100% in terms of split application in times of requirement for plants.

• Journal of Bio-Environment Control
• /
• v.17 no.4
• /
• pp.336-341
• /
• 2008

The objective of this research was to investigate the suitable cultivar for organic strawberry (Fragaria ananassa Duch.) cultivation in Korea. The six strawberry cultivars which were bred and commonly cultivated in Korea as forcing and semi-forcing culture were tested in this experiment. To achieve the objectives, various characteristics of these cultivars were investigated for two consecutive years such as growth habit, yield, fruit quality and occurrence rate of disease/pest. As results of this research, the total yield of 'Seolhyang' was the highest among cultivars tested in both forcing and semi-forcing cultivation. The average of soluble solid contents (SSC) in 'Seolhyang' was $12.0^{\circ}Bx$ that is lower than other cultivars and especially below $10^{\circ}Bx$ after March (high temperature period). But there was not much difference in SSC among 6 cultivars until the end of February. The average of hardness in 'Seolhyang' was 279g/${\phi}5\;mm$ which was a little higher than that of 'Akihime'. Titration acidity (TA) in 'Maehyang' was 0.69% which was the highest value among 6 cultivars. Total fresh/root weight of 'Seonhong' and leaf area of 'Seolhyang' were significant among other cultivars' ones in forcing culture. Growth habits (fresh weight, root weight, leaf area, etc.) showed no significant difference among cultivars in semi-forcing culture. The lowest occurrence rate for powdery mildew and aphids was found in 'Seolhyang', but gray mold was severer than other cultivars. The density of two spider mites was the lowest in 'Redpearl'. We have concluded that 'Seolhyang' is the most suitable cultivar for organic strawberry cultivation by the result of yield, fruit quality and resistance of disease/pest.

• Applied Chemistry for Engineering
• /
• v.10 no.7
• /
• pp.1052-1060
• /
• 1999

Tire and raw material of tire, i.e., SBR were degraded using pyrolysis process. The yield of pyrolytic oil was increased and that of gas was decreased with increase of operating temperature in pyrolysis. And the yield of pyrolytic oil was increased and that of gas and char was decreased with increase of heating rate. The maximum oil yields of SBR and tire were 86% and 55% each at $700^{\circ}C$ with a heating rate of $20^{\circ}C/min$. The number average molecular weight ranges of SBR and tire were 740~2486, 740~1719, and the calorific value of SBR and tire was 39~40 kJ/g. The oil components were consisted of mostly 50 aromatic compounds. The particle size was decreased and the surface area was increased with increase of operating temperature, and the BET surface area was $47{\sim}63m^2/g$. The optimum condition of pyrolysis was the temperature of $700^{\circ}C$ with heating rate of $20^{\circ}C$, and the reactor was continuously purged with inert gas to sweep the evolved gases from the reaction zone.

• Journal of Bio-Environment Control
• /
• v.4 no.2
• /
• pp.175-180
• /
• 1995

This study was conducted to establish the nondestructive nutrient diagnosis method for nitrogen in tomato leaf using SCDS(specific color difference sensor). NFT(nutrient film technique) system was used in this experiment and nitrogen concentrations treated in nutrient solution were 0, 10, 50, 100, 150, 200, 300 and 600ppm. As nitrogen concentration in nutrient solution was increased from 0ppm to 150ppm, the stomatal resistance of tomato leaf was decreased abruptly, the $CO_2$ assimilation rate was increased but there was no big difference in the range of 100-500ppm. As the SCDS value of tomato leaf was increased, the $CO_2$ assimilation rate was increased linearly but the total average fruit weight and marketable yield were increased quadratically. The $CO_2$ assimilation rate was largely increased in the 0-3% range of leaf nitrogen content, but photosynthetic saturation was shown in 3.3-3.5%. The leaf nitrogen content was closely related to SCDS value of tomato leaf. Considering physiological activity, growth and yield of tomato, the optimum ranges of leaf nitrogen content were found to be 3.0-3.8% and the SCDS values equivalent for those ranges were 40.0-52.2.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.2 no.2
• /
• pp.65-75
• /
• 1994

The aim of this experiment was to investigate the effects of applying time of cattle slurry and fertilizing added mineral nitrogen on dry matter yield of orchardgrass and also to estimate proper levels of fertilizing nitrogen when idled arable land rapidly increased these days, which was used for the production of Orchardgrass. The results were as follows. 1. The annual yields of dry matter were produced 5.62~6.67 ton per ha when cattle slurry applied at rates of $30m^3$(average mineral fertilizer equivalent to 120kg) per ha in different dressing times. Those were higher 0.60~1.65 ton or 0.16 ton per ha than the yields from non-fertilizing or phosphrous and potassium fertilizing. 2. Relative yields of annual dry matter from mineral nitrogen fertilization of 120kg per ha were 142~146% in comparsion with control plots(cattle slurry plot or phosphrous and potassium plot). On the other hand, those of cattle slurry application were 112~133% in comparion with non-fertilizing plot. 3. The efficiencies of nitrogen on dry matter yield(kg DM/kg N) were 5.0~13.8 DM kg/N kg when cattle slurry applied to Orchardgrass at rates of $30m^3$(average mineral fertilizer equivalent to 120kg) per ha, and were 21.3~23.1kg DM/kg N at the same level fertilization of mineral nitrogen. 4. On the condition of this study, mineral nitrogen were fertilized after applying cattle slurry at rates of $30m^3$(average mineral fertilizer equivalent to 120kg) per ha in order to minimize chemical fertilizer and increase the potential production of Orchardgrass. At this situation, marginal dry matter yields of 8.48~8.63 ton per ha were obtained as the level of economic even point goint when mineral nitrogen fertilization is between 119.4 and 133.3kg per ha. It was possible to obtain the maximal dry matter yield(8.98 tons/ha) with fertilization of 202.8kg N/ha.

• Korean Journal of Medicinal Crop Science
• /
• v.12 no.3
• /
• pp.219-225
• /
• 2004

This study was conducted to evaluate growth and yield characteristics and the contribution to the yield according to the emergent sequence of tiller under two planting density $(60{\times}15\;cm,\;60{\times}25\;cm)$ in Coix lachryma-jobi L. var. mayuen Stapf. The average culm length and number of rachillas of $60{\times}25\;cm$ planting density were 20 cm shorter and 4.7 higher, respectively, whereas seed setting position of $60{\times}25\;cm$ planting density was 1.7 nodes lower compared with $60{\times}15\;cm$ planting density. Culm length and culm diameter of each tiller became shorter and thinner as the tiller emerged later. Length of rachillas was longer, number of grains was higher and ripening rate was also higher in $60{\times}25\;cm$ planting density than those of $60{\times}15\;cm$ planting density, whereas 100 grain weight in $60{\times}25\;cm$ planting density was lower by 0.5 g compared with $60{\times}15\;cm$ planting density. Length of rachillas and number of grains according to the emergent sequence of tiller were shown shorter and lower as the tiller emerged later. The highest number of bract was obtained from the main culm in both planting densities. 100 grain weight according to the emergent sequence of tiller became lower as the tiller emerged later in $60{\times}15\;cm$ planting density, but there was no clear tendency in $60{\times}25\;cm$ planting density. Among 8 tillers, 5th tiller and 4th tiller of main culm contributed 84.4% to the yield in $60{\times}15\;cm$ planting density, while it was 84.1% in $60{\times}25\;cm$ planting density. Analysis of path coefficient to grain yield showed that direct effect was the highest in the number of grain per tiller followed by in the 100 grain weight and in ripening rate.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.40 no.2
• /
• pp.106-110
• /
• 2020

The purpose of this study was to evaluate winter annual forage crops for yield, and horse palatability under horse grazing during the fall and spring in Jeju. The winter annual forage crops such as Italian ryegrass(IRG), rye, and oat were planted in randomized block design in October 30. The horse grazing was initiated on March 17 of the following year. At the first cutting, the dry matter yield of rye was the highest with 4,600 kg/ha compared to the IRG and oat (p<0.05). But there were no significantly different in the yield of winter annual forage crops after the second and third harvests. The total dry matter yield showed rye 12,593 kg/ha, IRG 10,941 kg/ha, and oat 9,424 kg/ha respectively. The horse intake duration of the IRG was significantly higher than the oat and rye (p<0.05). In the first grazing and the second grazing, the intake duration of the IRG was 853.2 seconds and 989.4 seconds, respectively, with oat at 147.6 seconds, and 73.0 seconds, and rye at 89.4 seconds, and 33.18 seconds. The intake duration of IRG was longer than that of oat and rye (p<0.05). The intake rate of the IRG was 60.0% in the first and 82.8% in the second, and the average intake rate was 71.4%. When considering the maintenance of pastures and the palatability of horses, the IRG is the most suitable forage crop in winter annual forage crops in Jeju.

• Korean Journal of Breeding Science
• /
• v.41 no.2
• /
• pp.130-136
• /
• 2009

"Hanbaek", a white winter wheat (Triticum aestivum L.) cultivar was developed by the National Institute of Crop Science, RDA. It was derived from the cross "Shan7859/Keumkang"//"Guamuehill" during 1996. "Hanbaek" was evaluated as "Iksan314" in Advanced Yield Trial Test in 2005. It was tested in the regional yield trial between 2006 and 2008. "Hanbaek" is an awned, semi-dwarf and hard winter wheat, similar to "Keumkang" (check cultivar). The heading and maturing date of "Hanbaek" were similar to that of "Keumkang". Culm and spike length of "Hanbaek" were 89 cm and 9.0 cm, which longer culm length and spike length than "Keumkang" (80 cm and 7.9 cm, respectively). "Hanbaek" had lower test weight (797 g) and higher 1,000-grain weight (47.7 g) than "Keumkang" (813 g and 44.9 g, respectively). "Hanbaek" showed resistance to winter hardiness and susceptible to pre-harvest sprouting, which lower withering rate on the high ridge (4.4%) and higher rate of pre-harvest sprouting (47.9%) than "Keumkang" (21.9% and 30.4%, respectively). "Hanbaek" had similar flour yield (74.4%) to "Keumkang" (74.1%) and higher ash content (0.45%) than "Keumkang" (0.42%). "Hanbaek" showed lower lightness (89.13) and similar redness and yellowness (-0.87 and 10.93) in flour color than "Keumkang" (90.02, -1.23 and 9.28, respectively). It showed similar protein content (12.8%) SDS-sedimentation volume (63.0 ml) and gluten content (10.8%) to those of "Keumkang" (11.9%, 62.3 ml and 10.2%, respectively). It showed lower water absorption (59.6%) and mixing time (3.8 min) in mixograph and higher fermentation volume (1,350 ml) than those of "Keumkang" (60.6%, 4.7 min and 1,290 ml, respectively). Amylose content and pasting properties of "Hanbaek " were similar to those of "Keumkang". "Hanbaek" showed same compositions in high molecular weight glutenin subunits (HMW-GS, 2*, 13+16, 2+12), granule bound starch synthase (Wx-A1a, Wx-B1a, and Wx-D1a) and puroindolines (Pina-D1a/Pinb-D1b) compared to "Keumkang". "Hanbaek" showed lower hardness (4.22N) and similar springiness and cohesiveness of cooked noodles (0.94 and 0.63) to those of "Keumkang" (4.65N, 0.93 and 0.64, respectively). Average yield of "Hanbaek" in the regional adaptation yield trial was 5.98 MT/ha in upland and 5.05 MT/ha in paddy field, which was 8% and 6% higher than those of "Keumkang" (5.55 MT/ha and 4.77 MT/ha, respectively). "Hanbaek" would be suitable for the area above the daily minimum temperature of $-10^{\circ}C$ in January in Korean peninsula.