• 한국초지조사료학회지
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• 제14권2호
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• pp.125-131
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• 1994

This experiment was canied out to study -the effects of different seeding date on the yields and nutritional value of Pearl millet. Seeding dates were $S_1$,$S_2$,$S_3$,$S_4$, and $S_5$, and harvest dates were $S_1$, (7 July) and $S_2$, (18Augst), respectively. The results were summarized as follows: 1. Plant length was not influenced by seeding date at each harvest. The seeding date at $S_4$,showed the longest plant length of 90.4 an on average per year, which was longer by 17 cm compared to 73.3 cm harvested at $S_5$. 2. Total dry matter yield was not significantly different among seeding dates. Total dry matter yield in 1993 increased according to delayed seeding date from $S_1$ to $S_4$. Dry matter yield of 17.3 tonha was obtained in $S_4$. 3. The relative yield of leaf tended to increase with delayed seeding date, and varied from 60% to 69%. 4. Dry matter ratio decreased with delayed seeding date from $S_1$,(20 April) to $S_5$ (30 May), and varied from 15.6% to 12.3%. 5. Crude protein content of leaf at 1st and 2nd harvest and stem at 1st harvest were significantly different among various seeding dates. Avenge crude protein content increased with delayed seeding date from 9.0% at $S_1$ (20April) to 12.8% at (30 May) $S_5$ (30 May). 6. NDF and ADF of leaf at the 1st harvested were significantly different among seeding dates. NDF content decreased with delayed seeding date from 61.9% to 57.8%, and ADF content decreased with delayed seeding date from 34.8% to 32.2%.

• 한국초지조사료학회지
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• 제8권1호
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• pp.47-54
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• 1988

The growth characteristics and yield per unit area of two cultivation systems of forage, corn (Zea mays L.) monoculture and corn-cowpea (Vigna sinesis King) inter-cropping were compared and obtained follow results. 1. The two cultivation systems were not significantly different in leaf length, leaf width and length of internode with harvesting time. 2. The weight of stalk and leaves of a plant were decreased with maturity, while weight of ear was markedly increased. The patterns of relative ratio of each components was essentially same in each cultivation system. In corn monocrop., the percentages of stalk, leaf and ear at final harvesting stage were 22.9, 13.7 and 63.4, respectively. 3. Dry matter yield per unit area (33kgIlOa) of intercropped corn at yellow stage was similar to that of monocropped corn ( l,482.8kg/ 10a vs 1 ,SO8.9kg/ 10a). At ripe stage, however, the DM yield of intercrop. was higher than that of monocrop. (1,810.4kg/lOa vs 1,660.4 kg/ 1 Oa). 4. The same pattern was observed in organic matter yield.

• 한국초지조사료학회지
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• 제11권1호
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• pp.22-29
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• 1991

This study was experimented to obtain the basic information on the changeable aspect and improvement of soil fertility in newly-reclaimed sloped land. Silage corn was cultivated under the six different treatments for 4 years. The relation between the amount or ratio of annual changes of soil physico-chemical properties and yield of silage corn were analyzed. Soil bulk density was decreased in 3rd year at topsoil, but that decreased in 4th year at subsoil. Soil organic matter also decreased in 2nd year at topsoil, and decreased continuously at subsoil. Bulk density and hardness of soil depths showed significant negative simple correlation with dry matter yield and cation exchange capacity showed positive. Correlation coefficient of chemical properties with dry matter yield were low. The range of annual changes of moisture percent, hardness and organic matter were wider than the other properties. The significantly different of physical properties were higher than the chemical properties, and those of topsoil were higher than subsoil. According to multiple regression between yield and physico-chemical properties of subsoil, bulk density and cation exchange capacity were in the greatest contribution at the variations, but bulk density was greatest at the ratios.

• 한국작물학회지
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• 제45권2호
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• pp.88-92
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• 2000

Excessive soil water in paddy field induces growth losses during the vegetative stages of soybean plants. Our objectives were to know growth responses of soybean as affected by the level of ridge heights. A field experiment was conducted at the Research Farm of Korea University near Seoul in 1996. Ten cultivars of soybean (Glycine max (L.) Merrill) were planted at the ridge heights of 10, 30, and 50cm in paddy soil on 27 June. Total dry matter accumulation at the 10cm ridge height was severely decreased until the growth stage of R5 as compared to the ridge heights of 30 and 50cm, and this decrement was mainly due to both reduced leaf and stem dry weights. However, seed dry weight was not significantly decreased at the lower ridge height with the increment of harvest index. Cultivar differences were found on seed dry weight, crop growth rate from R1 to R5, and leaf/stem ratio of R5. From the above results, soybean growth responses to excessive soil water in paddy field were different between seed filling stage and late vegetative to early reproductive growth stages.

• 한국유기농업학회지
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• 제5권2호
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• pp.93-104
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• 1997

In order to investigate the growth response of grasses to chitosan solution amended soil were studied from the standpoint of estimating the growth stimulating adequate concentrations of chitosan solution amended soil in each grass. Three species in this experiment used were orchardgrass, tall fescue and reed canarygrass. Six different concentrations of chitosan solution amended soil were 0%(control), 0.01%, 0.05%, 0.1%, 0.5% and 1.0%, respectively. The resulte obtained were as follows ; 1. Leaf area(LA), dry weight of leaf(LW), dry weight of shoot(SHW), biological yield(BY), C/f ratio and T/R ratio were significantly different between species. 2. Growth stimulating effect by chitosan solution amended soil were found in plant length(PL) and T/R ratios of grasses. 3. Adequate concentrations of chitosan solution amended soil were different between species. The highest values of yield components and dry weight of plant parts were obtained at 0.01% in orchardgrass, 0,05% in reed canarygrass and 1.0% in tall fescue, respectively. 4. The growth response of grasses to chitosan solution amended soil were different between species. Thus, an increase in leaf area(LA) and dry weight of leaf(LW) by chitosan solution amended soil was mainly contributed to increase in dry weight of shoot(SHW) and biological yield(BY) in orchardgrass. Chitosan solution amended soil also stimulated growth of shoot and increased in biological yield(BY) in tall fescue. In reed canarygrass contributed to increase in C/F ratios. 5. Adequate concentrations of chitosan solution amended soil for an economical benefit of cultivation and dry matter production of grasses were ranged from 0.01% to 0.05% levels.

• 한국초지조사료학회지
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• 제18권3호
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• pp.251-258
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• 1998

To find out the effect of NPK-fertilization level and utilization method of pasture plants on the productivity of dry matter and nutrient of forages in hilly pasture, this experiment was arranged as a split block design with six treatments of 2 mainplots(N-$P_2O_5$-$K_2O$=210-150-180(wntrol), 280-200-240Kg/ha) and 3 subplots (cutting, grazing cutting+grazing alternative), and conducted at hilly land in Yeoju, Kyonggi Province 6om February, 1992 to October, 1993. In the treatment of grazing the early growth and cover degree of pasture plants wintered were more favorable. With increased NPK-application for two years, the average dry matter(DM) yield of 9,862kglha was incerased by 18% than that of the control, and the average DM yield of the cutting treatment of 10,434kaa was higher than that of others. In all treatments for two years, the average DM yield was composed of 94.0~95.1% grasses, 1.8~2.0% legumes and 2.8~4.2% weeds. The crude protein and energy productivity of forages in the treatment with increased NPK-fertilizer application increased by 20~23% than those of control, and those of cutting treatment were greatly increased than those of the grazing treatment. The average mineral content of forages in all treatments tended to be similar, Ca and Mg content and Ca/P ratio were slightly lower, and K content and K/(Ca+Mg) equivalent ratio of forages tended to be higher than the most desirable value of forages.

• 한국육종학회지
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• 제40권2호
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• pp.119-127
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• 2008

A total of 41 microsatellite markers were used with 29 genotypes to examine the relationship between SSR polymorphisms and N-use efficiency related traits with a goal to identify the putative QTLs related to these traits. These primers yielded a total of 183 alleles (average 4.46 alleles per primer), and polymorphism information content (PIC) values of the SSRs ranged from 0.119 to 0.805 with mean value of 0.425. Correlation coefficients were obtained among the four N-use efficiency traits in the 34 accessions and significant positive correlations of relative ratios between grain yield and harvest index (r=0.3404) and total dry matter (r=0.7976), while N uptake showed a moderate level of correlation with the ratios of the grain yield and total dry matter, respectively. 36.5% (15/41) SSR markers were monomorphic among the 25 japonica accessions out of the 29 accessions. Association between SSR genotypes and phenotypic performances from the total (29) or japonica (25) accessions was tested based on a single point analysis. Three putative QTL regions were detected for the ratio of grain yield. These include the chromosomal region containing the RM283 locus on chromosome 1 and RM25 on chromosome 8 (all and japonica accessions) and the region with the SSR marker, RM206 on chromosome 11 (the japonica accessions). For the total dry matter ratio, two chromosomal regions were identified as the putative QTL region. One is the region with the SSR marker, RM162 on chromosome 6 (all and japonica accessions) and the other was the one with the SSR marker RM25 on chromosome 8 (the japonica accessions). Among these markers, RM25 showed associations with both traits.

• 원예과학기술지
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• 제32권5호
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• pp.584-589
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• 2014

Jeffersonia dubia is a spring-flowering perennial found in rich forests in Korea and Northern China and has potential as an ornamental or medicinal plant. However, illegal picking and land use change have decreased the number of populations and overall population size of this plant in its natural habitat. Although J. dubia has been reported to be a shade-preferring plant, no study has determined the optimum light intensity for its growth. The objectives of this work were to observe the effects of various shading levels on the physiological responses of J. dubia and to determine the proper shading level for cultivation. Treatments consisted of four shading levels (0%, 50%, 75%, and 95% shade) imposed using black mesh cloth. The number of leaves and dry weight increased with decreased shading. The shoot-to-root ratio increased with increased shading, mainly due to decreased root dry weight under shading. Plants showed low net $CO_2$ assimilation rates and $F_v/F_m$ values combined with low dry matter levels when grown under 0% shade (full sunlight). These results indicate that J. dubia plants experience excessive irradiance without shading, resulting in damage to the photosynthetic apparatus. By contrast, the net photosynthesis rate increased as the shading level increased. $F_v/F_m$, the potential efficiency of PSII, was 0.8 under 95% shade, indicating that J. dubia is well-adapted under heavy shading. However, the low dry matter of plants in the 95% shade treatment indicated that the low light intensity under 95% shade led to a decline in plant growth. Thus, moderate light (50% shading) is recommended for cultivating J. dubia without physiological defects.

• 한국초지조사료학회지
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• 제16권1호
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• pp.75-80
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• 1996

The corn is one of the most important forage crop in Korea. The harvest time for silage affects dry matter (DM) yield and silage quality. This study was carried out to determine the effect of harvest time on the DM yield and nutritive value of corn forage at the Experimental Livestock Farm, College of Agriculture and Life Sciences, Seoul National University, Suweon in 1991. Forage DM yield and DM content of corn forage significantly increased mainly due to increase of ear. And also the ear to total DM ratio increased from 30% to 55% as the harvest was delayed. Chemical composition of the corn forage was improved by reduction in crude fihr, neutral detergent fiber and acid detergent fiber as the harvest was delayed. This results indicated that the harvest time of corn forage plays an important role to determine DM yield and DM contents for silage materials.

• 한국초지조사료학회지
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• 제15권1호
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• pp.61-66
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• 1995

연맥의 수확시 생육시기가 건물수량 및 사료적인 가치에 미치는 영향을 알기 위하여 1993년 3월 13일에 계명전문대학 부속목장에서 파종하여 지엽출현전, 지엽출현기, 출수기, 유숙기 및 호숙기에 수확하였다. 1. 사초의 건물함량은 지엽출현전, 지엽출현기, 출수기, 유숙기 및 호숙기에 각각 11.8, 12.3, 14.9, 25.6 및 28.8%로 지엽출현전부터 cnftnrlRK지는 낮았으나 출수기부터 호숙기까지는 급격히 증가되었다. 2. 잎의 비율은 지엽출현전의 58%에서 호숙기에는 11%로 생육이 진행된에 EK라 감소 되었고 이ㅗ영과 내영을 포함란 곡실의 비율은 출수기 7%에서 호숙기에는 43%로 증가 되었다. 3. 조단백질의 함량은 생육이 진행된에 EK라 감소(P<.05)되었고 그 범위는 24.9%에서 10.7%였다. 4. NDF의 함량은 생육이 진행된에 따라 출수기를 정점으로 증가(P<.05)되다가 유숙기에는 감소(P<.05)되었고 그 이후부터는 변화가 없었다. ADF의 함량은 출수기를 정점으로 증가(P<.05)되다가 유숙기부터는 감소(P<.05)되었다. 5, 건물수량은 지엽출현전, 지엽출현기, 출수기, 유숙기 및 호숙기에 각각 2,420, 4,380, 7,190, 13,130 및 14,530kg로 생육시기가 진행된에 EK라 증가(P<.05)되었다. 6. 본 시험의 결과에 의하면 봄 연맥의 사일리지 제조를 위하여 일시에 수확한다면 유숙기가 알맞다고 생각된다.