• Asian-Australasian Journal of Animal Sciences
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• v.25 no.9
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• pp.1237-1247
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• 2012

The objective of this study was to evaluate the predictions of dry matter intake (DMI) and average daily gain (ADG) of Vietnamese Yellow (Vang) purebred and crossbred (Vang with Red Sindhi or Brahman) bulls fed under Vietnamese conditions using two levels of solution (1 and 2) of the large ruminant nutrition system (LRNS) model. Animal information and feed chemical characterization were obtained from five studies. The initial mean body weight (BW) of the animals was 186, with standard deviation ${\pm}33.2$ kg. Animals were fed ad libitum commonly available feedstuffs, including cassava powder, corn grain, Napier grass, rice straw and bran, and minerals and vitamins, for 50 to 80 d. Adequacy of the predictions was assessed with the Model Evaluation System using the root of mean square error of prediction (RMSEP), accuracy (Cb), coefficient of determination ($r^2$), and mean bias (MB). When all treatment means were used, both levels of solution predicted DMI similarly with low precision ($r^2$ of 0.389 and 0.45 for level 1 and 2, respectively) and medium accuracy (Cb of 0.827 and 0.859, respectively). The LRNS clearly over-predicted the intake of one study. When this study was removed from the comparison, the precision and accuracy considerably increased for the level 1 solution. Metabolisable protein was limiting ADG for more than 68% of the treatment averages. Both levels differed regarding precision and accuracy. While level 1 solution had the least MB compared with level 2 (0.058 and 0.159 kg/d, respectively), the precision was greater for level 2 than level 1 (0.89 and 0.70, respectively). The accuracy (Cb) was similar between level 1 and level 2 (p = 0.8997; 0.977 and 0.871, respectively). The RMSEP indicated that both levels were on average under-or over-predicted by about 190 g/d, suggesting that even though the accuracy (Cb) was greater for level 1 compared to level 2, both levels are likely to wrongly predict ADG by the same amount. Our analyses indicated that the level 1 solution can predict DMI reasonably well for this type of animal, but it was not entirely clear if animals consumed at their voluntary intake and/or if the roughness of the diet decreased DMI. A deficit of ruminally-undegradable protein and/or a lack of microbial protein may have limited the performance of these animals. Based on these evaluations, the LRNS level 1 solution may be an alternative to predict animal performance when, under specific circumstances, the fractional degradation rates of the carbohydrate and protein fractions are not known.

• Korean Journal of Soil Science and Fertilizer
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• v.14 no.4
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• pp.195-200
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• 1982

Fused phosphate and slag have used as a sources of phosphate and silicate fertilizers. In order to find out effects of these fertilizers on the growth of young rice plants in nursery, relationships between dry matter production and nutrient uptake at different fertilizer application rates were investigated for two rice varieties, Milyang 23 (a Indica-Japonica hybrid) and Akibare (a Japonica). The results were summarized as followers; 1. The maximum dry matter production was obtained at 75-150 kg/10a of fused phospate and 100-200 kg/10a of slag, respectively, however, a some variations between varieties were recognized. 2. The top/root ratio of varieties around 1.0 was proper for healty see dings and this ratio was reached at application of 75 kg/10a of fused phosphate and 200 kg/10a of slag. 3. The efficiency of applied silicate of rice seedlings was higher in fused phosphate than in slag. 4. The growth of seedling was severely retarded when soil pH was increased above 7 by the application of more than 225 kg/10a of fused phospahte and 400 kg/10a of slag.

• The Korean Journal of Ecology
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• v.21 no.5_3
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• pp.649-663
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• 1998

The clarify the ecological properties, and to predict change of understory vegetation of mt. Nam Park, population dynamics and interspecific competition of D. smilacinum and D. viridescens, which grow in understory of deciduous broad-leaved forest and pseudo-annuals, were studied from May 20 to May 30 1998. The depth of litter layer, soil moisture content, soil organic matter and soil texture were surveyed in 18 populations (15 D. smilacinum populations and 3 D. viridescens populations). Mean litter layer of d. smilacimum population was thinner than that of D. viridescens populations). Mean litter layer of D. smilacnum population was thinner than that of D. viridescens population. The contents of soil moisture and organic matter of D. smilacinum population were lower than that of D. viridescens population. The D. smilacinum growed in broad range of soil texture but D. viridescens in loamy soil. Because D. smilacinum could tolerate more broad range of soil moisture and soil texture than D. viridescens, the former covered the herb layer in earlier stage and the latter introduced in later stage when rhizome could grow easily. The numbers of individual in two marginal parts were smaller than that in center in same D. smilacinum patch. And the total numbers of individuals grown in (10 ${\times}$ 10)cm were from 0 to 12. The rhizome (subterranean runner) weight, rhizome length, root weight, shoot weight, lea weight and leaf number per subquadrat (cell) increased along the number of individual, that is, increased from marginal part to center. But rhizome weight and rhizome length per individual were vice versa. Therefore, the individuals in marginal part reproduced longer and stronger asexual propagules than that in center. The distribution pattern of D. smilacinum was contageous and that of D. viridescens was random or regular. Therefore, population growth of former was independent on density and that of latter was dependent on density. The distributions of size-class showed normal curves in two population, but the curves based on data of total dry weight showed positive skewness and those of leaf number showed negative skewness The correlation coefficient (CC) values between the properties of each organ were high in two population and significant at 0.1% level. The CC values of D. viridescens were higher of the two. Therefore, the former allocated the energy to each organ stable. The rhizome depth of d. viridescens was 2 times deeper than that of D. smilacinum. And rhizome length and weight of D. viridescens were longer (2 times) or heavier (4 times) than those of D. smilacinum. The patch size of D. viridescens increased 60 cm per year and that of D. smilacinum 30 cm. On this results, the intrinsic increase velocity of d. viridescens patch was 2 times faster than that of d. smilacinum, therefore, on the competition, the former had an advantage over D. smilacinum. The reason why d. viridescens defeated D. smilacinum resulted from that the leaf area of former was 4 times broader than that of latter. in Mt. Nam Park, it was thought that two disporum Population would change with the 3 thpes of environmental change as followings. First, no human impact and increase of soil moisture content resulted in increase of D. viridescens population. Second, mild human impact and similar condition of soil moisture content resulted in slow increase or no changes of D. smilacinum and d. viridescens population. Third, severe human impact and dry condition resulted in decrease or vanishment of two disporum populations.

• Journal of Bio-Environment Control
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• v.26 no.3
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• pp.167-174
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• 2017

To identify the appropriate irrigation level for Pinus densiflora, a common reforestation species in Korea, we investigated their growth response characteristics according to different irrigation treatment levels for producing container seedlings with relatively high growth rate for higher survival rate when planted at the reforestation site. The container seedlings including control seedlings (no irrigation was applied) were grown in 104-cell trays were irrigated for 8 weeks from 15 weeks after seeding, at intervals of 1, 2, 3, 5, 7, 10, and 15 days. Analysis of the height growth, root collar diameter growth, and dry matter production of the container seedlings according to irrigation showed that the highest growth reaction was observed for the irrigation interval of 1 day. A shorter irrigation cycle resulted in better growth of the container seedlings, but overall, longer total root length were observed with an irrigation cycle of 3 days compared with cycles of 1 or 2 days. Quality index (QI) was the highest for the irrigation interval of 1 day, and tended to decrease with increase in the irrigation interval. Thus, it was determined that irrigation at intervals of 1-2 days was appropriate for growing Pinus densiflora container seedlings.

• Journal of The Korean Society of Grassland and Forage Science
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• v.40 no.4
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• pp.227-235
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• 2020

This study was conducted to investigate the growth characteristics of the shoot and roots and to analyse the morphological characteristics of roots of waterlogging resistant and susceptible maize inbred lines. Six maize inbred lines were treated with waterlogging for 10 days at V3, and the degree of leaf senescence was evaluated for waterlogging resistance. As a result of waterlogging resistance evaluation, KS85 was the most damaged inbred line with 3.33 senescence leaves and 5.54 degree, and KS141 was the least damaged inbred line with 1.33 senescence leaves and 3 degree. At 20 days after treatment, the effect of waterlogging stress on the shoot dry matter accumulation of KS85 and KS141 were decreased by 86.1% and 77.0%, respectively, compared to the control. Similarly, root dry matter accumulation of KS85 and KS141 were decreased by 77.6% and 65.0%. As a result of SEM photographs of the nodal roots of the two maize inbred lines, the thickness of cortex of KS141 was thicker than that of KS85, and the distortion of the cortex was observed in KS85 at 20 days after waterlogging. It was concluded that the thickness of cortex was related to maize waterlogging resistance.

• Journal of Korean Society of Forest Science
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• v.11 no.1
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• pp.1-24
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• 1970

This experiment was carried out to elucidate the behavior of nutrition absorption and the acid tolerance, on varying soil pH levels, of Pinus thunbergii, Pinus densiflora, Pinus rigida, PInus koraiensis, Larix leptolepis and Abies holophylla which are 6 month old seedlings through examinations of the absorption behavior, the acid and alkali tolerance of N,P,K, Ca and Fe in the sand culture media with artificially controlled pH. 1. The increase rate of dry matter conditioned by the behavior of nutrition absorption in a strong acidic condition (pH3) was found in the following decreasing order of Pinus rigida, Pinus thunbergii. This order, therefore, can also be said to apply to the case of acid tolerance. 2. The increase rate of dry matter in a strong alkaline condition (pH9) was found in the following decreasing order of Pinus thunbergii, Pinus rigida, Pinus densiflora, Pinus koraiensis, Abies hoplohylla, Larix leptolepis. This order, therefore can be said to apply to the case of alkali tolerance. 3. Considering the absorption behavior of K and Ca, it is possible to decide the tolerance of acid from the absorption behavior and it can be said that if the absorption quantity is K>Ca the acid tolerance is strong and vice versa. 4. Considering the ratio of K:Fe and Ca:Fe in this experiment, a strong acid tolerance shows a higher ratio of K/Fe and vice versa. And also a strong acid tolerance shows a lower ratio of Ca/Fe and vice versa. It is therefore possible to decide the acid tolerance from the absorption behavior of K, Ca and Fe. 5. Of the tree species subjected to this experiment, Pinus thunbergii was the strongest in both acid and alkali tolerance. 6. In spite of that in all species the dry weight in the root is smailer than that in the top, the quantity of Fe contained in the root was larger than that in the top.

• Korean Journal of Medicinal Crop Science
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• v.6 no.2
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• pp.131-136
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• 1998

This experiment was carried out to investigate the effect of several organic fertilizers on the growth and root yield of Achyranthes japonica N. from 1995 to 1996. Four organic fertilizers were applied: rice straw manure (RSM), fermented rice straw manure (FRSM), mixed oil cake manure (MOCM) and mighty soil manure (MSM). Organic matter, available phosphate, $K_2O$, CaO, and MgO of soil increased in all plots with the addition of organic fertilizers, specifically with MOCM application. The highest contents of total nitrogen were 6.16% for MOCM and the available phosphate contents were very high in all of organic fertilizers except MSM. RSM and MSM with C/N ratios of 22.5, 17.7, respectively, were easily decomposed but C/N ratios of FRSM and MOCM, which were considered as irresolvable organic fertilizers, were 40.9 and 8.4, respectively. FRSM and MOCM applications increased emergence rate and improved the growth characters of shoot and root parts of plants compared to those of N - P - K fertilization. The highest dry root yield resulted from FRSM 20% and MOCM 26% treatment. There were significantly positive correlations between the growth characters of shoot, root parts of plants and dry root yield in A. japonica grown under organic fertilizer applications.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.3
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• pp.221-227
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• 1989

This study was conducted to understand the influence of soil compaction on root growth and nutrient uptake characteristics of the soybean roots grown in two soils with different texture. Tap root elongation was measured on young seedling grown in cores compacted to different bulk densities of 1.2, 1.4 and $1.6/cm^3$ with different soil water retention in laboratory. The soil used were Samgag sandy loam and Baegsan loam soils. The wet and dry weight, total length, average radius and total surface area of roots were measured on soybean plants grown in 1/5000 a Wagner pots compacted to different bulk density of 1.2 and $1.4g/cm^3$. The nutrient uptake of soybean shoot was measured and evaluated with the unit surface area of roots at the 7th, 17th and 27th days after germination. The results were as follows: 1. The tap root elongation rate was faster in the loam soil with low bulk density than in the sandy loam soil with high bulk density. The elongation rates were remarkedly decreased when soil water was lower than the retention of 4 bars in loam soil and that of 1 bars in sandy loam soil. 2. Tap root elongation rate sharply decreased as increased soil strength higher than $2kgf/cm^2$ measured by ELE penetrometer showing curvillinear regression. However, it was low regardless of soil strength when soil water retention was 10 bars in sandy loam soil. 3. From the pot experiment, the total length of roots were longer in loam soil than in sandy loam soil and was longer in the soils with lower bulk density. The average radius of fine roots grown in sandy loam soil was larger than that grown in loam soil. The total surface area of roots was greater in the loam soil with low bulk density than in the sandy loam soil with high bulk density as the total length of roots. 4. The amounts of nutrient uptake by soybean shoots were greater in loam soil primarily due to more production of dry matter than in sandy loam soil. The nitrogen influx rates through the unit surface area were 597 to $753nmoles/day-cm^2$ in loam soil and 222 to $365nmoles/day\;cm^2$ in sandy loam soilshowing higher value in higher bulk density. The potasium influx rates were 99 to $175nmoles/day-cm^2$, and those of phosphate were 26 to $46nmoles/day\;cm^2$. Those of Ca and Mg were 175 to 246 and 163 to $205nmoles/day\;cm^2$. The difference in nutrient influx rates between bulk densities of these elements were lower than that of nitrogen.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.6
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• pp.965-972
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• 2020

Objective: Astragalus membranaceus root is a well-known traditional Chinese herbal medicine with many biological active constituents. This study was conducted to examine the effects of Astragalus membranaceus root powder (AMP) on growth performance, serum antioxidant and immune response in finishing lambs. Methods: A total of thirty-six Guangling fat-tailed ram lambs (body weight = 19±2 kg, mean±standard deviation) were randomly assigned to one of six treatments for a 40 d feeding period, with the first 10 d for adaptation. Treatments consisted of the lambs' basal diets with addition of 0, 5, 10, 15, 20, and 30 g/kg of diet of AMP. Results: Response to supplementation level of AMP was quadratic (p≤0.032) for final weight and ADG with the greatest at 10 g/kg of diet, but dry matter intake was not affected (p≥0.227) by treatments. The increase of AMP supplementation resulted in a quadratic response in contents of triglyceride and creatinine (p<0.05), with the lowest values for 10 and 20 g/kg of diet, respectively. A linear and quadratic decrease was observed in activity of alkaline phosphatase in serum of lambs. As the AMP supplementation increased, the activities of total superoxide dismutase and total antioxidant capacity increased linearly (p≤0.018) and hydroxyl radical (OH^-) decreased linearly (p = 0.002). For catalase (CAT) and malondialdehyde (MDA), quadratic (p≤0.001) effects were observed among treatments, with the greatest CAT and lowest MDA values at 10 g/kg AMP. Additionally, supplementing AMP up to a level of 10 or 15 g/kg of diet quadratically increased immunoglobulin and interleukin contents in the serum. Conclusion: The results indicated that AMP can be used as natural feed additive in the ration of lambs to improve ADG, antioxidant status, and immune functions, and the optimal dose was 10 g/kg of diet under the condition of this experiment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.3
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• pp.188-193
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• 2004

Fifty-day-old plug seedlings of yacon (Polymnia sonchiflolia Poeppig ＆ Endlicher) were transplanted on Mar. 23, Apr,8, Apr,23, May 8, May 23, and June 7,2002 at Jeju to evaluate the effect of transplanting date on the growth and yield of yacon in Jeju island. Delaying the transplanting until May 23 greatly decreased plant height stem height, main stem diameter and number of nodes per plant. The number of marketable tuberous roots was about 6.0 per plant with the early transplanting from March 23 to April 231 but decreased to 1.9 per plant with the latest transplanting time, June 7. The yield of marketable tuberous roots of early transplanted (March 23 to April 23) yacon was about 27 MT/ha, and was 32.4 MT/ha at April 23 transplanting, but was remarkably reduced at the three later transplantings, May 8, May 23, and June 7. Dry matter and soluble solid contents of marketable tuberous roots were 14％ and 15％, respectively, regardless of transplanting date. The weight of a marketable tuberous root ranged from 153 to 183.9 g at the first three transplantings, but gyeatly reduced with delaying transplanting until May 7. The optimum transplanting date for yacon in Jeju island seems to be from mid-April to late April considering tuberous root yields, the risk of late-spring frost, and cost of seedling raising.