• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.4
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• pp.226-231
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• 1992

This experiment was carried out to estimate the dry matter accumulation using growth analysis in spring growth of perennial ryegrass varieties grown under space planting conditions, based on the data of previous paper9'. The results obtained were as follows: 1. Growth parameters of leaf area ratio(LAR), specific leaf area(SLA) and leaf weight ratio(LWR) were recognized siginificant differences between varieties. But, specific leaf area(SLA), leaf weight ratio (LWR) and relative tiller appearance rate(RTAR) were recognized significant differences between growth stages. Specific leaf area(SLA) was significant difference for the interaction of variety Xgrowth stage. 2. The relative growth rate of biological yields(BYRGR) indicated significantly positive correlations with relative growth rate of shoot(RGR) and root(RWGR), and net assimilation rate(NAR) as affected by the varieties and growth stages. 3. The relative growth rate of biological yields(BYRGR) indicated significantly positive correlation with nct assimilation rate(NAR) in all varieties. Leaf area ratio(LAR) had significantly positive correlation with specific leaf area(SLA) in all varieties, but shows a significant negative correlation with leaf weight ratio(LWR) of Maprima variety. 4. The relative growth rate of biological yields(BYRGR) indicated significantly positive correlations with the absolute growth rates of yield components.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.1
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• pp.1-5
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• 2000

Leaf area is critical for crop light interception, and thereby has a substantial influence on crop yield. This experiment was conducted to characterize the development of soybean [Glycine max (L.) Merr.] leaf area. Plastochron index and leaf relative growth rate of Jackson was contrasted with the PI416937, which also has demonstrated tolerance to drought. First, plastochron ratio (PR) and plastochron index (PI) were evaluated in greenhouse to compare the leaf growth rate between two genotypes under well-watered condition. There was reasonable constancy of PR between two genotypes. The PR means of Jackson and PI416937 were 0.41 and 0.44, respectively. A fairly smooth increase of PI during vegetative stage was observed. Second, the relative growth rates were graphed against leaf area, normalized with respect to final leaf area, under well-watered and water-deficit conditions. Leaf growth was sustained longer in well-watered condition than water-deficit condition and there was a sizable proportion of leaves which was ceased earlier their growth in water-deficit condition compared to well-watered condition. The leaf relative growth rate of Jackson until leaves had completed at 45% of their growth during water deficit period was higher than that of PI416937.

• The Korean Journal of Ecology
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• v.21 no.4
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• pp.329-335
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• 1998

The growth of Phytolacca L. grown under three light regimes at three nutrient concentrations was analyzed. The effect of shading treatment on plnat growth was greater than that of nutrient treatment. Plant dry mass increased more than 5-fold during 21 days under 33% and 100% irradiances, whereas that was strongly reduced under 8% irradiance. Net assimilation rate decreased with plant growth irrespective of light and nutrient treatments, though the highest net assimilation rate was shown under 100% irradiance. Under 33% irradiance leaf area in plants supplied with nutrient solution increased to such extent as to compensate reduction in net assimilation rate, whic maintains almost identical growth rate with that under 100% irradiance. The relatonship between total plant nitrogen and leaf nitrogen content was dependent on the growth irradiance. Moreover, leaf nitrogen and specific leaf weight were also changed depending on the light and nutrient conditions. Based on these findings, it is suggested that the adaptive characteristics of Pokeberry plant to light and nutrient conditions may contribute to rapid extension of Pokeberry habital in Korea rocently.

• Asian Journal of Turfgrass Science
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• v.5 no.2
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• pp.95-114
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• 1991

This paper was designed to estimate the interaction of the first productivity, light conditions and to analyze the ecophysiological productivity, growth characteristics grown under various shading conditions in Zoysia japonica . The results summarized this experiment were as follows; 1.After transplanting the grass, increasing rate of leaf number and total leaf length was remarkahly high at the early growth stage in the control and the 30% shading plot. 2.The increasing rate of leaf area ratio (LA R) in all the experimental plot was remarkable high at the early growth stage after transplanting the grass. Especially, the control and 30% shading plot in compared with another plots, were remarkably high at rate of leaf area. 3.The length and the node number of rhizome in the control and 30% shading plot were also high and the difference was significantly large by the growth stage. 4.Chlorophyll content was very high at 36days after transplanting and then decreased. Increasing rate of shade resulted in its low content. The rate of chlorophyll a to b was decreased by in-creasing rate of shade. 5.The content of soluble sugar in the control and 30% shading plot was low at the early growth after transplanting and high at the late growth stage. Its content in the plot of 70% shading was remarkably low throughout the growth stage. 6.The increasing rate of standing plant in all the experimental plots was high at the early growth stage after transplanting. Increasing rate of shade was typically low through all the growth stage.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.2 no.2
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• pp.76-81
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• 2021

With continuous decline of Philippine forest cover, sustainable forest management and restoration are essential to restore destroyed forest ecosystems. Unfortunately, of ten most planted trees in reforestation projects in the Philippines, eight are exotic species, with large leaf mahogany (Swietenia macrophylla) being the most dominant. In this study, effect of Swietenia macrophylla in reforestation projects on native tree species was evaluated. Effects of S. macrophylla leaf litter, frequency, and canopy closure on the growth of the Philippine native species Pterocarpus indicus were investigated. Results showed that S. macrophylla leaf litter significantly inhibited the growth of P. indicus seedlings based on root collar-to-shoot height. The standardized growth rate of seedlings in plots without S. macrophylla leaf litter was significantly higher than the growth rate of seedlings in plots with leaf litter. Furthermore, there was no significant difference in the standardized growth rate of seedlings between plots without leaf litter and a control plot. On the contrary, S. macrophylla tree frequency and canopy closure showed no significant effect. These results attest to the negative effect of widely planted S. macrophylla to a valuable Philippine native tree P. indicus. With accumulating scientific evidence about negative effects of S. macrophylla on native trees, discontinued use in tree planting and reforestation efforts with active management of restoration sites previously planted with large leaf mahogany are needed.

• Journal of Ecology and Environment
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• v.29 no.5
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• pp.461-467
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• 2006

The growth pattern and the seasonal changes in nutrient contents of Humulus japonicus were investigated. Stem length of H. japonicus reached the maximum from 240 to 260 Julian date and the median value was found at 255 Julian date. The maximum leaf area was observed from 235 to 248 Julian date and the median value was at 240 Julian date. The maximum growth rate of the stem length ranged from 205 to 227 Julian date. The leaf area showed the maximum growth rate from 196 to 214 Julian date. The median date in the growth rate of the stem length and leaf area was 212 and 205 Julian date, respectively. The growth rate of H. japonicus was related to rainy season and precipitation. Phosphorus and sodium contents of H. japonicus were correlated with maximum potential rate of relative growth. Although stem biomass of H. japonicus was $ 1.5{\sim}3.5$ times larger than that of leaf, N content of the leaf ($4.48{\sim}5.27%$) was about 2 times higher than that of the stem ($2.00{\sim}3.62%$). High content of N might be responsible for the high growth rate of H. japonicus in summer. This result provides valuable information for appropriate timing for the removal of H. japonicus.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.4
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• pp.373-381
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• 1999

Six soybean cultivars having different SDS susceptibility were planted with sorghum seedinoculum infested with F. solani isolate 171 in the greenhouse. First leaf symptoms appeared on unifoliar leaves at 9 days after inoculation and all cultivars showed the typical leaf symptoms at 13 days after inoculation, when trifoliar leaves emerged. Leaf symptoms development in susceptible cultivars was faster than in resistant cultivars. Leaf symptom severities during the period of 25 to 29 days after inoculation showed a significant difference between cultivars which had SDS resistance and sus ceptibility. In this period, area under the diseaseprogress curve (AUDPC) of Hartz 6686 was the highest and that of PI 520733 was the lowest. SDS caused serious damage to the growth of soybean in all cultivars. Average reductions of growth rate of root fresh weight and dry weight were greater than those of plant tops. Duyu-kong showed less severe leaf symptoms than that of SDS suscetible cultivars; however, average growth rate of plants top and roots of this cultivar was less but not significantly different than those of SDS susceptible cultivars. In all cultivars, as severity of leaf symptoms increased, plant top weight decreased. Root rot symptoms were observed in all cultivars before leaf symptoms appeared. Average proportions of tap root reddish-brown discoloration of all cultivars was up to 75 % at 15 days after inoculati on; however there was no significant differenc between cultivars at each rating date. Appearances of leaf symptoms on leaves varied in each cultivar. SDS resistant cultivars had a significantly higher level of crinkling than susceptible cultivars and SDS susceptible cultivars had a significantly higher level of necrosis than resistant cultivars. Further study will be needed to identify the relationships between the physiological growth rate and SDS severities in soybeans.

• Asian Journal of Turfgrass Science
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• v.13 no.1
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• pp.1-20
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• 1999

This study was carried out to investigate the interaction between productivity and light condition and to analyze the material productivity and productive charactaristics under different hours of light in Zoysia japonica. 1. Rate increasement of leaf number and total leaf length was remarkably high at the early growth stage in the control and 9 hour light treatment. The rate gradually decreased as growth proceeded. But 3 hour treatment was very low in the rate from its early growth stage through the whole test period. 2. The increasing rate of leaf area ratio (LAR) in all the experimental plots was remarkably high at the early growth stage after transplanting the grass. The shorter photoperiod resulted remarkable lower increasement of LAR. 3. The rhizome growth rate of the 9 hour photoperiod was high contrast to the 3 hour photoperiod treatment. The increasing rate of node number was also showed similar trend. 4. Chlorophyll content was very high at the 36 days after transplanting and then decreased gradually. Chlorophyll content on 3 hours photoperiod plot severely decreased. The ratio of chlorophyll a to b was decreased significantly at short day treatment. 5. The content of soluble sugar was increased at shorter photoperiod. The highest ratio of sugar content was on August, 28 by HPLC method. Such a result was attributed to accumulation of sugar in spite of low synthesis of ploysacchrides, translocation by low consumption. 6. The increasing rate of standings in all light treatment was high at the early growth stage after transplanting. Short photoperiod treatment by 3hour showed especially low prganic productivity on Zoysia japonica.

• Journal of the Korean Society of Tobacco Science
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• v.4 no.2
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• pp.41-50
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• 1982

To investigate tile effects of growth characteristics on the yield, price per Kg, chemical contents and physical properties in Burley tobacco, ten varieties including Burley 21 were tested in this study. The results obtained are summarized as follows. 1 Forty to fifty days after transplanting, CCR (Crop Growth Rate) was the highest. RCR (Relative Growth Rate) increased up to 40 days, but decreased 50 days when maturation began. High- yielding varieties showed high CCR and RCR till 60 days. 2. Total alkaloid content of cured leaf increased about three times than that of topping stage, but the increased rates were some what different among varieties. 3. Leaf area, stalk diameter, stalk height and days to flower showed positive correlations to yield, whereas leaf thickness and weight per unit leaf area showed negative. 4 Varieties which are high in cured leaf weight ratio and weight per unit leaf thickeners showed relatively poor quality. 5 Nitrogen content was high in leafy and larger stalk diameter variety. 6. There are positive correlation between weight per unit leaf thickness and filling power. The time of combustion was positively correlated to leaf thickness and weight Per unit leaf. 7. It can be concluded that many characteristics are related to the yield, but not quality. It is, there fore, easy to Predict tile yield, but difficult to forecast the qualiffy.

• The Korean Journal of Ecology
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• v.17 no.4
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• pp.453-461
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• 1994

Size class structure and vegetative growth of a perennial herb of the temperate deciduous forests, Symplocarpus renifolius Schott, were studied from 1991 to 1994 in Namhansansung, Kyonggi Province, Korea. The size class structures of leaf number and leaf area per individual followed bell-shape curve, i.e. frequency of middle class was relatively high. The leaf area increased from the late-March to mid-May. At the end of the growing season, leaf area(length X breadth) was proportional to biomass, especially aboveground biomass. The leaf number and leaf area per individual increased at the rate of 0.08 leaf/year and 9.7 $cm^2/year$, respectively. The size of the individuals in large-sized classes, in leaf number and leaf area, decreased in next year, while the size of the individuals in small-sized classes increased. Therefore, it was concluded that the size class structure of S. renifolius population was largely determined by the growth form.