• Korean Journal of Organic Agriculture
• /
• v.6 no.1
• /
• pp.51-61
• /
• 1997

This experiment was carried out to investigate the growth response of 3 grasses to seed coating with chitosan solution and the attempt was made to estimate adequate seed coating concentrations of chitosan solution in each grass for the growth to be stimulated. Three species used in this experiment were orchardgrass, tall fescue and reed canarygrass. Six different seed coating concentrations of chitosan solution were applied as 0%(control), 0.01%, 0.05%, 0.1% and 1.0%, respectively. the results were obtained as follows; 1. Dry weight of tiller(WT), leaf area(LA), dry weight of leaf(LW), dry weight of stem(SW), dry weight of shoot(SHW), biological yield(BY) and C/F ratio were significantly different between species. 2. Number of tillers per plant(NT), dry weight of tiller(WT), dry weight of leaf(LW), dry weight of root(RW), dry weight of shoot(SHW), biological yield(BY) and T/R ration were significantly different between seed coating concentrations of chitosan solution. 3. The adequate seed coating concentrations of chitosan solution for the growth stimulating effect were different between species. The highest values of yield components and dry weight of plant parts were obtained at 1% in orchardgrass and tall fescue, and 0.05% in reed canarygrass, respectively. 4. Growth stimulating effect of seed coating in each species were different. The highest values were obtained in leaf area(LA), dry weight of leaf(LW), dry weight of root(RW), dry weight of shoot(SHW) and dry weight of biological yield(BY) in orchardgrass. The values of dry weight of stem(SW) and C/F ration were highest in reed canarygrass. 5. An increase in number of tillers per plant(NT), dry weight of leaf(LW), dry weight of stem(SW) and dry weight of root(RW) according to seed coating was attributed to the increase in dry weight of shoot(SHW). Among the aboved increasing factors, the dry weight of leaf(LW) was a main factor for the increase in dry weight of shoot(SHW). 6. An increase in dry weight of leaf(LW), dry weight of stem(SW) and dry weight of root(RW) according to seed coating was attributed to the increase in biological yield(BY). Both the dry weight of leaf(LW) and dry weight of root(RW) were main factors for the increase in biological yield(BY).

• Korean Journal of Organic Agriculture
• /
• v.4 no.1
• /
• pp.75-84
• /
• 1995

This study was carried out to find the effects of the mixtures of earthworm cast, peatmoss, and vermiculite as a vegetable plant growth medium on the growth pepper seedlings. The mixed ratios of earthworm cast-peatmoss-vermiculite were 40-20-40, 40-30-30, 40-40-40, 50-20-30, 50-30-20, 60-10-30, 60-20-20 and 60-30-10%. The results of the study are as follows: 1, There was a significant difference of plant length, leaf area, shoot dry weight, root dry weight and biological yield per plant for growth stages and mixed ratios(p<0.05). But there was no significant interactions for both of them. 2. The nursery soil with earthworm cast was generally higher than the control treatment in shoot dry weight, root dry weight adn biological yield per plant. The shoot dry weight and biological yield per plant were high in the treatment including 60% of the earthworm cast to the 3rd week and in the one including 50% from the 4th week. But in root dry weight, the treatment including 40% of it was higher than treatment of the others. 3. The shoot dry weight per plant in treatments consisting both of 40% of earthworm, 40% of peatmoss and 20% of vermiculite and of 60%, 10% and 30% was more significant than that in the control treatment(p<0.05). 4. The average relative growth rates of shoot dry weight, root dry weight and biological yield for all treatments were higher than the ratio of control treatment except the ration of the treatment consisting of 60% of earthworm, 20% of peatmoss and 20% of vermiculite.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.43 no.3
• /
• pp.161-167
• /
• 1998

Root and shoot development of two rice (Oryza sativa L.) cultivars with different genetic backgrounds was studied with reference to their relative growth. Tongil type (indica-japonica hybrid) cultivar 'Kuemkangbyeo' and japonica cultivar 'Koshihikari' were grown in $5000^{-1}$ a Wagnar pots under flooded condition. Three plants with roots of both cultivars were taken in every phyllochron through the heading stage to record morphological characteristics of shoot and root system. Compared to Koshihikari, Kuemkangbyeo produced more tillers and had greater shoot weight and leaf area per hill. Length and weight of the root system in both cultivars increased exponentially with time. At the same time, root system development was significantly faster in Kuemkangbyeo than in Koshihikari after the panicle initiation stage. As a result, Kuemkangbyeo has a vigorous root system which consists of larger number of nodal roots compared to Koshihikari. Also, the root length and weight per unit leaf area of Kuemkangbyeo were larger than those of Koshihikari in the later half of growing period, which suggests possible higher physiological activity of the root system of Kuemkangbyeo which is known as a high-yielding cultivar. The relationship between root traits (crown root number, total root length, and root dry weight) and shoot traits (leaf area and leaf+culm dry weight) in both cultivars closely showed allometry until the flag leaf stage.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.11 no.2
• /
• pp.90-96
• /
• 1991

This experiment was carried out in order to estimate the recovery days of root and stubble to the days after cutting, and contribution of specific stubble weight on the regrowth was examined using the relationships between the dry weight of shoot and yield components, and regrowth parameters by the days after cutting. The varieties examined were Maprima, Manhattan, Tove, Peramo, Caliente, Tempo and P-2 grown under individual plant basis. The results are may be summarized as follows: 1. Dry weight of root and stubble were recovered up to 13.5 and 11 days after cutting, respectively. 2. Dry weight of shoot(regrowth parts+stubble) was affected significantly by the varieties, stages of regrowth and variety x stage of regrowth. 3. The variety with tiller weight type showed higher average productivity of shoot than those of the variety with tiller number type. 4. Absolute growth rate(AGR) of shoot was correlated significantly with regrowth parts, stubble, root and weight of a tiller at the early stage of regrowth(up to 12 days after cutting), and correlated with regrowth parts, stubble, weight of tiller and stubble area at the late stage of regrowth(up to 20 days after cutting). 5. Contribution of specific stubble weight to absolute growth rate of shoot was different between the stages of regrowth. Thus, regrowth parts per specific stubble weight(RP1SSbW) and weight of tiller per specific stubble weight(WT1SSbW) contributed to absolute growth rate of shoot at the early stage of regrowth, and efficiency of specific stubble weight(ESSbW), regrowth parts per specific stubble weight (RPISSbW) and weight of a tiller per specific stubble weight(WT1SSbW) contributed to absolute growth rate of shoot at the late stage of regrowth. 6. Regrowth utilization rate(RUR) was one of the useful regrowth parameter to indicate the regrowth potential of grasses.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.47 no.6
• /
• pp.486-491
• /
• 2002

Spikelet number and its components of rice plant are closely associated with nitrogen accumulation and biomass production during panicle formation stage. To elucidate this relationship and also compare the differences of the sink formation efficiency among cultivars, spikelet number, its components, nitrogen content, nonstructural carbohydrate content, and plant dry matter were investigated under 5 nitrogen levels with two split application methods and shading treatments by using three rice varieties. The nitrogen amount in shoot at panicle initiation stage and at 15 days after panicle initiation showed significant positive correlation with primary rachis branches per square meter, and that at 15 days after panicle initiation and at heading stage with secondary rachis branches per square meter, Primary and secondary rachis branches per square meter showed positive significant correlation with the shoot dry weight at panicle initiation stage and at 15 days after panicle initiation stage, respectively, The amount of degenerated secondary rachis branches and spikelets per square meter showed significant negative correlation with the dry weight and nonstructural carbohydrate increase of stem during 15days after panicle initiation, and the contents of nonstructural carbohydrate at 15 days after panicle initiation. Spikelets per unit area showed significant positive correlation with nitrogen amount in shoot and shoot dry weight at heading stage. The sink formation efficiency expressed as the spikelet number produced by the unit amount of nitrogen in shoot at heading stage was higher in Nampoongbyeo than Choocheongbyeo and Hwaseongbyeo. Sink formation efficiency was negatively correlated with the dry weight increase of shoot and stem during reproductive stage. but not significantly with that of leaf in all varieties. Sink formation efficiency was not significantly correlated with nonstructural carbohydrate, but was significantly negatively correlated with structural carbohydrate increase during reproductive stage.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.47 no.5
• /
• pp.390-394
• /
• 2002

Spikelet number per unit area(SPN) is a major determinant of rice yield. Nitrogen nutrition status and biomass during reproductive stage determine the SPN. To formulate a model for estimating SPN, the 93 field experiment data collected from widely different regions with different japonica varieties in Korea and Japan were analyzed for the upper boundary lines of SPN responses to nitrogen nutrition index(NNI), shoot dry weight and shoot nitrogen content at panicle initiation and heading stage. The boundary lines of SPN showed asymptotic responses to all the above parameters(X) and were well fitted to the exponential function of $f(X)=alphacdot{1-etacdotexp(gamma;cdot;X)}$. Excluding the constant, from the boundary line equation, the values of the equation range from 0 to 1 and represent the indices of parameters expressing the degree of influence on SPN. In addition to those indices, the index of shoot dry weight increase during reproductive stage was calculated by directly dividing the shoot dry weight increase by the maximum value ($800 extrm{g/m}^{-2}$) of dry weight increase as it showed linear relationship with SPN. Four indices selected by forward stepwise regression at the stay level of 0.05 were those for NNI ($I_{NNI}_P$) at panicle initiation, NNI($I_{NNI}_h$) and shoot dry weight($I_{DW}_h$) at heading stage, and dry weight increase($I_{DW}$) between those two stages. The following model was obtained: SPN=48683ㆍ $I_{DWH}$$^{0.482}$ㆍ $I_{NNIp}$$^{0.387}$ㆍ $I_{NNIH}$$^{0.318}$ㆍ $I_{DW}$ $^{0.35}$). This model accounted for about 89% of the variation of spikelet number. In conclusion this model could be used for estimating the spikelet number of japonica rice with some confidence in widely different regions and thus, integrated into a rice growth model as a component model for spikelet number estimation.n.n.

• Journal of Bio-Environment Control
• /
• v.28 no.2
• /
• pp.104-109
• /
• 2019

The crops recommended for the plant factory system are diverse. The importance of planting density in the plant factory is being recognized. The objective of this study was to determine the optimal planting density for growth and quality of kohlrabi in a closed-type plant factory system. The kohlrabi was grown under fluorescent lamps and nutrient film technique system. The growth and quality of kohlrabi were investigated under four different planting densities ($22plants/m^2(15{\times}30cm)$, $27plants/m^2(15{\times}25cm)$, and $33plants/m^2(15{\times}20cm)$). There were no significant interactions between Shoot fresh and dry weights per plant or bulb stem fresh and dry weights per plant and planting density. Shoot fresh and dry weight per area or bulb stem fresh and dry weight per area were the highest at $33plants/m^2$. There were no significant interactions between plant height, leaf area, photosynthetic rate, hardness, and chlorophyll content and planting density. Significant differences in Bulb stem height and diameter, and brix were observed. Bulb stem height and diameter and brix of kohlrabi were the highest at $22plants/m^2$. Based on our results, we conclude that the optimal planting density is $33plants/m^2$ for growth of kohlrabi, however, the optimal planting density is $22plants/m^2$ for quality of kohlrabi in a closed-type plant factory system.

• Horticultural Science & Technology
• /
• v.32 no.2
• /
• pp.165-170
• /
• 2014

The objective of this study was to make growth and yield models of sowthistle (Ixeris dentata Nakai) by using an expolinear functional equation in a closed-type plant production system. The growth and yield of hydroponically-grown sowthistle were investigated under four different planting distances ($15{\times}10$, $15{\times}15$, $15{\times}20$, and $15{\times}25$ cm). Shoot dry weights per plant was the highest at $15{\times}25$ cm, but was the lowest at $15{\times}10$ cm. Shoot dry weights per area was the highest at $15{\times}15$ cm, but was the lowest at $15{\times}25$ cm. The optimum planting density and planting distance for yield of sowthistle were 44 plants/$m^2$ and $15{\times}15$ cm, respectively. Shoot dry weights per plant and per area were showed as an expolinear type functional equation. A linear relationship between shoot dry and fresh weights was observed to be linear regardless of the planting distance. Crop growth rate, relative growth rate and lost time in an expolinear functional equation showed quadratic function form. Radiation use efficiency of sowthistle was $4.3-6.1g{\cdot}MJ^{-1}$. The measured and estimated shoot dry weights showed a good agreement using days after transplanting as input data. It is concluded that the expolinear growth model can be a useful tool for quantifying the growth and yield of sowthistle in a closed-type plant production system.

• Horticultural Science & Technology
• /
• v.32 no.4
• /
• pp.493-498
• /
• 2014

The objective of this study was to make growth and yield models for common ice plant (Mesembryanthemum crystallinum L.) using expolinear functional equations in a closed-type plant production system. Three-band radiation type fluorescent lamps with a 12-hours photoperiod were used, and the light intensity was $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. Nutrient film systems with three layers were used for plant growth. Environmental conditions, such as air temperature, relative humidity and $CO_2$ concentration were controlled by an ON/OFF operation. Leaf area, shoot fresh and dry weights, light use efficiency of common ice plant as function of days after transplanting, accumulative temperature and accumulative radiation were analyzed. Leaf area, shoot fresh and dry weights per area were described using an expolinear equation. A linear relationship between shoot dry and fresh weights was observed. Light use efficiency of common ice plant was $3.3g{\cdot}MJ^{-1}$ at 30 days after transplanting. It is concluded that the expolinear growth model can be a useful tool for quantifying the growth and yield of common ice plant in a closed plant production system.

• Journal of Plant Biology
• /
• v.14 no.3
• /
• pp.21-28
• /
• 1971

Dry matter production, leaf area growth and total nitrogen changes were studied in Glycine max. soybean communities, which were grown in sandy loam soils controlled to provide various moisture levels, i.e., 5-7%(level 1), 8-10%(level 2), 11-13%(level 3), 14-15%(lev디 4), 17-20%(level 5) and 22-24%(level 6). A summary of the results is shown. The maximum dry matter production of leaves, stems and nodules and the maximum leaf area per unit area were at level 5, but the maximum of root dry matter production was at level 4. Total nitrogen content of the soybean plant decreased with growth, but each level of soil moisture content also showed a little difference. Water content of the plant decreased with plant age and soil water deficiency, especially in roots and nodules. Nodule formation increased in proportion to soil moisture content. total nitrogen content of the soil on which the soybeans grew, increased from 0.23% before sowing to 0.30% at 100 days after sowing. It seems that soil water content acts as a linear factor in the elongation or dry weight increase of shoots and roots until increasing to level 5. Considering the pattern of plant growth through analysis of the shoot and root dry weight ratio, or the photosynthetic organ and non-photosynthetic organ dry weight ratio, the asymptote of plant growth at a high soil water content exceeded that at a low soil water content.