• Asian Journal of Turfgrass Science
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• v.24 no.1
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• pp.16-23
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• 2010

Mowing is an important practice in golf course management. Mowing interval and height can affect net photosynthesis of turfgrass and finally shoot density, tillering, rooting and regrowth of turfgrass. The objectives of this study were to investigate the regrowth rate of zoysiagrass shoot under different mowing height for determination of proper mowing frequency. Recommended mowing interval were calculated by a rule that no more than 33% of the above ground height be removed in a single mowing. Daily shoot growth of zoysiagrass at 10 mm mowing height were 2.1~4.7 mm (July), 1.9~2.9 mm (August), 0.9~1.5 mm (September), and 0.6 mm (October). These results indicate that recommended mowing interval were 1.1~2.3 day for July, 1.7~2.4 day for August, 3.5~5.4 day for September, and 8.5 day for October, respectively. Daily shoot growth of zoysiagrass at 15 to 17 mm mowing height were 4.0~5.3 mm (July), 2.9~4.5 mm (August), 1.4~3.7 mm (September), and 1.3 mm (October). These results indicate that recommended mowing interval were 1.4~1.9 day for July, 1.7~2.5 day for August, 2.3~6.3 day for September, and 6.8 day for October, respectively. Daily shoot growth of zoysiagrass at 18 to 21 mm mowing height were 3.5~4.7 mm (July), 2.9~4.9 mm (August), and 1.5~1.8 mm (September). These results indicate that recommended mowing interval were 1.9~2.6 day for July, 1.8~3.1 day for August, and 5.9~7.0 day for September, respectively. Daily shoot growth of zoysiagrass at 50 mm mowing height were 4.6~4.9 mm (July), 5.0~6.5 mm (August), and 2.5~4.7 mm (September). These results indicate that recommended mowing interval were 5.1~5.4 day for July, 3.9~5.0 day for August, and 5.3~9.8 day for September, respectively.

• The Korean Journal of Ecology
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• v.17 no.1
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• pp.59-67
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• 1994

Differences in physicochemical characteristics of sediment and changes in density, height and dry matter of shoots along different water depths were investigated in the stands of Zizania latifolza populations of the littoral zone of Lake Paltangho, Korea. Any significant differences in sediment chemistry were not found along water depth, although sand content decreased slightly with increasing depth. Shoot density of Zizania latqolia decreased with increasing water depth. In shallower water, many of the short shoots died in the early growth stages. The morphology of shoots was taller and heavier in deeper water. The distributions of shoot heights became negatively skewed and leptokurtic as plants grew, and these changes occurred in the earlier growth stages in deeper water. The standing crop of shoots increased with increasing water depth. These results suggest that Zizania lattfolia has a growth strategy for adjustment to deep water through decreasing shoot density and increasing height.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.326-331
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• 2018

Crop growth models are useful tools for understanding and integrating knowledge about crop growth. Models for predicting plant height, net photosynthesis rate, and plant growth of quinoa (Chenopodium quinoa Willd.) as a leafy vegetable in a closed-type plant factory system were developed using empirical model equations such as linear, quadratic, non-rectangular hyperbola, and expolinear equations. Plant growth and yield were measured at 5-day intervals after transplanting. Photosynthesis and growth curve models were calculated. Linear and curve relationships were obtained between plant heights and days after transplanting (DAT), however, accuracy of the equation to estimate plant height was linear equation. A non-rectangular hyperbola model was chosen as the response function of net photosynthesis. The light compensation point, light saturation point, and respiration rate were 29, 813 and $3.4{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, respectively. The shoot fresh weight showed a linear relationship with the shoot dry weight. The regression coefficient of the shoot dry weight was 0.75 ($R^2=0.921^{***}$). A non-linear regression was carried out to describe the increase in shoot dry weight of quinoa as a function of time using an expolinear equation. The crop growth rate and relative growth rate were $22.9g{\cdot}m^{-2}{\cdot}d^{-1}$ and $0.28g{\cdot}g^{-1}{\cdot}d^{-1}$, respectively. These models can accurately estimate plant height, net photosynthesis rate, shoot fresh weight, and shoot dry weight of quinoa.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.1
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• pp.1-7
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• 2014

The objective of this study was to determine the effect of single and co-inoculation of plant growth promoting bacteria (PGPB) on early plant growth in Saemangeum reclaimed soil. Plant growth promoting Brevibacterium iodinum RS16 and Methylobacterium oryzae CBMB20 were inoculated on maize (Zea mays L.) and sorghum-sudangrass hybrid (Sorghum bicolor L.) grown in Saemangeum reclaimed soil. Single and co-inoculation of B. iodinum RS16 and M. oryzae CBMB20 increased plant height, dry biomass accumulation and macro-nutrient accumulation of maize and sorghum-sudangrass hybrid. M. oryzae CBMB20 treatment increased plant height in maize by 41.2% at 30 days after sowing (DAS), shoot dry weight and total dry weight compared to non-inoculated treatment. Macro-nutrient accumulation (N and P) in maize roots was significantly increased with co-inoculation treatment, K and Ca content was significantly increased at B. iodinum RS16 treatment compared to non-inoculated treatment. Macro-nutrient accumulation (P, K, Ca and Mg) in shoot was higher with M. oryzae CBMB20 treatment compared to non-inoculated treatment. In case of sorghum-sudangrass hybrid, co-inoculation treatment showed 33.7% increase in plant height compared to non-inoculated treatment at 30 DAS. M. oryzae CBMB20 treatment increased root dry weight and total dry weight, macro-nutrient accumulation in roots and N, Ca and Mg accumulation in shoot compared to non-inoculated treatment. P and K accumulation in shoot was significantly increased at co-inoculation treatment compared to non-inoculated treatment. This pot culture experiment demonstrated that single and co-inoculation of B. iodinum RS16 and M. oryzae CBMB20 increased the early growth and nutrient accumulation of maize and sorghum-sudangrass hybrid.

• Korean Journal of Applied Biomechanics
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• v.15 no.4
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• pp.55-66
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• 2005

The present study used a video analysis system to quantify the kinematical data of step shoot motion by male university handball players. From the results of analyzing dynamic variables of step shoot motion according to shooting direction were drawn conclusions as follows. 1. The height of release was proportional to the height of players, and the height of release appeared low in left-side attacks. This is probably because the left-right-throwing angle is larger in left-side attacks than that in center attacks and right-side attacks and, as a result, the throwing arm is lowered down in throwing. 2. The leftward inclination angle of the body was larger in order of right-side attacks > center attacks > left side attacks. 3. Players' throwing form was close to three quarter style in left-side attacks. In center and right-side attacks, the arm was somewhat more upright but still it was more three quarter style than overhand style. 4. The front-rear throwing angle at the moment of release was much higher in right-side attacks than in left-side ones. This is probably because the point of time for releasing the ball is usually late in right-side attacks and, as a result, the front-rear throwing angle becomes quite large. 5. The contribution of body parts on the ball speed was higher in order of the forearm > upper arm, hand > shoulder joint. 6. In players whose distance between the two legs at the moment of release, their body usually did not incline to the side much. Thus it is considered necessary to correct the right leg in their shooting motion. 7. According to the result of analyzing throwing form, the speed of the ball at the moment of leaving the hand was faster in right-side attacks than in left-side and center attacks.

• FLOWER RESEARCH JOURNAL
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• v.17 no.3
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• pp.185-189
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• 2009

This study was carried out to investigate the effect of shading (50% or not) and pruning height (3cm, 6cm, and 9cm) of remained above-ground plant part on shoot emergence aspect, mortality rate, flowering and cut flower characteristics of two years old Gypsophila paniculata plants. Days to shoot emergence (80%) advanced, emerged shoot number increased and mortality rate surveyed on late October decreased in 50% shading treatment. In addition to, mortality rate decreased, as above-ground plant part was highly pruned. Blooming was earlier with highly pruning the remained above-ground pan and under non-shading condition than shading. Growth traits such flower stalk length, primary branches number, stem diameter, and cut flower yield were the best and also non-particulate rate and rosette formation rate were the lowest in pruning height of 9cm under non-shading condition.

• Korean Journal of Plant Resources
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• v.26 no.6
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• pp.709-717
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• 2013

The objective of this study was to examine the effect of root pruning intensity in combination with different initial seedling size on the growth of transplanting seedlings of Quercus acutissima. One-year-old seedlings were divided into three groups depending on their height, i.e. small (< 15 cm), medium (25-35 cm) and large size (35 cm <). Root of seedlings was pruned by three intensity such as, leaving 5 cm (severe), 10 cm (medium) and 15 cm (light) of taproot from the root-collar. After one year, we investigated survival rate, height and root-collar diameter (RCD) increment and final shoot dry weight. Also we measured characteristics of newly developed lateral roots such as number, total length, dry weight and diameter. Severe root pruning showed the lowest survival rate in all seedling size. Height increment, RCD increment and shoot dry weight were decreased with increasing intensity of root pruning. Seedlings of medium and light root pruning showed similar above-ground growth and dry weight of lateral roots. More large seedlings showed good survival rate, height increment and final shoot dry mass in all root pruning intensity. Therefore, one-year-old seedlings of Q. acutissima should be pruned taproot by 10 cm and transplanted to obtain excellent performance and increase the efficiency of transplanting work. Based on the findings of this study, it is important that applying to different root pruning intensity depending on initial seedling size for producing 2-year-old seedlings with excellent growth and high quality.

• Journal of Forest and Environmental Science
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• v.33 no.2
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• pp.97-104
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• 2017

Investigation was carried out on response of Tetrapleura tetraptera (Schum. and Thonn.) to soil, water and light with the view of its domestication and introduction to different ecological regions. The experiment was arranged in a factorial experiment of $3{\times}3{\times}3$ in a completely randomized design (CRD) with three replicates. The factors were: soil textural class (Loamy sand, Sand and Sandy clay loam), watering regime (daily, twice a week and once a week) and light intensity (100%, 75% and 50%). Soil textural classes had significant influence on collar diameter, stem height, number of leaflets, root/shoot ratio and relative growth rate of Tetrapleura seedlings. Seedlings grown on loamy sand recorded the highest mean value- 2.28 mm for collar diameter, stem height- 12.9 cm, number of leaflets- 19.9, chlorophyll b- $0.34mg\;mL^{-1}$, leaf relative water content- 27.4% and relative growth rate- $0.037mg\;g^{-1}\;day^{-1}$. Watering regime had significant influence on the collar diameter of Tetrapleura. Seedlings watered daily recorded the highest mean value- 2.25 mm for collar diameter. Light intensity significantly influenced collar diameter and root/shoot ratio. Seedlings exposed to 100% light intensity recorded higher mean value for collar diameter- 2.28 mm and root/shoot ratio- 1.481 cm. The interaction between soil textural class and light intensity significantly affected collar diameter, stem height and number of leaflets. Higher mean value for collar diameter (2.47 mm) stem height (13.25 cm) and number of leaflets (21.16) were recorded while the interaction between soil textural class, light intensity and watering regime was significant for only number of leaflets. Tetrapleura exhibited some level of tolerance to different soil texture, drought and light intensity. Therefore, Tetrapleura has the potentials to be raised in different ecological zones characterized by difference in soil, rainfall and amount of sunshine.

• Korean Journal of Environmental Agriculture
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• v.37 no.2
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• pp.87-96
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• 2018

BACKGROUND: The vigorous shoot growth in upper part of apple tree canopy leads to poor fruit quality and flower bud formation in lower part of canopy. So, this study was conducted to develop the proper control method about the shoot growth in upper part of apple tree canopy. METHODS AND RESULTS: Trunks of 'Fuji'/M9 apple trees were cut (back pruned) to 2.5 m in tree height on 11 February (dormant) or 12 April (full bloom). Naphthalene acetic acid (NAA) was applied at 2.0% to cut surface when trunk was pruned. Prohexadione-calcium (Pro-Ca) was sprayed at 250 mg/L above 2.0 m in tree height at 23 April (petal fall). The NAA or Pro-Ca application after trunk was pruned at dormant (TR-2 and TR-3) significantly reduced shoot growth in upper part of canopy compared with the control (tree was only pruned at dormant, TR-1), but the percent of shoots showing the secondary growth of TR-3 was higher over 2 times than that of TR-2. The reduction of shoot growth in upper part of canopy by TR-2 and TR-3 increased the fruit red color from the lower part in the treating year and blooming of the lower part in the following year. CONCLUSION: Applying 2.0% NAA to cut surface of pruned apple trunk at dormant was the most effective way for stabilization of the tree vigor in upper part of the canopy in a high density apple orchard.

• International Journal of Industrial Entomology and Biomaterials
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• v.4 no.2
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• pp.143-147
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• 2002

Studies on the interrelationship between biological yield and harvest index, and their association with shoot rearing were carried out in 9 promising mulberry genotypes, which indicated significant variations among genotypes. Biological yield had close association with leaf yield components indicating that they are inter-related for higher productivity in mulberry, Biological yield revealed highly significant positive correlation with important leaf yield components. However height of the longest branch showed negative correlation with biological yield. Genotypes with higher biological yield associated with low ratio of stem weight to leaf weight and high Harvest index on dry weight basis are to be selected for shoot rearing. Biological yield recorded on fresh weight basis had less impact on the present study in comparison to dry weight basis.