• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.3
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• pp.243-250
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• 2004

Two cultivars which are glutinous (Hawcheongchalbyeo) and non-glutinous (Hawcheongbyeo) near isogenic line of rice, were used for this study. The objective of this experiment was to gain the basic information for increasing grain yield of waxy rice by means of source and sink size control. In both Hwacheongbyeo and Hawcheongchalbyeo, the trend of decrease in total and average spikelet weight was ranked as follows; removal of penultimate leaf＜ removal of flag leaf＜ removal of flag leaf and 3ya leaf from the top ＜ removal of flag leaf and penultimate leaf ＜ removal of flag leaf, penultimate leaf, and 3rd leaf from the top. The reduction yale of total and average spikelet weight per panicle of Hwacheongbyeo was higher than those of Hwacheongchalbyeo according to the removal of flag leaf, penultimate leaf, and 3rd leaf from the top. In both cultivars, high-density grain ratio and grain filling ratio of the primary branches were higher Hun those of the secondary branches by leaf clipping treatment. The spikelet number and total spikelet weight per pinicle in both Hwacheongbyeo and Hwacheongchalbyeo were decreased by removal of spikelets on branches compared with control, whereas average spikelet weight and grain filling ratio were increased. The increase rate of average spikelet weight of Hwacheongchalbyeo was much higher than that of Hwacheongbyeo by sink size control. High-density grain ratio by removal of spikelets on branches was higher in Hwacheongchalbyeo, but filled grain ratio was higher in Hwacheongbyeo.

• Weed & Turfgrass Science
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• v.7 no.3
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• pp.259-268
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• 2018

This study was conducted to evaluate the effect of liquid fertilizer containing humic acid and Saccharomyces cerevisiae broth (LHS) on changes of turfgrass growth by investigating visual quality, chlorophyll content, dry weight of clipping, and nutrient content in leaf tissues. Treatments were designed as follows; control fertilizer (CF), HS-1 ($CF+1.0mL\;m^{-2}\;LHS$), HS-2 ($CF+2.0mL\;m^{-2}\;LHS$), and HS-3 ($CF+4.0mL\;m^{-2}\;LHS$). After treatment of LHS on creeping bentgrass, soil pH in the treated plots was decreased than that of CF. As compared to CF, visual quality, chlorophyll content and content of N, P and K were not significantly different in the LHS treatments. However, clipping yield and phosphorus uptake of HS-2 were significantly increased by 22% and 33%, respectively. These results showed that application of LHS improved the phosphorus uptake and growth of creeping bentgrass, which would be an alternative management tool for the cool season turfgrass under stress conditions.

• Asian Journal of Turfgrass Science
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• v.23 no.2
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• pp.353-360
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• 2009

Phosphorus (P) is one of the essential elements of the phospholipids that are involved in the formation of plant cell membranes. Phosphorus is highly immobile in soils and is often a limiting nutrient for plant growth. Phosphorus mobility and availability varies with several factors such as application frequency, placement in the soil, and the amount of irrigation or precipitation. This study was conducted to evaluate the effect of P applications at level of 0, 146, and 293 $kg{\cdot}ha^{-1}$ at four mixing depths (0, 7.6, 15.2, and 22.9 cm )on the growth and establishment of Kentucky bluegrass (Poapratensis L.) in a sand-based system.Grass clipping samples were collectedevery two weeks, dried, and weighed. Total root dry weight, root organic matter, and tissue content of P were measured at the end of the study. Leachate was collected weekly and analyzed for total P concentration. No difference was found between application of P to the surface and to the 7.6 cm mixing depth. However, surface application with 146 and 293 kg $P{\cdot}ha^{-1}$ produced 8-10% and 16-20% more P in tissue than subsurface applications, respectively.

• Korean Journal of Environmental Agriculture
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• v.42 no.4
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• pp.286-296
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• 2023

This study was conducted to evaluate the effects of soil microbial fertilizer (SMF) containing Saccharomyces cerevisiae HS-1 and Streptococcus thermophiles HS-2 on the growth of creeping bentgrass. For the pot experiment, the treatments were as follows: no fertilizer (NF), control (3 N g/m²/month), SMF-1 (control+SMF 2 mL/m²/time), and SMF-2 (control+SMF 4 mL/m²/time). For the plot experiment, the treatments were as follows: NF, control, SMFp-1 (control+SMF 1 mL/m²/time), SMFp-2 (control+SMF 2 mL/m²/time), and SMFp-3 (control+SMF 4 mL/m²/time). In the pot experiment, visual turfgrass quality and the uptake amount of nitrogen (N) and potassium (K) were increased under the SMF treatments, whereas the content of chlorophyll (a, b, and a+b) and clipping yield were not considerably different compared with the control. In the pot experiment, the amount of SMF positively correlated with visual turfgrass quality and uptake amount of N and K. In the plot experiment, turfgrass density was increased by 12.9-19.2% under SMFp treatments compared with the control. These results indicated that the application of SMF containing Sa. cerevisiae HS-1 and St. thermophiles HS-2 improved the quality, density, and growth of creeping bentgrass via prompting the uptake of N and K.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.2
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• pp.137-152
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• 2009

Present experiment was conducted at the field of Gyeongnam Agricultural Research and Extension Services in Jinju city for two continuous cropping seasons to develop several adaptable and valuable year-round forage-producing system for elevating self-sufficiency and dollar-saving by reduced importing of crude forage. Twenty cropping systems were tested in experiment using whole crop barley (WCB), oat, rye, Italian ryegrass (IRG), and triticale in winter season and com, sorghum, sorghum ${\times}$ sudangrass hybrid, and oat in summer time. Sorghum ${\times}$ sudangrass hybrid showed highest fresh forage yield among experimented summer season crops, and followed com. Com produced the most dry matter yield, and followed sorghum${\times}$sudangrass hybrid, sorghum and oat in order. There was no significant effect of former winter crops on fresh and dry matter production succeeding summer time crops. Among winter season forage crops tested, oat showed the highest fresh and dry matter when clipped on mid-May, and followed triticale, IRG, rye and WCB. Winter-time cultivated crops showed no clear effect on the growth and forage (fresh and dry matter) producing ability of following summer crops. There was the most protein content in oat plant among summer season planted crops, and in sorghum for acid detergent fiber (ADF) and in sorghum ${\times}$ sudangrass hybrid for neutral detergent fiber (NDF), respectively. While, com showed highest value of relative feed value (RFV) and total digestive nutrients (TDN) among those crops. Among winter crops, the highest crude protein was in oat plant showing no significant differences of ADF and NDF, while, relatively higher value of RFV was recognized with rye and triticale. Also, triticale contained more TDN as compare to other forage crops. The cropping combinations such as com followed by (fb) rye and maize fb triticale were regarded as promising systems having higher dry matter producing ability among tested combinations. Considering TDN producing potential, the combinations with sorghum ${\times}$ sudangrass hybrid fb triticale andlor rye were would be suitable ones, coincidently. There was a tendency which elevating pH, electric conductivity (EC) and organic matter (OM) contents in soil after experiment comparing to before planting. More crude protein content in plant was shown at mid-May clipping as compared to the forage at April cut in all winter season grown crops. ADF and NDF contents were increased by delayed clipping showing decreased tendency of RFV and TDN in plant. In conclusion, many cropping systems would be available using above mentioned forage crops according to farmer's conditions and scale, etc.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.4
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• pp.383-388
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• 2011

This study was carried out to determine the effect of seeding dates of Italian ryegrass interseeded into bermudagrass sod on the forage productivity and botanical composition of Italian ryegrass and bermudagrass. Experimental plot was located at 200 m altitude within Subtropical Animal Experiment Station, National Institute of Animal Science in Jeju from 2009 to 2010. Seeding date treatments of Italian ryegrass into bermudagrass sod were arranged in a randomized complete block design replicated three times. Italian ryegrass was drilled in row 20 cm apart after clipping the bermudagrass at a cutting height of 2~3 cm. Seeding time was on 15 September, 30 September and 15 October. The dry matter yield of Italian ryegrass was higher in 15 September seeding treatment, the dry matter yields of 30 September and 15 October seeding treatment were not different. The Italian ryegrass interseeded into bermudagrass sod didn't affect the dry matter yield in the summer harvests of bermudagrass, and the dry matter yield of bermudagrass showed the highest in August. In botanical composition, Italian ryegrass showed to reduced growth in early seedling stage after seeding by competition with bermudagrass, but Italian ryegrass was dominant to June increasing of temperature in spring next year and bermudagrass after Italian ryegrass harvests was dominant during summer season.

• Asian Journal of Turfgrass Science
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• v.24 no.1
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• pp.45-49
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• 2010

Research on nitrate-nitrogen ($NO_3-N$) leaching in turfgrass indicates that in most cases leaching poses minimal risk to the environment. Although there have been many studies investigating $NO_3-N$ leaching, there has been little research to investigate the effect of compaction level and rootzone mix on nitrogen (N) leaching. The research objective is to determine the effect of compaction level and rootzone mix on nitrogen leaching. The four rootzone mixes are 76.0:24.0, 80.8:19.2, 87.0:13.0 and 93.7:6.3 % (sand:soil). The four levels of compaction energies are 1.6, 3.0, 6.1, and 9.1 J $cm^{-2}$. Nitrogen was applied using urea at a rate of 147 kg $ha^{-1}$ split among three applications. Rootzone was packed into a polyvinylchloride pipe with a perforated bottom to facilitate drainage. Rootzone depth was 30 cm over a 5 cm gravel layer. Each column was sodded with Poa pratensis L. Hoagland solution designed for coolseason grasses, minus N, was used to ensure adequate nutrition in the rootzone. Turf grass quality and clipping yield were recorded from each tube at two-week intervals. The clippings were oven-dried at a temperature of $67^{\circ}C$ for 24 h and weighed. At the end of the study, root dry weight was determined by washing and oven-drying samples at $67^{\circ}C$ for 24 h. Leachate solution was collected weekly for analysis. More than 6.1 J $cm^{-2}$ of compaction energy increased possibilities of surface runoff. The compaction energy between 3.0 and 6.1 J $cm^{-2}$ produced more clipping dry weight and less N leaching than 9.1 J $cm^{-2}$.

• Asian Journal of Turfgrass Science
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• v.3 no.1
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• pp.39-52
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• 1989

Native Kerean lawngrass (Zeysia japonica steud.) and Manilagrass ( Zeysia matrella Merr.) are frequently used as sport turf and lawn in Kerea and ether Asian countries because of its excellent summer qualities and superior winter-hardiness compared to ether warm-season turfgrass . The objective of this study was to investigate the effect of the plant growth retardants ( PGR ) en the inhibition (d the growth of the two Kerean native turfgrasses. Kerean lawngrass and Manilagrass were treated with [2 RS , 3 RS] -1- [4- chlorophenyl ] -4, 4-dimethyl -2- [1 H -1, 2, 4- tiazol -1- y] pentan -3- ol ( PP -333) at 93 and 930 gha -j ; 5-[4- chlorphenyl ]-3, 4, 5, 9, 10- peiitaaza - tetracyclo [5, 4, 1, 0 2 6 . o ~'~I -3, 9- diene ( BAS -106) at 16 and 160 gha ; [ E I-] - cyclohexyl -4, 4- dimethyl -2- [1, 2, 4- triazol -1- yl ]-1-pentene - 3- ol ( NTN -821) at 56 and 560 gha ', and 4- chloro -2- [$\alpha$- hydrozybenzy I isonicotin anilide ( CGR -811) at 92 gha in pot study . All PGR treatments were effective in reducing the plant height, with the exception of BAS -106 at 16 gha for Korean lawngrass ; however , all increased quality to some degree , with the exception of PP -333 at 93 gha . The low PGR rates significantly increased Korean lawngrass height during late jtily aitd mid-August . On the other hand , BAS -106 significantly increased Manilagrass height {rom 24 Septeml)er onwards . All PGR treatments haol higher turfgrass quality than untreatments , and also the high rates of PGIt treatments were more effective in increasing quality than the low rates observed on 8 October . Meanwhile , Manilagrass quality was increased to some extent than Korean lawegrass . PP - 333 was significantly effective in reducing clipping yield and the same results were found with the application of NTN -821 at 560 gha -l for both Korean lawngrass and Manilagrass , BAS -106 at 160 gha for Korean lawegrass , and CGR -811 at 92 gha for Manilagrass . The high PGR rates had higher turfgrass shoot weight observed on 8 October than the low rates , and there were little increases obtained with the low rates of PP -333 for Korean lawngrass and BAS - 1 06 for Manilagrass . Effeets on stolon growth varied between growth retardants , and between retardant treatments ; the high rates of PGR as well as the low rate of NTN -821 elongated stolon of Korean lawngrass and manoilagrass . However , PP -333 at 93 gha and BAS -106 at 16 gha - shortened stolons of Korean lawugrass , resulting in inhibition or little difference of stolon dry weight . NTN -821 at 560 gha and CGR -811 had no positive effect on the stolon length of Manilagrass . 101) -333 and the low rate of BAS -106 and NTN -821 decreased root weight of Korean lawng - rass All PGR rates had negative effect on the root weight of Manilagrass with the exception of BAS -106 CR -811 and the high rate of NTN -821 which made no difference in root weight between retarolant treatments and the control .

• Weed & Turfgrass Science
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• v.4 no.3
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• pp.249-255
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• 2015

Trichoderma spp. were famous fungi used for turfgrass management in golf course. This study was conducted to evaluate effects of two microbial fertilizers containing Trichoderma harzianum and T. atroviride on the growth and quality of creeping bentgrass with turf color index, chlorophyll index, root length, shoot number, clipping yield and nutrient content. Treatments were designed as follow; non-fertilizer (NF), control fertilizer (CF), T. harzianum (TH), and T. atroviride (TA). Chlorophyll index and root length of TH and TA were increased than these of CF and shoot number and content and uptake of nitrogen (N) of TA higher than these of CF. The N content in turfgrass tissue was significantly related to shoot number, root length and N uptake (P<0.05) and shoot number was positively relate to chlorophyll index (P<0.05). These results indicated that application of Trichoderma harzianum and T. atroviride improved a growth and quality of creeping bentgrass by promoting N uptake.

• Weed & Turfgrass Science
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• v.6 no.3
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• pp.262-271
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• 2017

This study was conducted to evaluate incorporation ratio of soil amendment 'Profile' to improve soil physicochemical properties and turfgrass growth. The soil amendment was added 0 (sand only), 3, 5, 7, and 10% to USGA Green-spec green sand soil. As incorporated with more 'Profile' amendment, soil electrical conductivity (EC), cation exchangeable capacity (CEC), capillary porosity and total porosity of root zone were increased than those of control, while bulk density and hydraulic conductivity decreased. Turfgrass index and clipping yield of creeping bentgrass grown in sand soil incorporated with 7% 'Profile' were improved than those of control. Correlation coefficient of turf color index and incorporation ratio of the soil amendment 'Profile' was found to show significantly positive correlation. These results indicated that application of the soil amendment 'Profile' to sand soil in golf course green improved turfgrass growth and quality by increasing CEC and porosity of root zone.