금잔디에 잡초성 버뮤다그래스 방제

태현숙,김용선,허영두 한국잔디학회 2013 Weed & Turfgrass Science Vol.2 No.4

Bermudagrass (Cynodon dactylon.) is one of the most difficult weedy species to control in turfgrass because it’s high tolerant to various environmental and management stresses. This experiment was performed to find the integrated weed management including cultural practices to suppress bermudagrass in Zoysiagrass matrella (L) Merr. As results, two sequential applications of Fluazifop-P-butyl 0.05 ml m-2+ Triclopyr-TEA 0.5 ml m-2 and Fenoxaprop-P-ethyl 0.1 ml m-2 + Triclopyr-TEA 0.5 ml m-2 applied on 20 days intervals were evaluated the primary option for bermudagrass suppression and turfgrass injury was acceptable in zoysiagrass. In both treatments, turf injury was observed during 30days after the first application and almost recovered at 40days. While Fenoxaprop-P-ethyl 0.1 ml m-2 + Triclopyr-TEA 0.5 ml m-22 were lightly phytotoxic to zoysiagrass in chlorophyll content test, there was no growth inhibition of zoysiagrass. Verticut practice (4 mm depth) just before herbicides application where zoyisagrass is contaminated with bermudagrass was not helpful to reduce turf injury in this experiment. However, alone verticut management was utilized to decrease about 12-14% bermudagrass population. Thus the application of Fenoxaprop-P-ethyl 0.1 ml m-2 + Triclopyr-TEA 0.5 ml m-2 which are permitted for turfgrass after zoysiagrass is perfectly recovered from turf injury by verticut practice should be utilized for bermudagrass reduction in zoysiagrass. 버뮤다그래스는 다양한 환경과 관리작업에 대한 내성이높기 초종으로 잔디밭에 침입할 경우 가장 방제하기 어려운 잡초성 초종 중 하나로 분류된다. 본 연구는 금잔디에발생된 버뮤다그래스을 제거하기 위해 관리 방법의 개선이 포함된 종합적인 제초 방법을 찾고자 시행되었다. 연구결과, Fluazifop-P-butyl 0.05 ml m-2+ triclopyr-TEA0.5 ml m-2 및 fenoxaprop-P-ethyl 0.1 ml m-2 + triclopyr-TEA 0.5 ml m-2 을 20일 간격으로 2회 처리한 시험구의버뮤다그래스의 방제 효과가 높았으며 약해 발생도 양호하였다. 두 처리구에서 잔디의 약해는 1차 처리 후부터 약 30일 동안 지속되었으며 40일에는 회복되었다. 이 때 fenoxaprop-P-ethyl 0.1 ml m-2 + triclopyr-TEA 0.5 ml m-2 혼용 처리에서 잔디 엽색의 황화가 발생되었으나 심각한 생육 억제 등은 발생되지 않았다. 제초제 살포 1주일 전 실시한 버티컷 작업은 약효를 유의하게 상승시키지 못하였으나 버티컷 작업만 실시할 경우 버뮤다그래스의 밀도를 12-14% 감소시키는 효과가 있었다. 따라서, 버티컷 작업 후 한국잔디가 회복된 이후 잔디에 고시된 약제인 fenoxaprop-P-ethyl 0.1 ml m-2 + triclopyr-TEA 0.5 ml m-2을 처리하는 것은 한국잔디 약해를 최소화하면서 버뮤다그래스를 서서히 줄여나가 데 효과적인 전략이 될 것이다.

하절기 크리핑 벤트그래스의 품종별 특성비교

태현숙,이형석,안길만,김종보,Tae, Hyun-Sook,Lee, Hyung-Seok,An, Kil-Man,Kim, Jong-Bo 한국잔디학회 2006 한국잔디학회지 Vol.20 No.2

본 연구는 하절기 크리핑 벤트그래스의 품종별 생육특성을 파악하고자 수행하였다. 하절기에 품질이 가장 나빴던 품종은 Penncross 였으며 가장 좋았던 품종은 Pen A-4와 Crenshaw 였다. Putter의 경우 하절기에도 품질의 변화가 크지 않아 조사기간 내내 고른 품질을 유지한 품종으로 평가되었다. 하절기에도 엽록소 함량이 우수한 품종은 Crenshaw, L-93과 Pem A-4였으며, 가장 낮았던 품종은 Penncross이고 SR1020도 상당히 낮은 그룹에 속하였다. 시비 후 엽록소 함량이 가장 많이 증가하는 품종은 Putter였다. 최고온기인 8월 초에 $1cm^2$ 단위면적당 밀도가 가장 높은 품종은 L-93으로 19.3개이었고 그 다음은 Crenshaw, Pen A-4, Putter, Dominant, SR1020, Penncross 순으로 나타났다. 가장 낮았던 Penncross의 밀도는 15.7 개였다. 뿌리생육이 가장 좋았던 품종은 L-93으로 하절기에도 평균 5.5cm이상을 유지하는 것으로 나타났으며 Pen A-4와 Putter의 뿌리생육도 양호한 것으로 나타났다. 하지만 SR1020, Penncross, Dominant품종은 하절기에 뿌리생육이 급격히 감소하였다. 실험 기간 동안 가장 문제가 되었던 잔디병은 브라운 패취였으며 Penncross를 제외한 모든 품종에서 Brown patch가 발생되었다. Dominant가 가장 많았고 Putter, L-93, Crenshaw, SR1020, Penn A-4 순으로 나타났다. 하절기조류 피해가 가장 적은 품종은 Penn A-4였으며, Dominant가 가장 심한 것으로 나타났다. 본 실험을 통해, 하절기 생육이 가장 우수하였던 품종은 Crenshaw, Penn A-4, L-93 이었으며 가장 불량하였던 품종은 Penncross 였다. 하지만, 이는 조성 1년차 그린에서 나타난 결과이므로, 앞으로 시간이 경과함에 따라 나타나는 다양한 품종의 특성에 대한 종합적인 연구가 이루어져야 할 것으로 사료되었다. This study was initiated to evaluate the growth characteristics of seven creeping bentgrass cultivars in summer, 'Penncross' showed the worst visual quality, whereas 'Penn A-4' and 'Crenshaw' the best quality. 'Putter', which was maintained a fair quality during the test period, was regarded as a good cultivar because of no significant variation in summer as compared to the other caltivars. 'Crenshaw',' L-93' and 'Penn A-4' were greater in chlorophyll content and 'Penncross' lowest during the summer. Also, 'SR1020' had a low content of chlorophyll. 'Putter' greatly increased in chlorophyll content after fertilization. The highest shoot density($19.3/cm^2$) was found with 'L-93' in early August, followed by 'Crenshaw', 'Penn A-4', 'Putter', 'Dominant', and 'SR1020' in that order. However, 'Penncross' was lowest($15.7/cm^2$). As for a root length, 'L-93' was longest, being over an average 5.5cm. 'Penn A-4' and 'Putter' also showed good result in root growth. However, the root length considerably decreased with 'SR1020', 'Penncross' and 'Dominant' in summer. Brown patch was a serious disease for the most cultivars, except 'Penncross'. 'Dominant' had the most serious damage. 'Putter', 'L-93', 'Crenshaw', 'SR1020', and 'Penn A-4' were also greater in damage over the others. In regards of algae occurrence in summer, 'Penn A-4' had the least damage, while 'Dominant' the greatest. In conclusion, 'Crenshaw', 'Penn A-4' and 'L-93' were the best cultivars in terms of summer growth. Conversely, 'Penncross' was the poorest one. However, this study was conducted under the conditions of one-year old green. Accordingly, in-depth experiment should be done over several years to elucidate the characteristics of growth for the wide range of creeping bentgrass cultivars during the summer.

켄터키 블루그래스 페어웨이에서 문제가 되는 크리핑 벤트그래스 방제

태현숙,Tae Hyun-Sook 한국잔디학회 2005 한국잔디학회지 Vol.19 No.2

페어웨이나 티가 켄터키 블루그래스로 조성된 골프장에서 최근 큰 문제가 되는 부분이 바로 크리핑 벤트그래스의 침입으로 이것은 골프장 전체의 미관을 크게 떨어뜨리지만, 번식속도가 빨라 매년 피해면적이 늘어나는 추세이다. 본 연구에서는 크리핑 벤트그래스 발생 초기에 약제를 처리하여 켄터키 블루그래스 약해를 최소화 하면서 크리핑 벤트그래스만 효과적으로 제거 할 수 있는 방법을 찾고자 한다. 다양한 약제실험을 수행한 결과, 크리핑 벤트그래스 방제 효과가 높을수록 켄터키 블루그래스에 약해가 심하게 나타나는 경항을 보였으나, fenoxaprop + triclopyr 처리에서는 크리핑 벤트그래스 방제가가 $80\%$ 이상 되었으며, 켄터키 블루그래스 생육에 미치는 영향도 적은 것으로 조사되었다. 반면, 크리핑 벤트그래스의 생육은 다시 회복되지 못하였는데 이는 fenoxaprop이 다습하고 낯은 기온에서 약효가 높아져 제초제 민감성이 매우 높은 크리핑 벤트 그래스가 약해 스트레스를 극복하지 못하는 특성과 관계가 있는 것으로 추측되었다. 따라서, 골프장의 켄터키 블루그래스 티나 페어웨이에 발생된 크리핑 벤트그래스에 fenoxaprop + triclopyr를 부분 처리하여 크리핑 벤트그래스 발생을 크게 억제할 수 있을 것으로 기대되며, 다만 다년생 잡초를 1$\sim$2회 시약으로 완전히 방제하기는 어려우므로 연차적으로 발생면적을 줄여나간다는 개념이 필요하다. 향후 추가 약제선발 뿐 아니라 적정방제시기에 대한 종합적인 연구가 진행된다면 국내의 골프장 관리자들에게 많은 도움이 될 것으로 기대된다. 함량에는 미치지 못했다. 총콜레스테롤에 대한 콜레스테릴 에스테르의 비율은 고콜레스테롤혈증 유발식이 급여로 정상군에 비하여 $13\%$이상 증가됐으나 질경이 에틸아세테이트 분획 병합투여로 대조군에 비하여 $1-7.5\%$가 감소되었다. 6. LDL-콜레스테롤 함량은 고콜레스테롤혈증 유발 식이급여로 정상군보다 $90\%$이상 증가됐으나 질경이 에틸아세테이트분획 병합투여로 유의하게 감소되었고, HDL-콜레스테롤 함량은 콜레스테롤혈증 유발 식이 급여로 정상군에 비하여 $34.1\%$가 감소됐으나 질경이 에틸아세테이트분획 병합투여로 감소된 HDL-콜레스테롤 함량이 유의하게 증가되었다. 고콜레스테롤혈증 유발식이 급여로 $524\%$가 증가된 동맥경화지수는 질경이 에틸아세테이트 분획 병합투여로 대조군에 비하여 $40.2\%,\;51.2\%$가 감소됨으로써 동맥경화 발병 위험율이 대조군에 비하여 감소되었다. HDL-콜레스테롤 함량/총콜레스테롤 함량 비는 고콜레스테롤혈증 유발 식이 급여로 정상군보다 $73.9\%$가 감소됐으나 질경이 에틸아세테이트 분획 병합투여로 대조군에 비하여 유의한 증가를 나타냈다. 26두가 발정 반응($96.3\%$)을 나타내어 2.75${\~}$3.5의 경우가 2.50 이하의 경우에 비하여 높은 발정반응을 나타내었다.osterone과 0.40의 정의 상관이었고 근내지방도와 creatinine 농도간에는 -0.55의 비교적 높은 음의 상관계수가 Creeping bentgrass (Agrostis palustris Huds.) had been the problematic weed for Kentucky bluegrass (Poa pratensis L.) fairway since it shows light green color all year. Experiment was carried out to determine the best herbicides combination to control creeping bentgrass in Kentucky bluegrass. fairway without injury. To investigate the efficacy of herbicides, five post-emergence herbicides of asulam WG ($87.6\%$), imazaquin SL ($20\%$), fenoxaprop-P-ethyl EC ($7\%$), mecoprop SL ($50\%$), triclopyr-TEA SL ($30\%$) and one pre-emergence herbicide pendimethalin EC ($31.7\%$) treated on 21 Sept. and 10 Nov. 2003. Kentucky bluegrass visual quality evaluated 30 and 50 days after application for phytotoxic effects of the herbicides. As a result, asulam WG (0.2g/$m^{2}$) and imazaquin SL (0.3ml/$m^{2}$) showed approximately $90\%$ of control in creeping bentgrass, but visual quality of Kentucky bluegrass significantly decreased from 20 to 50DAT (day after treatment). However, creeping bentgrass was acceptably controlled(over $80\%$) by fenoxaprop-P-ethyl EC (0.4ml/$m^{2}$)+triclopyr-TEA SL(0.3 ml/$m^{2}$) applied twice on 21 Sept. and 1 Oct. 2003 without serious injury on Kentucky bluegrass. Therefore, it is suggested that an application of fenoxaprop-P-ethyl EC (0.4ml/ $m^{2}$)+triclopyr-TEA SL (0.3 ml/$m^{2}$) may be more effective to control creeping bentgrass in Kentucky bluegrass with the least phytotoxicity by herbicides.

생장조절제 처리가 bentgrass 생육과 토양 수분이동에 미치는 영향 ( Effect of Trinexapac-ethyl on the growth and changes of soil water content in bentgrass green )

태현숙,고석구,안길만 한국잡초학회·한국잔디학회 2000 Weed & Turfgrass Science Vol.14 No.1

생장조절제 처리가 bentgrass 생육과 토양 수분이동에 미치는 영향

태현숙,고석구,안길만 한국잔디학회 2000 한국잔디학회지 Vol.14 No.1

This study was conducted to evaluate an efficiency of plant growth regulator trinexapacethy(Primo) on the growth response of bentgrass and the change to soil water content in bentgrass green. Based on the results of the study, the following results were observed. 1. During four weeks after treatment, the visual color and turfgrass density of all the treated plots with trinexapac-ethyl(Primo) were more improved rather than without. Two treatments trinexapac-ethyl /$0.02mL\m^2$ and $0.04mL/\m^2$ were more favorable than other treatments. 2. It suggested that optimum rate to reduce the bentgrass growth and to increase the turfgrass density was the trinexapac-ethyl $0.04mL/\m^2$. 3. For six weeks after treatment, all treated plots were not significantly different (P<0.05) in turfgrass root length and root dry weitht. 4. In the treated plots with trinexapac-ethyl $0.04mL/\m^2$ for 25days in bentgrass green, soil water consumption was approximately 35% to 40% compare to the non-treated control.

골프장 답압지역의 토양개량

태현숙,김용선,고석구 한국조경학회 2000 韓國造景學會誌 Vol.27 No.5

The purpose of this study is to investigate the effects of soil amendments for reducing soil compaction at heavy traffic area in golf course. Major results of this research are summarized at follows: 1. In the Lab. experiment, the porosity was improved significantly when the materials, such as peatmoss, charcoal, and tire chip mixtures were used respectively. Especially mixture of sand and 20% peatmoss showed higher effectiveness (10%) in porosity, comparing with ordinary sand. This soil mixture(sand 80%+peatmoss 20%) was observed the best in water retention, soil hardness and hydrauric conductivity. 2. In the greenhouse experiment, traffic pressure was given 7 times a day on several combination of mixture treatments to see the top dry weight. The soil mixture of 20% peatmoss showed the highest in the top dry weight. When the more traffic pressure(15 time/day) were given on the different treatment, the top dry weight was significantly reduced. However, the mixture of 20% peatmoss also had the least influence on this type of heavy traffic. 3. In the field experiment, the soil amendments were treated in traffic area f golf course, and observed at 30days, 60days, 90days, 120days after treatment. Visual turf quality(color), root length and soil compaction were compared to those of control. As a result, overall treatments with soil amendments were effective, which showed better turf quality and less soil compaction. 4. In the field test, physical characters of soil (such as soil hardness and hydrauric conductivity) in sand+tire chip+peatmoss(60:20:20, %, v/v) treatment was significantly improved. Also in the slow increasing of traffic, the soil compaction was the most effective in reducing soil hardness.

한국잔디 신품종 ‘그린에버’의 개발 및 특성

태현숙,홍범석,신종창,장공만,김경덕,박대섭 한국잔디학회 2014 Weed & Turfgrass Science Vol.3 No.4

This study was performed to study characteristics of new zoysiagarass cultivar ‘Green Ever’ (Plant Variety ProtectionApplication no. 2014 - 02). ‘Green Ever’ was developed by selection breeding among 100 native zoysiagrasses collected inSouth Korea. ‘Green Ever’ showed specific bands (1.48 kb with OPC14 and 1.05 kb with OPD5) which were distinct from ‘AnyangJoonggi’ or ‘Dongrae Koryogi’ in RAPD analysis. ‘Green Ever’ was classified as Z. matrella in morphological evaluations includingplant height (6.8±0.5 cm), leaf width (2.0±0.1 mm), height of lowest leaf (1.9±0.1 cm) and seed length (3.0±0.1 mm), which wassimilar with morphological characteristics of ‘Dongrae Koryogi’. Turf quality, shoot density and chlorophyll content of ‘Green Ever’were higher than them of ‘Anyang Joonggi’ and ‘Dongrae Koryogi’ under intensive management such as fairway on golf course,especially shoot densities of ‘Green Ever’ were excellent higher than ‘Anyang Joonggi’ and ‘Dongrae Koryogi’ during experimentalperiods. It could be extensively used in fairway, teeing ground of golf courses and landscape garden after further study about variousenvironmental adaptabilities such as winter kill, wear tolerance etc.. 본 연구는 한국잔디 신품종 ‘그린에버’(품종보호출원2014-02)의 특성을 연구하기 위해 수행되었다. ‘그린에버'는한국에서 수집한 100개의 자생 한국잔디에서 선발 육종된품종이며 유전자 분석을 통해 ‘안양중지’, ‘동래고려지'와품종의 차별성을 확인하였다(1.48 kb with OPC14 and 1.05 kbwith OPD5). ‘그린에버'의 형태적 특성 평가결과 잔디의 초장(6.8±0.5 cm), 엽폭(2.0±0.1mm), 최하위 엽까지의 높이(1.9±0.1 cm) 및 종자의 길이(3.0±0.1 mm) 등은 금잔디의 특성을 띠는 것으로 분류되었으며, 형태적 특성은 ‘동래고려지’와 유사하였다. 골프장 페어웨이 관리 조건에서 ‘그린에버’의 잔디 품질, 밀도, 클로로필 등은 ‘안양중지’ 및 ‘동래고려지’ 보다 뛰어난 것으로 조사되었으며 특히 조사기간동안 그린에버의 밀도는 ‘안양중지’ 및 ‘동래고려지’ 보다탁월하게 높은 수준을 유지하였다. 향후 ‘그린에버’의 내한성, 내마모성 등 다양한 환경적응성이 검증된다면 골프장페어웨이, 티잉그라운드 및 정원 등에 널리 활용될 수 있을 것으로 기대된다.

골프장의 농약 사용방안

태현숙 한국골프학회 2008 골프연구 Vol.2 No.1

Environmental problems on golf course has been argued for a long time in the world. It has been supposed that soil contamination by agriculture chemicals could be more serious by increasing of golf courses. However, we are confusing since there is little information or studying about environmental effects of golf courses in Korea. Therefore, it is very important to understand well the characteristic and the usage of pesticide and herbicide for environmental preservation. There are 3 points in order to reduce the effects of agricultural chemicals. 1) what is the best chemical in each golf course 2) when is the best time to spray chemicals 3) how to decrease the scattering and moving of chemicals. It must be more useful for many golf course managers to protect environment, but there are many management programs including pesticide management in golf courses. In conclusion, it can be proposed to consider not only the agricultural chemical program but also the integrated pest management system for eco -friendly golf courses.

하절기 켄터키블루그래스 관리를 위한 식물생장조절제 Trinexapac-ethyl의 활용

태현숙,홍범석,조용섭,오상훈 한국잔디학회 2010 Weed & Turfgrass Science Vol.24 No.2

This study was performed to provide useful information for kentucky bluegrass management during summer by application of plant growth regulator, Trinexapac-ethyl. Visual quality, shoot density and chlorophyll contents of treatment blocks were significantly different from those of control during summer by application of Trinexapac-ethyl. The turfgrass density of treatment was increased of 4ea/10 cm², especially about 5ea/10 cm² during the growth retarded period of June and July. Chlorophyll contents index and visual quality of kentucky bluegrass were improved by application of Trinexapac-ethyl during summer, too. In addition, the occurrence of foliage in rainy and high temperature season was less than that of control. However, there was no significant difference in the root length of Kentucky Bluegrass. Meanwhiles, mowing height of kentucky Bluegrass was suppressed by 38% at 2 WAT week after treatment and that there was no significant growth of treatment at 4 WAT. In this experiment, turfgrass quality was significantly better than that of control during July, even though trinexapac-ethyl wasn't applied at all in July. Consequently, periodic treatment of trinexapac- ethyl from spring would be very important to promote the turfgrass visual quality during summer which is unfavorable season on the growth of kentucky bluegrass. And it is possible to reduce mowing times at least 30% for 2 weeks by one application of Trinexapac-ethyl 0.02~0.03 ml/m² in kentucky bluegrass fairway. Additively, trinexapac- ethyl treatment can be helpful environmentally by cutting down the fertilizers and pesticides in golf course.

하절기 켄터키블루그래스 관리를 위한 식물생장조절제 Trinexapac-ethyl의 활용

태현숙,홍범석,조용섭,오상훈,Tae, Hyun-Sook,Hong, Beom-Seok,Cho, Yong-Sup,Oh, Sang-Hun 한국잔디학회 2010 한국잔디학회지 Vol.24 No.2

본 연구는 식물생장조절제 trinexapac-ethyl을 켄터키블루그래스에 처리한 후 잔디의 생육특성을 조사하여, 하절기 잔디 관리 정보를 제공하고자 수행되었다. Trinexapacethyl의 처리 후 잔디의 시각적 품질, 잔디밀도, 클로로필 함량이 높아졌고, 특히 켄터키블루그래스 생육이 불량한 하절기에는 유의적인 차이를 보였다. 잔디 밀도는 대조구에 비해 평균 4개($10\;cm^2$) 높았으며, 6~7월에는 5개 이상 높았다. 클로로필 함량과 시각적 품질에서도 봄, 가을 보다는 하절기에 대조구보다 높은 품질을 유지하며, 특히 장마철과 고온기에는 하엽이 적게 발생되어, trinexapac-ethyl에 의한 하고 스트레스 경감 효과가 있을 것으로 생각되었다. 하지만, 식물생장조절제 처리 후에도 뿌리 길이의 신장에는 큰 차이가 없었다. 한편, trinexapac-ethyl 0.025 ml/$m^2$ 처리 후 켄터키 블루그래스의 예고는 처리 2주후 38%까지 억제되다가, 3주부터는 큰 차이를 보이지 않았으며, 식물생장조절제의 효과가 떨어진 4주째에도 잔디가 급격하게 웃자라는 현상은 보이지 않았다. 놀랍게도 생장조정제는 7월에 단 한 차례도 처리되지 않았으나, 7월의 잔디상태는 무처리에 비해 훨씬 안정적으로 유지되었다. 결과적으로, 켄터키 블루그래스 잔디밭에서 여름철 잔디 생육을 높이기 위해서는 봄부터 꾸준히 사용하는 것이 중요하며, 생장조정제를 0.02~0.03 ml/$m^2$의 농도로 살포하면, 약 2주 동안, 예지횟수를 최소 30%는 줄일 수 있을 것으로 예상된다. 부가적으로, 하절기 잔디 품질이 높아지면서 자연스럽게 관리자는 시비나 농약 살포 횟수를 줄일 수 있으므로 환경적으로도 많은 도움이 될 것으로 기대된다. This study was performed to provide useful information for kentucky bluegrass management during summer by application of plant growth regulator, Trinexapac-ethyl. Visual quality, shoot density and chlorophyll contents of treatment blocks were significantly different from those of control during summer by application of Trinexapac-ethyl. The turfgrass density of treatment was increased of 4ea/$10\;cm^2$, especially about 5ea/$10\;cm^2$ during the growth retarded period of June and July. Chlorophyll contents index and visual quality of kentucky bluegrass were improved by application of Trinexapac-ethyl during summer, too. In addition, the occurrence of foliage in rainy and high temperature season was less than that of control. However, there was no significant difference in the root length of Kentucky Bluegrass. Meanwhiles, mowing height of kentucky Bluegrass was suppressed by 38% at 2 WAT week after treatment and that there was no significant growth of treatment at 4 WAT. In this experiment, turfgrass quality was significantly better than that of control during July, even though trinexapac-ethyl wasn't applied at all in July. Consequently, periodic treatment of trinexapac- ethyl from spring would be very important to promote the turfgrass visual quality during summer which is unfavorable season on the growth of kentucky bluegrass. And it is possible to reduce mowing times at least 30% for 2 weeks by one application of Trinexapac-ethyl 0.02~0.03 ml/$m^2$ in kentucky bluegrass fairway. Additively, trinexapac- ethyl treatment can be helpful environmentally by cutting down the fertilizers and pesticides in golf course.