| The study on lawn weeds on eight cities of Guangxi during 2000-2003 years had been carried out. The main results are as follows: there were 34 families, above 136 species weeds, in which 23 species were determined endanger and must control weeds. They were Cynodon dactylon, Digilaria sanguinalis, Eleusine indica,Cyperus rotundus, Kyllinga brevifolia,K. leiolepis, Ageraium conyzoides , Artemisia argyi , Hydrocatyle sibthorpioides, Centella asiatica, Conyza canadensis, Eclipta prostrata, Gnaphalium affine, Phyllanthus urinaria, Alternanthera Philoxeroides , A. sessilist Mazus japonicus , Capsella bursa-pastoris, Oxalis corniculata, O. corymbosa, Solanum nigrum, Euphorbia hirta, Spliva anthemifolia.Their ocurrency frequency ranged 62.3% to 93.4%, and harm index ranged 27.4 to 60.2. Gramineae is the largest specise of weed, it had 29 specise (21.3% of total). Cyperaceae and Compositae is 25,12 specise(18.4%,8.8% of total) respectively.According to ecology region of different cities, mostly weed community was divided out and controlled target was determined.The herbicide test results showed that MCPA, flazasulfuron, bentazone,etc.can selectively control a part of lawn weed, the Lactofen, ethoxysulfuron, anilofos, cyhalofop-butyl and tribenuron were discovered that can selectly control the lawn weeds,and their safety was appraisemented on lawn.According to consist of weed communities,developed a series of selective mixture-herbicide, such as Lu hai yin ,Lu hai ling etc., the effecacy was satisfacty through 3 years test on the lawn. Luhaiyin had a (stem and foliage treatment) control effecacy over 95% against broad-leaf and Cyperaceae weeds, luhailin over 96% against gramineous and part of latifoliate weeds,luhaijing over 90% against annual seed weeds, and it can persist 60d. Ecaoxin had 100% control effecacy against perennial latifoliate and Gramineae weeds.The Cause of lawn weed harm was owed to unnormative planting, unpopularizative professional knowledge of administrantor, unappropriate herbicide in market,fund insufficiency.The study put forward one model viz.research institute together with enterprise would gain effeciency and effecacy.Controling index was less than 6plant/m~2 in ,less than 3plant/m~2 in five-star hotel, restaurant and golf, the height of weed was lower than lawn,and it had no phytotoxicity,safety to environment. Throughout 3 years of technical responsibility mangement,the control effecacy reached 92.3%, in comparsion with manpower that it can save 900 RMB/hm~2 each time.The quality of lawn can enhance from 6 level to 8.2 level,and had no phytotoxcity to trees, flowers and animals.And created satisfactorily social,economic and ecological efficiency. |
