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Importancia de las malezas acuáticas y su control en Puerto Rico Edwin Abreu University of Puerto Rico
Objetives  1.To introduce insects for biological control of aquatic weeds: alligatorweed, waterlettuce and waterhyacinth. 2. To rear and release insects for  the establishment  in Puerto Rico. 3.  Periodic sampling on plant density and insect damage to determine the  impact  of these  insects on aquatic weeds.
Problems produced by aquatic weeds ,[object Object]
2. Disrupt the natural ecology by substitution of  native flora and fauna.
3. Floating mats obstruct navigation and recreation activities.
4. Change water parameters  [CO2], [O2], pH.
5. Exacerbate mosquito problems.
6. Increase water loss by evapotraspiration(3.7 times water loss).  ,[object Object]
Total Phosphorus in lakes in Puerto Rico. Límit EPA  in PR 1,000ug/L  Criteria Std proposed by  Martínez 2003  20ug/L Carr DB Pl CA GA GU CiD Martínez 2002
Water quality criteria for nitrogen Junio 1998 water hyacinth and water lettuce can grow at  5 ppm http://www.epa.gov/waterscience/standards/nutstra3.pdf
12 A D E B F C Propagation of alligatorweed and water lettuce in greenhouse in the Agriculture Experimental Station in Isabela. alligatorweed Water lettuce
Alligatorweed biocontrol agents introduced in Puerto Rico Stem borer flea beetle Vogtia malloi Egg mass
Alligator weedAlternanthera phylloxeroides(Amaranthaceae)
West area in Puerto Rico
Majagual Creek  Feb 27 1999 January 2000
mayo 2006 marzo 2007  Majagual Creek, Mayaguez
Río Hondo River, Bayamón  N 5 3 2 1 4
El AmalJanuary 24 2001
Liberación de A. hygrophila en Viejo cauce Río Hondo, 1 jul.1997. Viejo cauce de Río Hondo área 1, 11 sept. 1997. Viejo cauce de Rio Hondo Bayamón primera area de liberación, 9 de octubre de1997. Viejo Cauce de Río Hondo. Área 1, 9 enero 1998.
Viejo cuace Río Hondo area 3, 19 abril 1999
Río Hondo
Sept 2006 Sept 2006 Feb 2002 Mayo 2005 Río Hondo Bayamón
Río Hondo Area 3, Road 167 Bridge  Area 5, El Amal
Neohydronomus affiniswater lettuce weevil 14 spp. of mosquitos were identified associated with water lettuce. Ej Mansonia, Culex, Anopheles Aedes
Water lettuce Releases of: 2,328 N. affinis weevils .   938 plants   1,804 infested leaves  Campanero, 6 junio  1999
Figura2. Quebrada Campanero en Toa Baja área norte el 3 de octubre de 2000. Figura 1. Quebrada Campanero en Toa Baja,  área norte el  27 enero de 2000. Figura 3. Quebrada Campanero en Toa Baja área norte el 15 noviembre de 2000. Figura 4. Quebrada Campanero en Toa Baja área norte el 10 diciembre de 2000. Figura 5. Quebrada de Campanero en Toa Baja área norte el 1 de febrero de 2001. Figura 6. Quebrada Campanero en Toa Baja área sur el 1 de febrero de 2001.
Campanero, Bo. Ingenio, Toa Baja Campanero 28 ago 2005 Campanero 12 sept 2006
La Plata Dam site December 2000 April 16 1998 January 30 2002
Lago La Plata La Plata, December 12 2005
Eichhornia crassipesJacinto de agua
Lago Carraizo, Trujillo Alto Cuenca hidrográfica
Estado del LagoCarraizo con jacinto de agua en el 2001  Sept 2001
Biocontrol of wartehyacinth in Puerto Rico
Waterhyacinth in Puerto RicoLago Carraizo 6 water sewages treatment plants in the hydrographic captation area sobre 29,564m3 /día
Water surface infested by waterhyacinth in Carraizo Lake   Hortensia 1996   George   1998  Hugo     1989
Sept 2001 March 2004 May 2005 Carraizo, Sector Chomos
Carraizo, Sector Chomos March 2007 May 2007 April 2006
February 2008 March 2009 Carraizo, Sector Chomos
June 2001 June 2001 February 2008
Releases of Neochetina spp weevils and infested plants
Proportion of N. bruchi and N. eichhorniae on water hyacinth in Carraizo Lake.
Number of Neochetina spp. weevils per meter2 in Carraizo Lake.
Orthogalumna terebrantis(Acarina: Oribatida: Galumnidae) Detected in November 2005. Releases begun in Dec 2005. 18 releases : 7,013 leaves of water hyacinth
Releases of the mite O. terebrantis
New aquatic weeds detected in Puerto Rico Giant Salvinia Salvinia molesta
S. molesta at Dorado Golf Pond
Salvinia minima Río Grande Arecibo creek  Caño Tiburones Reserve, Arecibo Also established in  Wild Life Refugee of  Cabo Rojo, DRNA
Cyrtobagous salviniaepicudo de la salvinia Muy efectivo contra Salvinia molesta La larva barrena los rizoma y provoca que se desintegre. El adulto se alimenta de las yemas de crecimiento evitando su crecimiento. Mide 2-3 mm Vive debajo de la hoja en contacto con el agua. Ciclo vida 45-54d Huevo 10d Larva 21-30d Pupa 14 d USDA, ARS Control efectivo en Australia,  Nueva Guinea,  India, Sri Lanka,
Release of Salvinia weevil in Dorado Golf Pound
Releases of Cyrtobagoussalviniae in Puerto Rico This insect  is not established in the Island, thus no effect has been detected so far. Possible explanation may be the low release number or  different climatic conditions .
Water lily problem observed in Cabo Rojo Wild Life Refugee, DRNA
Hydrilla verticilliata in Puerto Rico 2001
Lakes with aquatic weeds  Lake 			aquatic weeds Carraizo		waterhyacinth, water lettuce Dos Bocas	waterhyacinth Caonillas		Mimosa pellita Guajataca	smartweed Guayabal	waterhyacinth, water lettuce Patillas Lake	smartweed  Carite, Luchetii, Garzas & Cerillos  no aquatic weed
Patillas Lake Guajataca Lake Polygonum spp., smartweed

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Importancia de las malezas acuaticas y su control en PR