Bustamante Hernández, A.

Pérez Pacheco, R.

Rodríguez Esperanza, A.

Ruiz Michael, G.

Santamarina Mijares, A.

Revistes Catalanes amb Accés Obert

Miscel.lania Zoologica 19.1 (1 996) 33 
Eff ectiveness of Romanomermis 
culicivorax (Nema toda 
Mermithidae) in Anopheles 
pseudopunctipennis and Culex 
quinquefasciatus (Di ptera, 
Culicidae) in Mexico 
A. Santamarina Mijares, G. Ruíz Michael, 
A. Rodríguez Esperanza, A. Bustamante 
Hernández & R. Pérez Pacheco 
Santamarina Mijares, A., Ruíz Michael, G., Rodríguez Esperanza, A,, Bustamante Hernández, 
A. & Perez Pacheco, R. 1996. Effectiveness of Romanomermis culicivorax (Nematoda, 
Mermithidae) in Anophelespseudopunctipennisand Culex quinquefasciatus(Diptera, Culicidae) 
in Mexico. Misc. Zool., 19.1: 33-37. 
Effectiveness of Romanomermis culicivorax (Nematoda, Mermithidae) in Anopheles 
pseudopunctipennis and Culex quinquefasciatus (Diptera, Culicidae) in Mexic0.- Field 
tests were conducted with Romanomermis culicivorax Ross & Smith, 1978 as control of 
mosquito larvae in three natural sites located in Oaxaca State, Mexico. lnfective nema- 
todes were disseminated at 1000/m2. Both species of mosquito larvae were infected but 
populations of anopheline mosquitoes were more susceptible than culicine. 
Key words: B iolog ical control, Romanomermis culicivorax, Anopheles pseudopunctipennis, 
Culex quinquefasciatus. 
(Rebut: 18 IV 95; Acceptació condicional: 12 IX 95; Acc. definitiva: 9 1 96) 
A. Santamarina Mijares, lnst, de Medicina Tropical «Pedro Kouri)), Autopista Novia del 
Mediodía km 6 1/2 e/ Autopista Nacional y Carretera Central, La Lisa, 1 1500 Ciudad de 
la Habana, Cuba (Cuba).- G. Ruiz Michael, Procuraduria Federal de Proteccidn al Ambiente, 
Palacio Federal, A vda. Independencia 709 Altos, Oaxaca, México (Mexico). -A. Rodrlguez 
Esperanza & A. Bustamante Hernández, Soc. Oaxaqueña de Salud Pública, A. C. Volcanes 
de las Virgenes 307, Col. Volcanes, Oaxaca, México (Mexico).- R. Pérez Pacheco, lnst. 
Politécnico Nacional, CIIDIR-IPN-U, Oaxaca, d Hornos s/n., Xoxocotlán (Oaxaca), A.P. 
674, México (Mexico). 
1996 Museu de Zoologia 
Santarnarina Mijares e t  al. 
lntroduction 
Oaxaca State has a h igh rate o f  malaria. 
This area is situated between parallels 19" 
o f  the  nor th  longitude and rneridians 93" 
and 99" o f  west longitude. Its clirnatic 
conditions such as ternperature and rain- 
fa11 are appropriate fo r  the developrnent 
of  Anopheles pseudopunctipennis Theo- 
bald, 1901 and fo r  the  transrnission by 
Plasmodium vivax Grassi & Feletti, 1890 
and Plasmodium falciparun Welch, 1897. 
Frorn 1988 t o  1994 an intensive prograrn 
against vector A. pseudopunctipennis was 
carried out  in  Oaxaca State, consisting 
o f  application o f  insecticides inside houses 
as antilarvarian treatrnents. Mass treat- 
rnent were carried ou t  in  zones o f  rnajor 
epiderniological risk. 
R. culicivorax has been evaluated suc- 
cessfully against various Anopheles spe- 
cies in  f ie ld conditions (PETERSEN & WILLIS, 
1974; PETERSEN, 1976) and a t  least 52 spe- 
cies o f  rnosquitoes in  their larval stage are 
parasitized in  natural conditions (PETERSEN, 
1973). 
The infective or  pre-parasitic larvae o f  
this nernatode species have a short l i fe  
and rnust f i nd  a larvae o f  t he  host rnos- 
qu i to  between 36 and 48 h after erner- 
gence. The pre-parasitic enters the  larvae 
by cuticular route by rneans o f  a stiletto. 
Seven days later, post-parasites ernerge 
ki l l ing rnosquitoe larvae (PLATZER, 1982). 
This paper describes the results o f  intro- 
ducing the rnerrnithid Romanomermis 
culcivorax in Anopheles albimanus and 
Culex quinquefasciatus natural breeding 
places in  Oaxaca State and evaluates its 
parasitic capacity as biolarvicide. 
Material and Methods 
Three natural sites o f  200, 180 and 150 
m2 situated i n  Oaxaca coast were 
used. The sites were exarnined be- 
fore the  application o f  the  nernatode 
t o  establish t h e  larva1 density o f  A. 
pseudopunctipennis a t  sites 1 and 2 and 
o f  Culex quinquefasciatus Say, 1823 at  
site 3. 
The pre-parasites were obtained frorn 
six laboratory cultures o f  nernatodes pro- 
duced in  the  lnstitute o f  Tropical Medi- 
cine 'Pedro Kouri'. Cultures were f looded 
wi th  distilled water. A total  o f  745,000 pre- 
parasites were deterrnined which were 
Miscel.lania Zoologica 19.1 (1996) 3 5 
Larval dansity/m2 lnfection 72h 
- -- 
nt Post-treatment % Instar~ R 
calculated by volurnetric dilution rnethod was 29°C. Anophelesand Culexrnosquito 
(PETERSEN & WILLIS, 1972). Pre-parasites were larvae (1st-4th) instars were sarnpled 72 h 
transported t o  the field in a 3 1 plastic post-application and 140 larvae per site 
container. The final dilution was rnade (35 larvae per instar) were returned to  the 
wi th water frorn the sites. The pre-para- laboratory and observed under a corn- 
sites were applied at rates of 1000/rn2. Sites pound rnicroscope for nematode infection. 
1, 2 and 3 received 200,000, 180,000 and Mosquito larvae populations were deter- 
150,000 pre-parasites respectively frorn a rnined again seven days later by collect- 
5 1 cornpressed air sprayer (Holder-planta 5, ing sarnples each 2 rn, using a larval net 
Gebr. Holder, Gerrnany) at a pressure of 20 crn in diarneter and 20 crn in depth with 
2 at. a handle of 2 m (DUBITSKIJ, 1978). Data frorn 
Two control sites (I20 and 190 rn2) were field tests presented normal distribution 
esta blished. and were analysed statistically using analy- 
The ternperature at tirne of application sis o f  variance (ANOVA) (p < 0.001) and 
36 Santarnarina Mijares et al. 
Duncan's rnultiple range test (p = 0.05) ing the invasion by the pre-parasitic lar- 
t o  compare the rnean of infection (X) per vae of the nernatode, which exhibits 
larvae (1st-4th) instar. To determine the negative geotropisrn (ROJAS et al., 1987). 
influence of mosquito species and larval Recent observations (Montoya & Gallo, 
instars on the rnean value of infection an unpublished results) indicate that the 
ANOVA of double classification (p < 0.005) merrnithid R. culicivorax shows a high 
was used. infective capacity in larvae of Anopheles 
albimanus Wiedernann, 1821 and Anoph- 
eles nuñez-tovari Gabaldon, 1940, kill- 
Results ing the younger stages within 28 hours, 
and the parasite does not attain a post- 
The ecological characteristics of control parasitic forrn in these larvae. 
sites and study sites pre-treatment are PETERSEN et al., 1978 reported tkat  R. 
shown on table 1. culicivorax was rnass produced for the 
Table 2 shows the total number o f  lar- treatrnent o f  144,000 rn2 of A. albimanus 
vae and larvae density (m2) prior t o  treat- breeding area in Lake Apastepeque in El 
rnent. Salvador. The edges of Lake Apastepeque 
The comparison of rnean values of in- were treated eleven times in seven weeks 
fection by 1-way ANOVA showed differ- t o  control A. pseudopunctipennis and A. 
ences in  al1 sites (p < 0.001): site 1 F = albimanus mosquito larvae. The Anoph- 
17,875, site 2 F = 18,452; site 3 F = 9,091. eles population was reduced and parasit- 
The percentage of larvae infected 72 h ism of merrnithid averaged 94% post-ap- 
post-treatrnent in each site, and the rnean plication. Larvae o f  1st and 2nd instars 
infection for each instar are presented in collected frorn treated sites 1, 2, and 3 
table 2. were dead. The cause was considered t o  
The cornparison of infection rneansfrorn be rnultiparasitism. 
al1 sites by 2-way ANOVA showed signifi- Although C. quinquefasciatus mosquito 
cant differences arnong instars from each larvae showed the lowest rate of parasit- 
specie (F = 9,973; p < 0.001) and between isrn, that of 1st and 2nd instars was the 
bo th  species (F = 22,921; p < 0.001). highest, due the slight chitin forrnation 
Duncan's test showed tha t  3rd-4th in the cuticle which facilitates the pen- 
instars A. pseudopunctipennis and C. etration by the pre-parasites stiletto. 
quinquefasciatusrnosquito larvae differed The percentage of parasitism found in 
frorn 1st-2nd instars, indicating younger A. pseudopunctipennis larvae showed a 
larvae (1, II) were more susceptible t o  in- high pathogenic effect. The incrernent of 
fection than older ones (111, IV). larval density at control sites 1 and 2 was 
Estirnation of larval densities seven days attributed t o  the continua1 hatching of 
post-treatrnent are shown in table 2, as new larvae. The percentage o f  rnortality 
well as percentage of rnortality. observed in A. pseudopunctipennis and 
C. quinquefasciatus larvae and the reduc- 
t ion of larval density at sites 1, 2, and 3 
Discussion showed the possible use of the parasite 
R. culicivorax t o  control these species of 
Younger larval stages of A. pseudopunc- mosquito larvae as an alternative to  cherni- 
tipennk and C. quinquefasciatus were cal control in Oaxaca State, Mexico. 
more susceptible t o  parasitism and A. 
pseudopunctipennis mosquito larvae 
showed the highest index o f  infection. Resumen 
This i s  probably due t o  the fact that the 
latter adopts a horizontal position be- Efectividad de Romanornerrnis culicivorax 
low the water surface, thereby facilitat- (Nematoda, Mermithidae) en Anopheles 
Miscel-lania Zoologica 19.1 (1 996) 
pseudopunctipennis y Culex quinque- 
fasciatus (Diptera, Culicidae) en México 
Se realizaron pruebas de campo con 
Romanomermis culicivorax Ross & Smith, 
1978 como control de larvas de mosqui- 
t o  en tres áreas naturales situadas en el 
estado de Oaxaca, México (tabla 1). Los 
nemátodos infectantes se diseminaron a 
1000/m2. Resultaron infectadas las larvas 
de mosquito de las dos especies, sin 
embargo, las larvas de Anopheles resul- 
taron ser más susceptibles que las de 
Culex (tabla 2). Se observó además que 
los mayores niveles de parasitismo ocu- 
rrieron en los estadios más jóvenes I y II, 
los cuales resultaron más susceptibles a 
la invasión de los preparasíticos infectivos. 
Los valores de pH y temperatura calcu- 
lados en el momento de las aplicaciones 
no influyeron negativamente en la ca- 
pacidad infectiva de los preparasíticos. 
Acknowledgements 
The authors wish t o  thank the members 
o f  the antimalaria campaign o f  Pochutla 
Municipality for  technical assistance 
throughout the experiments. 
References 
DUBITSKIJ, A. M., 1978. Métodos de con- 
t ro l  biológico de los dípteros 
hematófagos en la URSS. T. l. Acad. 
Csi. Kaz. SSR. Alma Atá, Ed. 11265. Ac. 
PETERSEN, J. J., 1973. Role o f  mermithid 
nematodes in  biological control o f  
mosquitoes. Exp. Parasitol., 33: 239-247. 
- 1976. Recycling o f  the nematode Ree- 
simermis nielseni during 1975 in  
Anopheles crucians in  Louisiana. Proc. 
Utah Mosq. Abat. Assoc., 28: 17-18. 
PETERSEN, J. J. & WILLIS, O. R., 1972. Pro- 
cedures for the mass rearing of a mer- 
mithid parasite o f  mosquitoes. Mosq. 
News., 32: 226-230. 
- 1974. Experimental release o f  a mer- 
mithid nematode t o  control Anoph- 
eles mosquitoes in Louisiana. Mosq. 
News., 34: 316-319. 
PETERSEN, J. J., WILLIS, O. R. & CHAPMAN, 
H. C., 1978. Release of Romanomermis 
culicivorax for control of Anopheles 
albimanus in E l  Salvador. 1. Mass Pro- 
duction of nematode. Amer. J. Trop. 
Med. Hyg., 27: 1265-1267. 
PLATZER, E. J., 1982. Biology of mermithid 
and Steinernematidae with vector con- 
trol  potential. Proceedings o f  the lllrd 
lnternational Colloquium on Inverte- 
brate Pathology, 6-10 September 1982: 
374-379. Brighton, Sussex, U. K. 
ROJAS, W., NORTHUP, J., GALLO, O., MONTOYA, 
A. E., F. RESTREPO, M., NIMNICH, C., ARANGO, 
M. & ECHAVARRIA, M., 1987. Reduction of 
malaria prevalence after introduction of 
Romanomermis culicivorax(Mermithidae: 
Nematoda) in larval Anopheles habitats 
in Colombia. Bull. WHO, 65(3): 331-337. 


Effectiveness of Romanomermis culicivorax (Nematoda, Mermithidae) in Anopheles pseudopunctipennis and Culex quinquefasciatus (Diptera, Culicidae) in Mexico

Effectiveness of Romanomermis culicivorax (Nematoda, Mermithidae) in Anopheles pseudopunctipennis and Culex quinquefasciatus (Diptera, Culicidae) in Mexico

Abstract

Similar works

Full text

Available Versions

Revistes Catalanes amb Accés Obert