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Vol. 34, No. 2 Internat. J. Acarol. 151<br />

EVALUATION OF INFESTING FIELD BINDWEED (CONVOLVULUS ARVENSIS L.)<br />

WITH ACERIA MALHERBAE NUZZACI (ACARI: ERIOPHYIDAE) UNDER<br />

GLASSHOUSE CONDITIONS<br />

Silvia Rodríguez-Navarro, 1 Antonio Flores-Macías 1 and Gustavo Torres-Martínez 2<br />

1. Departamento de Producción Agrícola y Animal, UAM-X, Calzada del Hueso No. 1100, Col. Villa Quietud,<br />

CP 04960, México, D. F. (e-mail: snavarro@correo.xoc.uam.mx; floresuam@prodigy.net.mx); 2. Unidad de Roedores,<br />

Aves y Malezas, Dir. Gral. de Sanidad Vegetal, SENASICA, Guillermo Pérez Valenzuela No. 127. Col. Coyoacan,<br />

CP 04000, México (e-mail: gtorres@senasica.sagarpa.gob.mx).<br />

ABSTRACT - A study was conducted under glasshouse conditions to determine the most effective method<br />

of infesting Convolvulus arvensis L. with the mite Aceria malherbae (Acari: Eriophyidae). Seven treatments<br />

were included with nine replications: 50, 150 and 200 individuals manually transferred; stems infested<br />

with 3, 5 and 7 galls and a non-treated control. A number of infested stems and galls per plant were<br />

evaluated. One hundred and fifty individuals manually transferred was the best treatment for both variables.<br />

A high correlation (R² = 0.969) between infested stems and galls per plant was found.<br />

Key words - Acari, Eriophyidae, field bindweed (Convolvulus arvensis L.), Aceria malherbae Nuzzaci, infestation,<br />

Mexico.<br />

INTRODUCTION<br />

Appropriately designed biological control programs<br />

against alien weed species may be the best feasible methods<br />

for controlling weeds which significantly affect<br />

crops. This is the case with field bindweed, Convolvulus<br />

arvensis L., where conventional control methods have<br />

been exhausted or are regarded as ineffective. In Mexico<br />

this weed affects all agricultural lands in the state of<br />

Sonora and the Northeast (Mart�nez-Diaz, 2003) with<br />

losses attributed to field bindweed in wheat crops along<br />

the coast of Hermosillo in the state of Sonora alone as<br />

high as 18 to 73% (Mart�nez-Diaz, 2001, 2002). Aceria<br />

malherbae Nuzzaci (Acari: Eriophyidae) is one of four<br />

species in Aceria which attack field bindweed in Greece,<br />

Italy and Spain (Nuzacci et al., 1985). Because of its high<br />

specificity this gall-forming mite survives on just a few<br />

species of Convolvulus and Calystegia (Rosenthal, 1983).<br />

In Texas, U.S.A., it was established successfully (Boldt<br />

and Sobhian, 1993) and was released in various localities<br />

in New Mexico, U.S.A. (Lauriault et al., 2002). In addition,<br />

it established in Alberta, Canada (McClay et al.,<br />

1999). As an alternative control option against the problem<br />

caused by field bindweed (in Mexico), a biological<br />

control research project was launched including the intro-<br />

duction, reproduction and establishment of A. malherbae<br />

(Rodríguez et al., 2004). The key issues in this project<br />

were designing innovative rearing techniques adapted to<br />

the particular requirements of A. malherbae and C.<br />

arvensis to ensure successful release and colonization of<br />

the mite in the cultivation methods used in this study.<br />

Two infestation methods were evaluated to determine the<br />

most promising methods for the release and establishment<br />

of populations of the biological control agent (A. malherbae)<br />

on plants of field bindweed (C. arvensis).<br />

MATERIALS AND METHODS<br />

This work was conducted under glasshouse conditions<br />

in the Centro Nacional de Referencia en Roedores,<br />

Aves y Malezas in Cuernavaca, Morelos, Mexico where a<br />

breeding colony of A. malherbae was maintained on field<br />

bindweed plants that originated from Hermosillo, Sonora,<br />

Mexico. Plants used in the experiments were reared from<br />

seeds which were sown in plastic pots, 17 cm in diameter<br />

and 20 cm deep. One seed was placed at the surface of<br />

each quarter and one in the middle of each pot; 80 ml of<br />

water was provided four times per day by means of drip<br />

irrigation regulated by an automatic programmable applicator.<br />

In a randomly designed experiment seven treat-


152 Rodr�guez-Navarro et al. 2008<br />

Table 1. Monthly temperature and humidity in the<br />

glasshouse.<br />

ments with nine replications were evaluated. In the first<br />

three treatments, mites were transferred manually (50,<br />

150 and 200 individuals) to the stems of field bindweed<br />

(McClay et al., 1999); in another three treatments infested<br />

stems with 3, 5 or 7 galls were twisted around healthy<br />

stems of field bindweed (Rodr�guez et al., 2004; Lauriault<br />

et al., 2002). For the final treatment, no plants were infested<br />

as the controls.<br />

Fifteen days after infestations a random sample was<br />

taken to check for the presence of symptoms on the<br />

treated plants. Mite specimens were mounted on slides using<br />

Hoyer’s medium and identified by comparison with<br />

A. malherbae characteristics (Nuzzaci et al., 1985).<br />

Sampling - The number of galls and the number of<br />

stems with galls were counted from all samples taken at<br />

15 day intervals from each of the pots. Mean temperature<br />

and humidity data for the duration of the trial were obtained<br />

from sensors connected to a Hobo H21-001<br />

climatologic station.<br />

Statistical analyses - To corroborate the normal<br />

distribution of data, the Kolmogorov-Smirnov; Cramervon<br />

Mises and Anderson-Darling (SAS, 2001) methods<br />

were used. Subsequently differences between sample<br />

means were tested by ANOVA and a regression analysis<br />

was done.<br />

RESULTS AND DISCUSSION<br />

Because sample data did not represent a normal distribution<br />

despite transformation, the analysis of variance<br />

was not applied to the mean values, and instead the<br />

non-parametric Kruskal-Wallis (Zar, 1996) method was<br />

applied. According to Fig. 1, the selected ranges of the<br />

samples used in the comparison representing the various<br />

infested stems were not statistically different. Nevertheless<br />

a positive response was observed with all the treatments<br />

except for the controls and the treatment with infested<br />

stems with three galls each. The treatment with 150<br />

mites, overall, produced the highest number of infested<br />

stems (Fig. 2).<br />

The non-parametric tests used for the variation of<br />

galls per plant, again, did not indicate any statistical differences<br />

between the treatments. Similarly, as mentioned<br />

before, the number of galls per plant in the controls and in<br />

the treatment using 3 galls per stem showed no response.<br />

The treatment with 150 mites again presented the highest<br />

number of galls per plant. As was the case in the controls,<br />

the absence of any response to the treatment using three<br />

galls per stem could have been the result of the low survival<br />

of A. malherbae.<br />

The regression analysis (Fig. 3) to determine the relation<br />

between the number of infested stems and the num-<br />

Fig. 1. Infested stems for the various treatments (mean values). Bars with the same letter indicate no statistical differences<br />

between treatments.


Vol. 34, No. 2 Internat. J. Acarol. 153<br />

Fig. 2. Galls per plant (mean values). Bars with the same letter indicate no statistical difference between treatments.<br />

ber of galls per plant showed a positive linear tendency<br />

(R² = 0.969) indicating that the increase in the number of<br />

galls attached to plants resulted in a 96.9% increase in the<br />

number of infested stems: the more infested stems, the<br />

more galls are formed on them.<br />

The conditions under which the experiments were<br />

conducted could have limited the infestations and damage<br />

caused to field bindweed. Hammon (2007) mentioned an<br />

inverse relationship between the amount of irrigated water<br />

applied and the success of infestations. The daily application<br />

to each pot of 320 ml of water and the high humidity<br />

(Table 1) which occurred during the experiments<br />

could have affected the settling success of the mites, negatively.<br />

In these experiments the damage caused by A.<br />

malherbae on the leaves of field bindweed was similar to<br />

the damage observed by McClay et al. (1999) who reported<br />

that over a period of one to four years, A.<br />

malherbae caused light to severe damage to field bindweed<br />

under field conditions.<br />

Another important consideration is that when the<br />

eriophyids are transferred one by one, it is guaranteed that<br />

only A. malherbae is present in the new colony. However,<br />

this method may cause dehydration if the mites are exposed<br />

to direct heat or they may be injured while being<br />

transferred. Also, when transfering by galls it is necessary<br />

to clean the galls to avoid thrips, white flies, or spider<br />

mites. The advantages of using this method are a higher<br />

Fig. 3. Positive linear relationship in the number of galls dependent on the number of infested stems.


154 Rodr�guez-Navarro et al. 2008<br />

number of eggs and different biological stages of A.<br />

malherbae, plus the population grows satisfactorily.<br />

ACKNOWLEDGEMENTS<br />

The authors wish to thank Dr. Alec McClay,<br />

McClay Ecoscience, 15 Greenbriar Crescent, Sherwood<br />

Park, AB, Canada and Dr. Helmuth Zimmermann and Associates<br />

(Central) P.O. Box 974, Faerie Glen Pretoria<br />

0043, South Africa, for review and many suggestions on<br />

the manuscript.<br />

REFERENCES<br />

Boldt, P. E. and R. Sobhian. 1993. Release and establishment<br />

of Aceria malherbae Nuzzaci (Acari: Eriophyidae)<br />

for control of field bindweed in Texas. Environ.<br />

Entomol. 22(1): 234-237.<br />

Hammon, R. 2007. Managing field bindweed with the<br />

bindweed mite Aceria malherbae. Horticulture Colorado<br />

State Extension. Disponible in: http://www.<br />

coopext.colostate.edu/.<br />

Lauriault, L., G. J. Michels, Jr. and D. C. Thompson.<br />

2002. Use of Aceria malherbae gall mites for biological<br />

control of field bindweed (Convolvulus arvensis).<br />

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Hermosillo, Son. México. 84-89.<br />

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Costa de Hermosillo. INIFAP. 140 pp.<br />

Martínez-Díaz, G. 2002. Perspectivas en el control biológico<br />

de correhuela perenne (Convolvulus arvensis<br />

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*****<br />

lógico, Simposio Internacional Control Biológico<br />

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Martínez-Díaz, G. 2003. La correhuela perenne (Convolvulus<br />

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Investigación Regional del Noroeste Campo Experimental<br />

Costa de Hermosillo. INIFAP. México. 172<br />

pp.<br />

McClay, A. S., J. L. Littlefield and J. Kashefi. 1999. Establishment<br />

of Aceria malherbae (Acari: Eriophyidae)<br />

as a biological control agent for field bindweed<br />

(Convolvulaceae) in the Northern Great<br />

Plains. Canad. Entomol. 131: 541-547.<br />

Nuzzaci, G., T. Mimmocchi and S. L. Clement. 1985. A<br />

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Convolvulus arvensis L. (Convolvulaceae) with<br />

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Rodr�guez, N. S., J. G. M. Torres and J. O. Olivarez.<br />

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(2): 153-155.<br />

Rosenthal, S. S. 1983. Current status and potential for biological<br />

control of field bindweed with Aceria convolvuli,<br />

pp 57-60. In: Hoy, M. A., G. L. Cunningham<br />

and L. Knutson (Eds.). Biological Control of<br />

Pests by Mites. Univ. Calif. Agric. Exp. Atn. Publ.<br />

3304.<br />

SAS. 2001. SAS User´s Guide: Statistics. SAS Institute<br />

Inc. Version 8 Edition, North Carolina, Cary.<br />

Zar, Jerrold. 1996. Biostatistical Analysis. Ed. Prentice-<br />

Hall. Englewood Cliffs, N. J.

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