Amblyseius degenerans (Berlese, 1889)
(= Iphiseius degenerans)
Alóctono (África y algunos paises europeos mediterráneos)
|Phylum Arthropoda von Siebold, 1845Subphylum Cheliceromorpha Boudreaux, 1978Supercl. Chelicerata Heymons, 1901Clase Arachnida Lamarck, 1801Subcl. Acari Micrura Hansen & Sorensen, 1904Infracl. Acaromorpha Dubinin, 1957Superord. Parasitiformes Reuter, 1909Ord. mesostigmataSubord. DermanyssinaSuperfam. Ascoidea Oudemans, 1905Fam. Phytoseiidae Berlese, 1916Subfam. Amblyseiinae|
Fuente: Consejería Agricultura y pesca Junta Andalucía
Este ácaro depredador ejerce su control sobre varias especies de trips, como Frankliniella occidentalis y Trips tabaci en cultivos de algunas solanáceas bajo abrigo.
Según la EPPO el origen de la distribución del fitoseido Amblyseius degenerans se sitúa en África y Europa, encontrándose actualmente en Europa muy repartido por numerosos países. La misma fuente cita su utilización como organismo beneficioso comercial desde 1993 en cultivos bajo abrigo de numerosos países del Mediterráneo y Europa, entre ellos España.
Los huevos, depositados en grupos, son inicialmente transparentes, volviéndose con el transcurso del tiempo parcialmente marrones. No se distinguen de los huevos de Amblyseius cucumeris (Oudemans).
Las larvas de A.degenerans son de color marrón y se caracterizan por presentar en el dorso del tórax un dibujo en forma de X.
El adulto presenta una coloración marrón oscuro y mide 0.7mm de longitud, siendo por tanto ligeramente más grande que A.cucumeris. Gracias a su color oscuro y su movilidad es fácilmente localizable tanto en la hoja como en la flor.
Biología y Ecología
El ciclo biológico de A.degenerans pasa por los estados de huevo, larva, 2 estadíos ninfales (proto y deutoninfa) y finalmente el estado adulto.
Se diferencia de A.cucumeris, entre otros detalles, en que sus poblaciones permanecen más en las flores donde pueden desarrollarse sólo con polen, y en que sus huevos son más resistentes a las bajas humedades por tanto puede seguir desarrollándose en verano
Otra característica que posee el fitoseido A.degenerans es que no entra en diapausa, por lo que puede realizar un control eficaz sobre el trips en invierno.
A.degenerans se alimenta principalmente de larvas de trips. Las larvas de A.degenerans casi no se alimentan y no tienen movilidad, permaneciendo cerca del lugar donde nacieron, hasta pasar al estado de proto y deutoninfa muy móviles y activos depredadores, al igual que los adultos. Los ácaros perforan su presa vaciando completamente su contenido. El consumo diario medio es de 4-5 larvas de trips al día.
Es un depredador no específico, pudiéndose alimentar además de trips y polen, de ácaros tetraníquidos.
Los huevos pueden verse en grupos, adheridos a los pelos de los nervios en el envés de las hojas.
Amblyseius degenerans está registrado en España bajo los siguientes productos comerciales
|Ficha técnica||nombre comercial||Empresa||Presentación||contenido unitario garantizado|
|DEGENERANS-SYSTEM||Biobest Sistemas Biológicos S.L.||Tubo con vermiculita
Plagas que controla
Está recomendado en el control de araña roja, araña blanca y algunas especies de trips:
Trips tabaci (trips de la cebolla)
|Frankiiella occidentalis (Trips de las flores)|
- 2.000 individuos/Ha. / 20 ejemplares por suelta
Autor: ir. Isabelle Vantornhout
Autor: A. ESPINO, J. BARROSO y A. CARNERO
Bol. San. Veg. Plagas, 14: 55-66, 1988
En un cultivo de pepinos situado en la zona norte de Tenerife se ha intentado aplicar un programa de lucha integrada, con introducción artificial de Encarsia formosa (Hymenóptero Aphelinidae) para control de "mosca blanca" Trialeurodes vaporariorum (Homóptero Aleurodidae) y sueltas puntuales de Iphiseius degenerans (Acari Phytoseidae) para control de [...]
The effect of relative humidity on egg hatch success for Iphiseius degenerans, Neoseiulus californicus and N. cucumeris was described by a binomial model with a parallel slope. The shape of the response differed for Phytoseiulus persimilis and a model with separate parameters gave a significantly better fit. Fitted response curves showed that I. degenerans, N. cucumeris, N. californicus and P. persimilis were ranked by decreasing tolerance to low humidity, with egg mortalities of < 0.5, 3, 12 and 16% respectively at 75-80% RH at 20 degrees C. Egg stage duration for I. degenerans and N. cucumeris was unaffected over the range 60-82% RH. For N. californicus and P. persimilis egg duration was significantly longer at 60 and 70% than for either 82 or 90% RH. No effect of relative humidity was found on the mean life span of adult females when food was available continuously to the mites. N. californicus lived significantly longer (58 days after the first egg was laid) than the other species. No significant difference was observed in mean life span between adult females of I. degenerans and N. cucumeris (25 and 28 days respectively). The mean life span of adult female P. persimilis (19 days) was significantly shorter than the other species. In the absence of both food and water, the survival of adult female mites was reduced to 2-4 days. Survival time was at least doubled when free water was available in the absence of food. Mean survival of adult female mites with water but without food was 10 days for N. cucumeris, 18 days for N. californicus, 6 days for P. persimilis and 4 days for I. degenerans. Survival of adult female N. cucumeris and N. californicus was increased significantly, to 20 and 22 days respectively, when fungal hyphae were present along with water but in the absence of other food.
Michael E de Courcy Williams
Biocontrol and IPM Research Team, Horticulture Research International, Wellesbourne, Warwickshire, CV35 9EF, UK
Exp Appl Acarol 32:1-13. 2004
J D Stark
Puyallup Research and Extension Center, Washington State University, USA
Ecotoxicol Environ Saf 37:273-9. 1997
Acute lethal concentration estimates (72-hr LC50) and population growth rates (7-day instantaneous rate of increase) of two mite species, an herbivore, the two-spotted spider mite Tetranychus urticae Koch, and the generalist predator mite Iphiseius degenerans Berlese, were developed after exposure to two pesticides, dicofol and Neemix. For each pesticide, LC50 estimates for both species were similar, yet the two species exhibited completely different susceptibility when population growth rate was the endpoint evaluated; I. degenerans was much more susceptible than T. urticae to either pesticide. For example, populations of I. degenerans became extinct after exposure to 250-ppm azadirachtin, the active ingredient in Neemix, while T. urticae populations became extinct after exposure to 1000 ppm. A similar relationship was found for dicofol. The no observable effect concentration (NOEC) for population growth rates after Neemix exposure was 4 ppm for I. degenerans and 125 ppm for T. urticae. These NOEC values were equivalent to the acute LC2 for the immature stage of I. degenerans and the acute LC65 for the immature stage of T. urticae. Consequently, populations of T. urticae were able to compensate for high losses of individuals while I. degenerans populations could not compensate for losses. An analysis of reproduction data indicated that unexposed T. urticae produced four to five times more offspring than I. degenerans. This in itself was important because it indicated that I. degenerans was intrinsically more susceptible than T. urticae because similar effects on reproduction would be more devastating to the species with a lower reproductive rate. Results indicate that a species' reproductive potential can greatly influence its susceptibility to toxicants.
Laboratory of Agrozoology, Department of Crop Protection, Faculty of Agricultural and Applied Biological Sciences, Ghent University, Coupure Links 653, B 9000 Ghent, Belgium
Exp Appl Acarol 35:183-95. 2005
Abstract. Studies on the reproduction, longevity and life table parameters of Iphiseius degenerans (Berlese) were carried out under laboratory conditions of 25 +/- 1 degree C, 75 +/- 5% RH and 16L:8D h. As food sources for the predatory mite, Ricinus communis L. pollen, all stages of the spider mite Tetrranchus urticae Koch, Frankliniella occidentalis (Pergande) larvae, and Ephestia kuehniella Zeller eggs were selected. All diets were accepted as food by the adult mites. Female longevity ranged from 29.5 to 42.4 days, the highest value was recorded on a diet of Ephestia eggs. The highest percentage of females escaping the experimental arena was observed on the diet consisting of thrips larvae. The highest oviposition rate (1.9 eggs/female.day) was recorded when the predator was fed on spider mites on an artificial substrate. For other diets, oviposition rates ranged from 1.0 to 1.3 eggs/female.day. The intrinsic rate of natural increase (r(m)) of I. degenerans varied between 0.015 and 0.142 females/female x day. The diet consisting of castor bean pollen resulted in the highest population growth whereas the diet on spider mites brushed off onto a bean leaf arena resulted in the slowest population growth. This can be explained by the inability of the predator to cope with the webbing of T. urticae, and the high escape rate of the progeny when reared on spider mites. The percentage of females in the offspring ranged from 40 to 73%.
Institute for Biodiversity and Ecosystem Dynamics, Department of Population Biology, University of Amsterdam, P O Box 94084, Amsterdam, 1090 GB, The Netherlands
Oecologia 150:699-705. 2007
To prevent predation on their eggs, prey often avoid patches occupied by predators. As a result, they need to delay oviposition until they reach predator-free patches. Because many species allocate energy to egg production in a continuous fashion, it is not clear what kind of mechanism prey use to delay oviposition. We used females of the phytoseiid mite Neoseiulus cucumeris to study these mechanisms. Females were placed in patches with pollen, a food source they use for egg production, and they were exposed to another phytoseiid mite, Iphiseius degenerans, which is an intraguild predator of N. cucumeris juveniles. We found that the oviposition of N. cucumeris females on patches with the predator was lower than on patches without the predator. Cues left by the intraguild predator were not sufficient to elicit such behaviour. Females of N. cucumeris reduced oviposition when exposed to the predator by retaining the egg inside their body, resulting in a lower developmental rate once these eggs were laid. Hence, females are capable of retaining eggs, but the development of these eggs continues inside the mother's body. In this way, females gain some time to search for less risky oviposition sites.
Institute for Biodiversity and Ecosystem Dynamics, Section Population Biology, University of Amsterdam, PO Box 94084, 1090 GB, Amsterdam, The Netherlands
Oecologia 156:797-806. 2008
Herbivores can profit from vectoring plant pathogens because the induced defence of plants against pathogens sometimes interferes with the induced defence of plants against herbivores. Plants can also defend themselves indirectly by the action of the natural enemies of the herbivores. It is unknown whether the defence against pathogens induced in the plant also interferes with the indirect defence against herbivores mediated via the third trophic level. We previously showed that infection of plants with Tomato spotted wilt virus (TSWV) increased the developmental rate of and juvenile survival of its vector, the thrips Frankliniella occidentalis. Here, we present the results of a study on the effects of TSWV infections of plants on the effectiveness of three species of natural enemies of F. occidentalis: the predatory mites Neoseiulus cucumeris and Iphiseius degenerans, and the predatory bug Orius laevigatus. The growth rate of thrips larvae was positively affected by the presence of virus in the host plant. Because large larvae are invulnerable to predation by the two species of predatory mites, this resulted in a shorter period of vulnerability to predation for thrips that developed on plants with virus than thrips developing on uninfected plants (4.4 vs. 7.9 days, respectively). Because large thrips larvae are not invulnerable to predation by the predatory bug Orius laevigatus, infection of the plant did not affect the predation risk of thrips larvae from this predator. This is the first demonstration of a negative effect of a plant pathogen on the predation risk of its vector.
Department of Entomology, Faculty of Agricultural, Food and Environmental Quality Sciences, The Hebrew University of Jerusalem, P O Box 12, 76100, Rehovot, Israel
Exp Appl Acarol 46:183-94. 2008
We review published and unpublished studies conducted in Israel with six acaropathogenic fungi, assayed in order to control the citrus rust mite, Phyllocoptruta oleivora (Ashmead) (CRM). Hirsutella thompsonii Fisher was introduced twice, killed 80-90% of the exposed mites, but due to its requirements for near-saturation humidities was deemed unsuitable for local outdoors conditions. Hirsutella kirchneri (Rostrup) Minter et al. and Hirsutella necatrix Minter et al. were also introduced and assayed against CRM and spider mites, but their efficacy was unsatisfactory. Three indigenous fungi found to be associated with mites, Meira geulakonigii, Meira argovae and Acaromyces ingoldii--all three recently described by Boekhout, Gerson, Scorzetti & Sztejnberg--were assayed against several mites. Meira geulakonigii killed 80-90% of several spider mites and of the CRM, and caused some mortality of Iphiseius degenerans (Berlese), one out of three phytoseiid predators assayed. Mortality was not due to parasitization; extracts from the media in which the fungi had developed caused considerable mite death, suggesting that it was a result of fungal toxins. Data from a field study indicated that spraying blastoconidia of M. geulakonigii on grapefruits infested by CRM significantly reduced pest-incurred damage from 23 to 13%. Applying qRT-PCR methodology indicated that M. geulakonigii was endophytic within sealed grapefruit flowers and in the flavedo of the fruits' peel. Neither in the laboratory nor in the field was any evidence ever obtained that this fungus damaged the plants, leading us to hypothesize that M. geulakonigii serves as a "body guard" of grapefruits (and perhaps other plants as well). All three fungi suffered very little mortality after being exposed to various insecticides and acaricides that are in current local use (with the exception of sulfur). The ability of M. geulakonigii to reduce mite numbers without affecting the host plant, the minimal fungal effect on some predatory mites, its endophytic nature along with the apparent tolerance of M. geulakonigii to many insecticides and acaricides, suggest that this fungus could be suitable for integrated pest management (IPM) program.
Section of Population Biology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands
Oecologia 163:335-40. 201
Theory on intraguild (IG) predation predicts that coexistence of IG-predators and IG-prey is only possible for a limited set of parameter values, suggesting that IG-predation would not be common in nature. This is in conflict with the observation that IG-predation occurs in many natural systems. One possible explanation for this difference might be antipredator behaviour of the IG-prey, resulting in decreased strength of IG-predation. We studied the distribution of an IG-prey, the predatory mite Neoseiulus cucumeris (Acari: Phytoseiidae), in response to cues of its IG-predator, the predatory mite Iphiseius degenerans. Shortly after release, the majority of IG-prey was found on the patch without cues of IG-predators, suggesting that they can rapidly assess predation risk. IG-prey also avoided patches where conspecific juveniles had been killed by IG-predators. Because it is well known that antipredator behaviour in prey is affected by the diet of the predator, we also tested whether IG-prey change their distribution in response to the food of the IG-predators (pollen or conspecific juveniles), but found no evidence for this. The IG-prey laid fewer eggs on patches with cues of IG-predators than on patches without cues. Hence, IG-prey changed their distribution and oviposition in response to cues of IG-predators. This might weaken the strength of IG-predation, possibly providing more opportunities for IG-prey and IG-predators to co-exist.