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1.
Seventeen isolates of Metarhizium anisopliae (Metschnikoff) Sorokin and two isolates of Beauveria bassiana (Balsamo) Vuillemin were evaluated for their pathogenicity against the tobacco spider mite, Tetranychus evansi Baker & Pritchard. In the laboratory all the fungal isolates were pathogenic to the adult female mites, causing mortality between 22.1 and 82.6%. Isolates causing more than 70% mortality were subjected to dose–response mortality bioassays. The lethal concentration causing 50% mortality (LC50) values ranged between 0.7×107 and 2.5×107 conidia ml−1. The lethal time to 50% mortality (LT50) values of the most active isolates of B. bassiana and M. anisopliae strains varied between 4.6 and 5.8 days. Potted tomato plants were artificially infested with T. evansi and treated with B. bassiana isolate GPK and M. anisopliae isolate ICIPE78. Both fungal isolates reduced the population density of mites as compared to untreated controls. However, conidia formulated in oil outperformed the ones formulated in water. This study demonstrates the prospects of pathogenic fungi for the management of T. evansi. 相似文献
2.
Studies on the reproduction, longevity and life table parameters of Iphiseius degenerans (Berlese) were carried out under laboratory conditions of 25 ± 1 °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 Tetranychus 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.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%.This revised version was published online in May 2005 with a corrected cover date. 相似文献
3.
Three mite species are frequently found on vegetable crops in Italy: the pest Tetranychus urticae Koch (Acari: Tetranychidae), the predator Neoseiulus californicus (McGregor) (Acari: Phytoseiidae) and the unspecialised feeder Tydeus californicus (Banks) (Acari: Tydeidae). In laboratory trials, the direct and residual effects of six insecticides recommended for the control of aphids, whiteflies and thrips in vegetable crops, (Biopiren® plus (pyrethrins), Confidor® (imidacloprid), Oikos® (azadirachtin), Plenum® (pymetrozine), Naturalis® (Beauveria bassiana) and Rotena® (rotenone)), were evaluated for the three mite species. All the products affected the mites and their effect was often favourable towards T. urticae and unfavourable towards N. californicus and T. californicus. Rotenone was more toxic to eggs than females of T. urticae. It was highly toxic to N. californicus and caused the death of all treated females of T. californicus. Pyrethrins and imidacloprid increased T. urticae fecundity, but decreased fecundity of N. californicus. Imidacloprid decreased T. californicus fecundity more than pyrethrins. Beauveria bassiana was not toxic to T. urticae and T. californicus, but induced high mortality in the progeny of treated females of N. californicus. Azadirachtin and pymetrozine were the least toxic to T. urticae and N. californicus, but decreased production of larvae in T. californicus. Implications for integrated pest management on vegetables are discussed. 相似文献
4.
Twenty-three isolates of Metarhizium anisopliae (Metschnikoff) Sokorin and three isolates of Beauveria bassiana (Balsamo) Vuillemin (Ascomycota: Hypocreales: Clavicipitaceae) were assessed for their virulence against the two-spotted
spider mite, Tetranychus urticae Koch (Acari: Tetranychidae). Based on the screening results, nine isolates of M. anisopliae and two isolates of B. bassiana were tested for their virulence against young adult (1- to 2-day-old) female T. urticae at constant temperatures of 20, 25, 30 and 35°C. At all temperatures tested, all the fungal isolates were pathogenic to T. urticae but mortality varied with isolates and temperatures. Fungal isolates were more virulent at 25, 30 and 35°C than at 20°C.
The lethal time to 50% mortality (LT50) and lethal time to 90% mortality (LT90) values decreased with increased temperature. There were no significant differences in virulence between fungal isolates
at 30 and 35°C; however, significant differences were observed at 20 and 25°C. 相似文献
5.
We sampled mites in three apple orchards in Nova Scotia, Canada, that had been inoculated with pyrethroid-resistant Typhlodromus pyri and had a history of Tetranychus urticae outbreaks. The objective of this study was to monitor populations of T. urticae and phytoseiid predators on the ground and in trees and to track dispersal between the two habitats. Pesticides were the
chief cause of differences in mite dynamics between orchards. In two orchards, application of favourably selective acaricides
(abamectin, clofentezine) in 2002, coupled with predation by T. pyri in trees and Neoseiulus fallacis in ground cover, decreased high T. urticae counts and suppressed Panonychus ulmi. By 2003 phytoseiids kept the tetranychids at low levels. In a third orchard, application of pyrethroids (cypermethrin, lambda-cyhalothrin),
plus an unfavourably selective acaricide (pyridaben) in 2003, suppressed phytoseiids, allowing exponential increases of T. urticae in the ground cover and in tree canopies. By 2004 however, increasing numbers of T. pyri and application of clofentezine strongly reduced densities of T. urticae in tree canopies despite high numbers crawling up from the ground cover. Another influence on T. urticae dynamics was the distribution of the phytoseiids, T. pyri and N. fallacis. When harsh pesticides were avoided, T. pyri were numerous in tree canopies. Conversely, only a few N. fallacis were found there, even when they were present in the ground cover and on tree trunks. Low numbers were sometimes due to pyrethroid
applications or to scarcity of prey. Another factor was likely the abundance of T. pyri, which not only competes with N. fallacis, but also feeds on its larvae and nymphs. The scarcity of a specialist predator of spider mites in trees means that control
of T. urticae largely depends on T. pyri, a generalist predator that is not particularly effective in regulating T. urticae.
The Canadian Crown's right to retain a non-exclusive, royalty-free licence in and to any copyright is acknowledged. 相似文献
6.
Lawson-Balagbo LM Gondim MG de Moraes GJ Hanna R Schausberger P 《Experimental & applied acarology》2007,43(1):49-61
The eriophyoid mite Aceria guerreronis Keifer (Eriophyidae), commonly called the coconut mite, is a key pest of coconut fruits. Surveys conducted on coconut palms
in Brazil revealed the predatory mites Neoseiulus paspalivorus DeLeon (Phytoseiidae) and Proctolaelaps bickleyi Bram (Ascidae) as the most commonly associated natural enemies of A. guerreronis on coconut fruits. However, virtually nothing is known about the life history of these two predators. We conducted laboratory
experiments at 25 ± 0.1°C, 70–90% RH and 12:12 h L:D photoperiod to determine the life history characteristics of the two
predatory mites when feeding on A. guerreronis and other potential food sources present on coconut fruits such as Steneotarsonemus furcatus DeLeon (Tarsonemidae), coconut pollen and the fungus Rhizopus cf. stolonifer Lind (Mucoraceae). In addition, the two-spotted spider mite Tetranychus urticae Koch (Tetranychidae) was tested for its suitability as prey. Both predators, N. paspalivorus and P. bickleyi, thrived on A. guerreronis as primary food source resulting in shorter developmental time (5.6 and 4.4 days, respectively), higher oviposition rate
(1.7 and 7.0 eggs/female/day, respectively) and higher intrinsic rate of increase (0.232 and 0.489 per female/day, respectively)
than on any other diet but were unable to develop or lay eggs when fed T. urticae. Coconut pollen and S. furcatus were adequate alternative food sources for N. paspalivorus and Rhizopus for P. bickleyi. We discuss the relevance of our findings for natural and biological control of the coconut mite A. guerreronis. 相似文献
7.
A leaf disc bioassay was employed to examine the effects of temperature and predator age on functional response of an acarophagous
thrips, Scolothrips takahashii Priesner, to hawthorn spider mite, Tetranychus viennensis Zacher, in the laboratory. The results indicated that the predatory thrips exhibited type-II functional responses against
the mites under various temperatures, and that females are more voracious than males. Analysis showed that temperature had
significant effects on the predatory capacity of adult thrips over the range of 20–35 °C. Attack rate in females linearly
increased with temperature while in males it was independent of temperature. Handling times in both males and females decreased
linearly with increasing temperature. Extended response models describing the functional response with temperature incorporated
as a parameter were developed, yielding an estimated maximum numbers of prey attacked at four temperatures were 38.38, 55.06,
71.74 and 88.42 eggs per day for females, and 15.11, 26.11, 37.11 and 48.01 eggs per day for males, respectively. The age
of predator affected both the type of the functional response shown and the magnitude of predation by S.␣takahashii on the spider mite. Females of various ages exhibited Type-II functional responses with similar attack rates, but handling
time prolonged linearly as age increased: the handling times in 15- and 18-d-old females were significantly longer than in
6-d-old thrips. However, Type-I functional responses were determined for males aged 12 d or more; the maximum number of prey
eaten in 24 h decreased as age increased. The implications of the results for the management of hawthorn spider mite are discussed. 相似文献
8.
Martínez-Villar E Sáenz-De-Cabezón FJ Moreno-Grijalba F Marco V Pérez-Moreno I 《Experimental & applied acarology》2005,35(3):215-222
Effects of sublethal azadirachtin exposure to the biological performance of Tetranychus urticae Koch was studied under laboratory conditions. Bioassay was used to asses the effect of different concentrations of azadirachtin on longevity, fecundity, fertility, and offspring development. Azadirachtin (64 and 128 ppm) affected fecundity and mortality but had no effect on fertility and offspring development. A subsequent life-table study with 80 ppm of azadirachtin found that the compound caused a reduction of 50% in survival to adult stage. The peak of reproduction was reached at 5 days causing a decrease in the mean fecundity to almost eight times than of untreated females. The net reproductive rate (R
0), the intrinsic rate of increase (r
m), and the finite rate of increase () of treated females were lower. Treatment showed a negative value of r
m, resulting in a declining population. These results suggest that azadirachtin could be incorporated in Integrated Pest Management (IPM) programmes of T. urticae.This revised version was published online in May 2005 with a corrected cover date. 相似文献
9.
Intracellular bacteria of the genus Wolbachia (alpha Proteobacteria) induce cytoplasmic incompatibility (CI) in many arthropod species, including spider mites, but not
all Wolbachia cause CI. In spider mites CI becomes apparent by a reduced egg hatchability and a lower daughter:son ratio: CI in haplodiploid
organisms in general was expected to produce all-male offspring or a male-biased sex ratio without any death of eggs. In a
previous study of Japanese populations of Tetranychus urticae, two out of three green-form populations tested were infected with non-CI Wolbachia strains, whereas none of six red-form populations harbored Wolbachia. As the survey of Wolbachia infection in T. urticae is still fragmentary in Japan, we checked Wolbachia infection in thirty green-form populations and 29 red-form populations collected from a wide range of Japanese islands. For
Wolbachia-infected populations, we tested the effects of Wolbachia on the reproductive traits and determined the phylogenetic relationships of the different strains of Wolbachia. All but one green-form populations were infected with Wolbachia and all strains belonged to the subgroup Ori when the wsp gene was used to determine the phylogenetic relationships of different strains of Wolbachia. Six out of 29 red-form populations harbored Wolbachia and the infected strains belonged to the subgroups Ori and Bugs. Twenty-four of 29 infected green-form populations and five
of six infected red-form populations induced CI among the hosts. Thus, CI-Wolbachia strains are widespread in Japan, and no geographical trend was observed in the CI-Wolbachia. Although three red-form populations harbored other intracellular bacteria Cardinium, they did not affect host reproduction. 相似文献
10.
Marcic D 《Experimental & applied acarology》2007,42(2):121-129
Laboratory bioassays were conducted to evaluate the effects of spirodiclofen on life history and life-table parameters of
two-spotted spider mite (Tetranychus urticae Koch) females treated at pre-ovipositional period with a series of acaricide concentrations starting with the concentration
discriminative for eggs and immatures i.e. the lowest concentration that causes 100% mortality of those stages. After a 24 h
exposure, the proportion of females that survived treatments was 0.71 (6 mg/l), 0.51 (12 mg/l), 0.41 (24 mg/l), 0.30 (48 mg/l)
and 0.25 (96 mg/l). At the end of the trial, the survival rate of females treated with the lowest concentration was significantly
lower than the survival rate of untreated females but it remained above that of females treated with higher concentrations.
Total fecundity/fertility significantly decreased as concentrations of spirodiclofen increased. Viable eggs were laid by females
treated with 6, 12 and 24 mg/l, and total fertility was reduced by 42, 84 and 97%, respectively. Compared with control, the
gross fecundity/fertility of the treated females was significantly reduced throughout the trial, except in females treated
with 6 mg/l. All concentrations caused a significant reduction in the net fecundity/fertility throughout the trial. The females
treated with 12 mg/l had significantly reduced net reproductive rate (R
0 = 6.45), compared to females treated with 6 mg/l (R
0 = 23.35) and to untreated females (R
0 = 28.92); there was no significant difference between the last two treatments. The intrinsic rate of increase (r
m
) and finite rate of increase (λ) were significantly reduced in treated females (r
m
= 0.141, λ = 1.156 and r
m
= 0.214, λ = 1.232; 12 and 6 mg/l, respectively), compared to control (r
m
= 0.251, λ = 1.276). The reduction was significantly greater in females treated with the highest concentration. As a result of the lowered
r
m
, the doubling time in treated females was significantly extended. Sublethal effects of spirodiclofen and its impact on T. urticae management are discussed. 相似文献
11.
Erika P. J. Britto Manoel G. C. GondimJr. Jorge B. Torres Komi K. M. Fiaboe Gilberto J. Moraes Markus Knapp 《BioControl》2009,54(3):363-368
Predatory behaviour and reproductive output of the ladybird beetle Stethorus tridens Gordon as function of the tomato red spider mite (TRSM), Tetranychus evansi Baker & Pritchard, densities was investigated in the laboratory. Adult female of S. tridens were isolated in cylindrical plastic arenas, containing a leaf disc of Solanum americanum Mill. with 5, 20, 40, 60, 80 or 100 T. evansi nymphs. The number of prey consumed and eggs laid were evaluated daily for ten consecutive days, starting at the oviposition.
Oviposition of S. tridens was positively correlated with prey consumption and lower threshold prey consumption for S. tridens laying eggs was 16.3 mites per day. The instantaneous rate of attack (ca. discovery area) and the handling time were 0.0062 h−1 and 0.83 h, and 0.00254 h−1 and 0.78 h, respectively, for predators at the 1st- and 10th-oviposition day. The predator exhibited a type II functional
response at 1st- and 10th-oviposition day with a maximum consumption per predator of 33 T. evansi nymphs per day at the highest prey density. The ladybird beetle S. tridens is often collected associated with red spider mite colonies on solanaceous wild plants and the results suggest the potential
of this ladybird beetle to control T. evansi in tomatoes crops.
Handling editor: Eric Lucas. 相似文献
12.
The predatory mite Typhlodromus bagdasarjani Wainstein and Arutunjan (Acari: Phytoseiidae) is an indigenous and widespread species of the Middle East fauna. In this paper
we assess the effect of temperature on developmental rate and reproduction potential of T. bagdasarjani under laboratory conditions. The development of this species was determined at 15, 20, 25, 30, 35 and 37.5 ± 1°C, 60 ± 10%
RH and L16:D8 h photoperiod. The total developmental time averaged 28.2, 15.0, 8.9, 7.6, 7.2 and 7.4 days at 15–37.5°C, respectively,
when feeding on immature stages of two-spotted spider mite, Tetranychus urticae Koch. The lower developmental threshold (T
0
) and thermal constant (K) for the development of this predator were estimated 9.2°C and 162 degree-days by the Ikemoto linear model. The life table
parameters were estimated at 15–35°C. The shortest life span of females at 35°C was 45.0 days, followed by 50.7, 50.9, 103.3
and 136.8 days at 30, 25, 20 and 15°C, respectively. Mated females laid on average 19.9, 26.3, 41.1, 39.6 and 31.3 eggs per
female at 15–35°C, respectively. The intrinsic rate of increase (r
m
) and finite rate of increase (λ) increased significantly with increasing temperature. The r
m
values ranged from 0.021 (15°C) to 0.186 (35°C) days−1. The highest value of net reproductive rate (R
0) was 13.6 females progeny/female/generation at 25°C. The results demonstrated that T. bagdasarjani is well adapted to high temperatures. However, the efficiency to control spider mites may be affected by behavioral characteristics
of the predator and its prey under real conditions. 相似文献
13.
Raquel Abad-Moyano Alberto Urbaneja Daniela Hoffmann Peter Schausberger 《Experimental & applied acarology》2010,50(4):329-341
The two-spotted spider mite, Tetranychus urticae, is one of the most problematic phytophagous pests in Spanish clementine orchards. The most abundant predatory mites in this
ecosystem are Euseius stipulatus, Phytoseiulus persimilis and Neoseiulus californicus. Euseius stipulatus is dominant but poorly adapted to utilize T. urticae as prey. It mainly persists on pollen and citrus red mite, Panonychus citri. A recent study suggested that the more efficacious T. urticae predators P. persimilis and N. californicus are negatively affected by lethal and non-lethal intraguild interactions with E. stipulatus. Here, we investigated the potential of N. californicus and P. persimilis to colonize and thrive on young clementine trees infested by T. urticae in presence and absence of E. stipulatus. Presence of E. stipulatus interfered with establishment and abundance of P. persimilis and negatively affected the efficacy of N. californicus in T. urticae suppression. In contrast, the abundance of E. stipulatus was not affected by introduction of a second predator. Trait-mediated effects of E. stipulatus changing P. persimilis and N. californicus behavior and/or life history were the most likely explanations for these outcomes. We conclude that superiority of E. stipulatus in intraguild interactions may indeed contribute to the currently observed predator species composition and abundance, rendering
natural control of T. urticae in Spanish clementine orchards unsatisfactory. Nonetheless, stronger reduction of T. urticae and/or plant damage in the predator combination treatments as compared to E. stipulatus alone indicates the possibility to improve T. urticae control via repeated releases of N. californicus and/or P. persimilis. 相似文献
14.
A survey for natural entomopathogenic fungi of two spotted spider mite (Tetranychus urticae) adults was made in Erzurum, Turkey, during the period 2006. Tetranychus urticae (65.8%) infected with a strain of the fungus Cladosporium cladosporioides were found. Thirteen isolates of C.
cladosporioides were assessed against T. urticae, in a single dose (8 × 106 conidia ml −1), laboratory bioassay on bean leaflets. The total mortality percentage caused by C. cladosporioides isolates varied from 50.95 to 74.76% and LT50 values ranged from 2.34 to 3.90 days. The results revealed that isolates of C. cladosporioides were effective against two spotted spider mite. This is the first record of natural infection of T. urticae by C.
cladosporioides. 相似文献
15.
Prey stage preference of female Kampimodromus aberrans (Oudemans) (Phytoseiidae) at constant densities of different stages of Tetranychus urticae Koch (Tetranychidae), functional response types and parameters of the predator females to the varying densities of eggs,
larvae, protonymphs and deutonymps of T. urticae were determined in order to establish its potential for the mite biological control. Experiments were conducted at 25 ± 1°C,
65 ± 10% RH and 16:8 (L:D) photoperiod. Our results indicated that the predator consumed significantly more prey larvae than
other prey stages. Functional response type of predator was determined by a logistic regression model. The predator exhibited
a Type II response on all prey stages. The attack rate (α) and handling time (T
h
) coefficients of a Type II response were estimated by fitting a “random-predator” equation to the data. The lowest estimated
value α and the highest value of T
h
(including digestion) were obtanined for the predator feeding on deutonmph. The lowest value of T
h
were obtained for the predator feeding on prey larvae, but the attack rate value obtained on larva wasn’t different than
that obtained on egg and protonymph. According to our results, K. aberrans could be an efficient biological control agent of T. urticae at least at low prey densities. However, further field based studies are needed to draw firm conclusions. 相似文献
16.
As it walks, the two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae) spins a trail of silk threads, that is followed by the predatory mite, Neoseiulus womersleyi Schicha (Acari: Phytoseiidae). Starved adult female N. womersleyi followed T. urticae trails laid down by five T. urticae females but did not follow a trail of one T. urticae female, suggesting that the amount of spun threads and their chemical components should correlate positively with the number
of T. urticae individuals. To examine whether chemical components of T. urticae trails are responsible for the predatory mite’s trail following, we collected separate T. urticae threads from the exuviae and eggs, and then washed the threads with methanol to separate chemical components from physical
attributes of the threads. Female N. womersleyi did not follow T. urticae trails that had been washed with methanol but contained physical residues, but they did follow the direction to which the
methanol extracts of the T. urticae trails was applied. These results suggest that the predatory mite follows chemical, not physical, attributes of T. urticae trails. 相似文献
17.
Takeshi Shimoda 《Experimental & applied acarology》2010,50(1):9-22
Herbivore-induced plant volatiles (HIPVs) emitted from lima bean leaves infested with the two-spotted spider mites Tetranychus urticae strongly attract the predatory mites Neoseiulus californicus. Among these HIPVs, methyl salicylate and linalool can attract the predators. Three green-leaf volatiles (GLVs) of (Z)-3-hexen-1-ol, (Z)-3-hexenyl acetate and (E)-2-hexenal, found in the odor blends from T. urticae-infested leaves and physically damaged leaves, can also attract the predators. To search for a strong predator attractant,
the olfactory responses of N. californicus to each synthetic compound or their combinations were investigated in a Y-tube olfactometer. When presented a choice between
a mixture of the five compounds (i.e. the two HIPVs and the three GLVs) and T. urticae-infested leaves, N. californicus did not discriminate between these odor sources. The same trend was observed when either a mixture of the two HIPVs or methyl
salicylate vs. T. urticae-infested leaves were compared. In contrast, the predators preferred T. urticae-infested leaves to linalool, each of the three GLVs, or a mixture of the three GLVs. These results indicated that methyl
salicylate is a strong predator attractant, and its potential attractiveness almost equaled that of the blend of HIPVs from
T. urticae-infested leaves. 相似文献
18.
Tetranychus turkestani Ugarov and Nikolskii and Tetranychus urticae Koch RF (red form) (Acari: Tetranychidae) are closely related species. Previously, the two species were found in separate
agricultural habitats in Israel. Here, additional collections were undertaken and mixed populations of the two species were
found. Manipulation experiments were conducted in order to test whether sexual interactions occur when T. turkestani and T. urticae RF share the same host. Interspecific crosses showed that the two species are capable of producing viable F1 females, but that these females are sterile as their F2 eggs failed to hatch. This indicates a post-zygotic reproductive barrier, supporting the current placement of T. turkestani as a separate taxon. Mating behavior parameters revealed that males of both species courted virgin conspecific and heterospecific
females at the same rate and readily tried to copulate with them. Female mate recognition seemed to be more reliable in T. turkestani than in T. urticae RF as the number of copulations was significantly higher and their duration significantly shorter in the T. turkestani interspecific (T. turkestani ♀ × T. urticae RF ♂) as compared to the intraspecific crosses, a phenomenon not observed in T. urticae RF. In mixed cultures, a significant reduction in female production was observed for T. urticae RF but not for T. turkestani, suggesting an asymmetric reproductive interference effect in favor of T. turkestani. The long term outcome of this effect is yet to be determined since additional reproductive factors such as oviposition rate
and progeny survival to adulthood may reduce the probability of demographic displacement of one species by the other in overlapping
niches. 相似文献
19.
Hosseini M Hatami B Saboori A Allahyari H Ashouri A 《Experimental & applied acarology》2005,37(3-4):173-181
The deutonymphs of Allothrombium pulvinum Ewing (Acari: Trombidiidae) are among the most important natural enemies of spider mites in North, North East and West Iran.
In this study, maximum predation rate and preference experiments were conducted with A. pulvinum deutonymphs on apple leaf discs, to determine their preference for either of two spider mite species: Amphitetranychus viennensis (Zacher) and Tetranychus urticae Koch (Acari: Tetranychidae). Maximum predation rate tests showed that the predatory mite consumed more eggs and females of
T. urticae than of A. viennensis. Furthermore, the Manly’s preference index for eggs and females of T. urticae confirmed that T. urticae were the preferred prey. The functional response of A. pulvinum deutonymphs on females of T. urticae was examined over a 24-h period. Predation of A. pulvinum deutonymphs presented with females of T. urticae followed a type III functional response. Estimated handling time for the predatory mites was 4.51 h and attack coefficient
b, which describes the changes in attack rate with prey densities in a type III functional response, was 0.021. 相似文献
20.
Aceria guerreronis Keifer (Acari: Eriophyidae) is a major pest of coconut fruits (Cocos nucifera L.) in many countries of the Americas, Africa, and parts of Asia. Considerable attention has been given to studies of biological
control agents of A. guerreronis. Proctolaelaps bulbosus Moraes, Reis and Gondim Jr. is a predator recently discovered in association with A. guerreronis. Nothing is known about its biology. The aim of this study was to determine suitable food sources for P. bulbosus, among items commonly found on coconut fruits, including A. guerreronis. Food sources evaluated included the mites A. guerreronis, Steneotarsonemus concavuscutum Lofego and Gondim Jr., and Tyrophagus putrescentiae (Schrank), the fungus Rhizopus aff. stolonifer (Ehrenb.) Vuill and coconut pollen; the mite Tetranychus urticae Koch was also included in the assessments, for being a commonly used prey for mass production and laboratory rearing of predatory
mites. Proctolaelaps
bulbosus was able to develop up to adulthood when fed A. guerreronis,
R. aff. stolonifer and T. putrescentiae. It had the highest population growth rates when feeding on the former (R
o = 17.5; r
m = 0.392). These results indicate that A. guerreronis is the most suitable food for P. bulbosus among the possible food sources found on coconut fruits and that P. bulbosus can survive in the absence of eriophyid using R. aff. stolonifer as a food source. 相似文献