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1.
Combining pheromone-baited and food-baited traps for insect pest control: Effects of additional control by parasitoids 总被引:1,自引:0,他引:1
Hugh J. Barclay 《Researches on Population Ecology》1991,33(2):287-306
Summary Two age-structured population dynamic models are analyzed in which pheromone-baited trapping and food-baited trapping are
used simultaneously to eradicate an insect pest. The pest species is assumed to be under partial control by a host-specific
parasitoid species. The two models assume that density-dependent population regulation is accomplished either by host larval
competition or by means of oviposition interference among the parasitoids. The two trap types interact in a positive synergistic
manner and this combination appears to be very promising as a useful combination of pest control methods. Several features
of the system are examined; the feature which appears to cause the greatest problem is the possibility of the parasitoids
being attracted to the pheromone or the food traps. In either case, the degree of attraction does not have to be very great
to undermine the control effort. It is seen that food trapping becomes indispensible if host pheromone is used by the parasitoids
as a host-locating kairomone. If odor in the food traps is used by the parasitoids as kairomone, then the situation appears
more optimistic, as the reduction in efficiency of the food traps appears much less than with the pheromone traps when pheromone
acts as kairomone. 相似文献
2.
Hugh J. Barclay 《Researches on Population Ecology》1996,38(1):75-85
The development of resistance to insecticides is now widespread among insects. Other methods of pest control are also potentially
at risk of encountering resistance. A modelling approach is presented here to evaluate the effects of combining methods of
insect pest control on the selection for resistance to the control methods. This analysis is based on partitioning the total
mortality acting on a population into its constituent components from all known sources, and these are related to selection
for resistance. When two control methods are used in combination, selection for resistance against the two is a linear function
if the two don't interact, otherwise it may be sublinear or supralinear. A specific example is presented using a model of
the Olive fruit fly (Dacus oleae Gmel.) and employing food-baited and pheromone-baited traps for control. The control methods that appear least likely to
encounter resistance are natural enemies and the use of pheromone traps for male annihilation. These should be integrated
into a control program where possible to minimize the development of resistance to other control methods being used. 相似文献
3.
Hugh J. Barclay 《Researches on Population Ecology》1992,34(1):91-107
Summary An age-structured population model is used as a vehicle for presenting a method for the analysis of interactions between pairs
of insect pest control methods. This analysis is based on partitioning the total mortality acting on a population into its
constituent components from all known sources. Pairwise critical mortality curves are then constructed which represent the
combined mortality required for eradicating the pest population. Effort curves are then constructed from computing the mortality
resulting from a given amount of control effort. The convolution of the critical mortality curves and the effort curves then
yields the isoclines formed by the effort required of two control methods in combination to achieve eradication. This analysis
allows the prediction of either synergism or interference between the control methods and also helps explain patterns observed
in previous modelling of such combinations of pest control methods. 相似文献
4.
Summary To determine the effectiveness of a pest management system that uses pesticides at a low level, we censused populations of
seven insect pests and three plant diseases from 1980 to 1989 in a citrus orchard which was managed with a pesticide-reduced
and pesticide-free protocols, in Wakayama Prefecture, Japan. In the orchard, we controlled the pests solely by spraying petroleum
oil once a year from 1980 to 1985, by not spraying insecticide in 1986, and spraying only germicide in 1987. The arrowhead
scale population remained much lower level at which citrus trees begin to wither when petroleum oil was sprayed, whereas it
rapidly increased and began to wither trees during the years without spraying petroleum oil. The Indian wax scale population
rapidly increased only during a 2-year period and then declined. Although the infection level of the sooty mold was unusually
high on the trees where the density of the scale was high, this pathogen did little damage to citrus trees. The population
of the red wax scale gradually increased throughout the census period but did not reach the level at which citrus trees begin
to be damaged. Other pests also caused negligible damages to citrus trees. The results indicated that the pesticide-reduced
pest management system which was proposed by Inoue and Ohgushi (1976, 1977) is valid for the prevention of the outbreak of
the arrowhead scale, and that is has the sufficient control efficiency for the other pests in citrus orchards.
Contribution to the ecological studies of scale insect 3. 相似文献
5.
Models are presented to investigate the population dynamic behavior of a pest population with the release of pheromone for
mating disruption. Three mechanisms of mating disruption are considered: (i) confusion of males, (ii) competition with female
pheromone trails yielding false trail following, (iii) emigration of males prior to mating. In addition, several refinements
to confusion are considered. Confusion and emigration of males were found to be very similar both quantitatively and dynamically;
also, a combination of both mechanisms was very little more efficient than either one separately. False trail following is
difficult to compare with the other two, since competition with wild females is involved and thus the total population size
enters the equations. Density dependence of the action of pheromones results in some cases in which mating disruption cannot
control the pest population. Similarly, aggregation of the pest population decreases the efficiency of the method unless the
pheromone action is density independent. Delayed mating of females makes control easier, and may constitute one mechanism
for mating disruption. 相似文献
6.
Takashi Saitoh 《Researches on Population Ecology》1991,33(2):367-386
Summary The effects of breeding territoriality on the stability of grey red-backed vole (Clethrionomys rufocanus bedfordiae) populations were investigated on a control grid and a grid on which the voles were fed, in an outdoor enclosure in Hokkaido,
Japan. Vole populations were monitored by live trapping from 1984 to 1986: (1) Population density was 2–7 times greater on
the experimental grid to which food was added than on the control grid. Reproductive output was more closely associated with
the difference in density between grids than survival or dispersal (immigration and emigration) rates. (2) The number of adult
females and pregnancy rate of the experimental population were significantly greater than those of the control one. The difference
in the number of adult females between the populations was greater than that in pregnancy rate. (3) The proportion of successful
litters and the number of weanlings per litter were not significantly different between the control and experimental population.
(4) Adult females held territories on both the control and experimental grid; they were spaced out more than would be expected
from random occupation. The territories overlapped more on the experimental grid than on the control grid. (5) Mean territory
size of adult females on the experimental grid was about half of that on the control grid. The territory size was correlated
negatively with population density. (6) The proportion of trap sites that were used by adult females was significantly greater
on the experimental grid than on the control grid. This suggests that adult females on the experimental grid used the area
more extensively. This factor, in association with territory size and overlapping of territory, was also important in causing
the difference in the number of adult females between the grids. (7) These results call into question the hypothesis that
territoriality stabilizes the density in populations ofClethrionomys. 相似文献
7.
Yosiaki It? Masakazu Shiga Nobuhiko Oho Hitoshi Nakazawa 《Researches on Population Ecology》1977,19(1):33-50
Summary Based on the results of ecological surveys ofAdoxophyes orana and its natural enemies in apple orchards sprayed with the granulosis virus and control plots, we constructed working models
to simulate the population dynamics in three different experimental plots; those treated with chemical insecticides, those
with granulosis virus, and controls. The number of individuals killed by predators, parasitoids and by miscellaneous mortality
factors could be calculated on the assumption of imperfect density relations; that is, relation of the number killed by each
factor with the initial number of larvae was represented by a curve with an upper asymptote. We could estimate the proportion
of virus infection using curves with upper asymptotes. Rate of increase from pupa to middle instar larvae of the next generation
was subject to strong density-effect.
Simulation we proposed in this paper suggests a possibility that a single spray of the virus at 1st generation can reduce
not only the number ofA. orana larvae in the 2nd and 3rd generations but also the degree of fruits injured by this insect. Spray of chemical insecticide
is considered to be ineffective in reducing the pest density and the degree of injury to low levels in subsequent generations,
as compared with untreated plot, where the density of the 1st generation larvae is low. 相似文献
8.
A quantitative risk assessment is needed for each quarantine pest insect to ensure quarantine security without sacrificing
the transparency of international trade. The probability of introduction, which is defined as the probability that one or
more reproductive individuals of a pest insect species pass the port, is one of the basic components determining the risk
of pest invasion. The probability depends on two biological characteristics of pests: mode of reproduction and spatial distribution
of insects per host plant. In this article, the probability of introduction was calculated for each of the following four
categories: (1) bisexual, gregarious pests; (2) bisexual, solitary pests; (3) parthenogenetic, gregarious pests; and (4) parthenogenetic,
solitary pests. Then, equations were derived to predict the effects of two prevention practices conducted before export: disinfestation
treatment and the subsequent export sampling inspection of consignments. These equations also enable estimation of the probability
of introduction under natural mortality, which thus can be used in place of the criterion of Maximum Pest Limit (MPL). The
method was applied to the Mexican fruit fly Anastrepha ludens (Loew), as an example. The contour graph of the probability of introduction indicated the optimal combination of the intensity
of two prevention practices that ensures a given security level. Existence of an antagonistic interaction was also indicated
between the disinfestation treatment and the subsequent sampling inspection.
Received: January 22, 1999 / Accepted: September 6, 1999 相似文献
9.
Kazuo Nakamura Yosiaki It? Kazuyoshi Miyashita Akira Takai 《Researches on Population Ecology》1967,9(2):113-129
Summary The population parameters of green rice leafhopper,Nephotettix cincticeps in hibernated generation was estimated by the capture-recapture method on the gramineous weeds of resting paddy field from
late in April to mid-May, 1962–1965.
The difficulty of applying the capture-recapture method to this insect is caused from the low density and the low activity
of the leafhopper, so that it is necessary to make the suitable plan of capture-recapture series and to construct the special
method to detect the population parameters.
The number of adults differed greatly among the years and among the plots in the same year. But, in general, the density was
relatively high late in April, and decreased rapidly in May. The number of males was higher than that of females late in April,
but decreased rapidly to become lower in May.
The sampling efficiency with sweep-net depends upon the many factors, such as weather and floristic conditions; especially
the atmospheric temperature and the force of wind are considered to affect greatly to the efficiency. In general, low temperature
and strong wind are the cause of low sampling efficiency.
Contribution from JIBP-PT No. 20. 相似文献
10.
I Nyoman Widiarta Yoshito Suzuki Hiroichi Sawada Fusao Nakasuji 《Researches on Population Ecology》1990,32(2):319-328
Summary The population dynamics ofNephotettix virescens, a vector of rice tungro virus disease was investigated in a synchronized transplanting area at Jatisari (1984–1986), West
Java and in a staggered transplanting area at Sidan (1986–1988), Bali, Indonesia. The FARMCOP suction sampler was employed
for population censuses ofN. virescens and its natural enemies. The population growth pattern was affected by transplanting pattern: In the staggered transplanting
area, the population density increased from the immigrant generation to the first generation, and sharply decrease thereafter,
while in the synchronized transplanting area the population density often reached the highest peak in the second generation.
The degree of contageousness in the spatial distribution ofN. virescens was negatively correlated with population density of the immigrant generation.
Contribution from Indonesia-Japan Joint Program on Food Crop Protection 相似文献
11.
Silvana Amaral André Augusto Gavlak Maria Isabel Sobral Escada Ant?nio Miguel Vieira Monteiro 《Population and environment》2012,34(1):142-170
This work proposes a methodological approach to redistribute population data obtained from polygonal census tracts into population density surfaces (grids) based on a cell space database. The methodology was first developed for the municipality of Marabá, Pará state, in the Brazilian Amazon. We used a dasymetric method to eliminate areas of environmental restriction to human presence; then integrated environmental data indicative of human presence to generate a potential surface of population occurrence; and finally, census population count data were redistributed into cells. The methodology was subsequently adapted for 13 municipalities of the Sustainable Forests District (SFD) of BR-163, generating population distribution surfaces for 2000 and 2007. The evolution of the resident population over the SFD-BR163 showed spatial patterns compatible with the occupation process described in the literature and verified by fieldwork. To be applied over other areas, the proposed methodology must be adapted with local parameters but in this way, population density surfaces can be useful as an additional data source to study population and environment relationships. 相似文献
12.
T. S. Bellows Jr. M. Ortiz J. C. Owens E. W. Huddleston 《Researches on Population Ecology》1982,24(1):142-156
Summary A model is developed for the analysis of insect stage-frequency data which may be applied to populations with age-dependent
mortality. The analysis of stage-frequency data is divided into two steps. In the first step, the number of different mortality
rates and their values are estimated. The second step provides estimates of developmental rates and variances for each developmental
stage and in addition provides estimates of the number of recruits to each stage. The model may be used both in analysis and
prediction of insect stage frequencies. Hence, in addition to estimating developmental and mortality rates from stage-frequency
data, it may also be used as a simulation model for an insect population. The model is applied to two populations ofHemileuca oliviae
Cockerell, a lepidopterous pest of New Mexico grasslands. The model identifies, in the two populations, different mortality rates that
are related to plant productivity. 相似文献
13.
Midori Tuda 《Researches on Population Ecology》1998,40(3):293-299
In an insect host (the cowpea weevilCallosobruchus maculatus)- parasitoidHeterospilus prosopidis) experimental system, the population densities of the component species oscillated for the first 20 generations and then
abruptly stabilized as the parasitoid density decreased. Examination of the host and parasitoid after the 40th generation
in the long-term experiment showed that (1) host larvae exhibited contest-type competition (killing other larvae inhabiting
the same bean), in contrast to the founder population being scramble-type competitors and (2) the parasitoid attack rate on
the host did not change. There was also an evolutionary trade-off between body size and the rates of larval survival and development,
suggesting a cost of contest competition on larval survivorship and development. I tested model predictions (Tuda and Iwasa
1998) that (1) host equilibrium population size should gradually decrease as the proportion of the contest type increases
and that (2) random attacks of the parasitoid on the host should reduce the rate of increase in proportion of the contest
type, and the effect should become manifest especially during the first 20 generations. Two of three host-only replicates
showed significant decrease in population sizes. Although the density of emerging adults per bean did not differ between replicates
of the host-only and host-parasitoid systems, comparison of the host body size between them on day 270 (at the 13th generation)
showed that the host was more contest-type in the host-only system than in the host-parasitoid system, as the model predicted,
and later on day 650 the effect of the parasitoid had disappeared. 相似文献
14.
The outbreak mechanisms of the green rice leafhopper,Nephotettix cincticeps Uhler, in northern Japan
Intraspecific regulatory processes keep the population ofNephotettix cincticeps stable at a low density in southern Japan. In northern Japan, however, the yearly population density of the insect fluctuates
violently, and large outbreaks occasionally take place. To clarify the difference in the population dynamics between the two
regions, we analyzed light-trap and sweep-net sampling records from prefectural and national agricultural experimental stations.
The survival rate of the overwintering population decreased with increases in the period of continuous snow cover (PCSC) in
the north, and initial population densities in the years of long PCSC were too low for populations to reach equilibrium density
by the end of the active breeding season. This made yearly population fluctuations in the north much larger than in the south.
The equilibrium density in the north was higher than in the south. The higher equilibrium density presumably permits the higher
population density and larger yearly population fluctuations in the north. A major factor responsible for the difference in
equilibrium densities between the two regions is the difference in heading dates of the host plant (rice). Qualitative differences
among rice plant varieties, and among biotypes ofN. cincticeps, may also be important. 相似文献
15.
Summary An age-structured population dynamics model is presented that incorporates pheromone-trapping and food-trapping as control
methods for an insect pest. The model yields the following results. Low rates of pest survivorship allow lower trapping rates
for control. Species with long developmental periods are easier to control than those with shorter developmental periods (other
factors being equal) due to lower net survival. The rates of pheromone trapping alone for effective control are usually very
high. The combination of pheromone and food trapping allows control with much lower trapping rates than either method alone.
Even small amounts of immigration of adult pests into the control area renders pheromone control ineffective, whereas food
traps suppress both the immigrants and the resident population. Food- (or odor-) baited traps which attract both males and
females are only somewhat more efficient than those which attract females alone. The existence of density-dependent population
regulation assists the control program substantially, but this assistance declines as food trapping becomes a more important
part of the control program. Larval competition strongly affects the required trapping rates for eradication; species in which
all larvae exert strong competition are much easier to control than those in whic the younger larvae contribute little to
the total competitive depression. 相似文献
16.
Kenji Fujisaki 《Researches on Population Ecology》1985,27(1):125-136
Summary The wing polymorphism of the oriental chinch bug,Cavelerius saccharivorus, was studied in relation to its reproductive strategy. The frequency distribution of wing form in terms of the relative wing
length (R.W.L.) changed with increase in the population density from a single modality biased toward the brachypterous form
to bimodality with both macropterous and more extreme brachypterous forms. Since some evidences in the field showed that fliers
are limited to macropters, such a bimodality of wing form indicated thatC. saccharivorus employs a mixed strategy with some portion of adults staying on in the same habitat, whereas the rest disperse. Moreover,
macropters were larger in body size than brachypters emerging in high density populations, although smaller than brachypters
emerging in low density populations. Larger body size as well as the delay of ovarian maturation in macropters was considered
to be a beneficial trait for migratory behaviour. 相似文献
17.
Masakazu Shimada 《Researches on Population Ecology》1999,41(1):69-79
Population dynamics and variability were examined in one-host–two-parasitoid experimental systems with different resource
distributions: resource-clumped and resource-sparse conditions. The system consists of a seed beetle host, Callosobruchus chinensis, and two parasitoid wasps, Anisopteromalus calandrae (Pteromalidae) and Heterospilus prosopidis (Braconidae). In the resource-clumped condition, suitable hosts for parasitism (the late fourth-instar larvae and pupae)
were clumped in 1 large resource patch, but they were scattered evenly among 16 small patches in the resource-sparse condition.
Population censuses were conducted at 10-day intervals in long-term cultures, renewing 10 g of azuki beans (Vigna angularis). In both resource conditions, the first period was a single-species system of C. chinensis only, and A. calandrae was added in the second period. The one-host–one-parasitoid system with C. chinensis and A. calandrae showed stable population dynamics with small fluctuations. After addition of H. prosopidis in the third period, two of three replicates persisted to day 800 in each resource condition, although one replicate in each
went to extinction at an immediate outbreak of the H. prosopidis population after the introduction. Population variabilities of C. chinensis and H. prosopidis were significantly higher and the mean population size of A. calandrae was significantly smaller in the resource-sparse condition than that in the resource-clumped one. A short-term experiment
on parasitism efficiencies revealed that H. prosopidis parasitized significantly more at a low host density in the resource-sparse condition than in the resource-clumped one. Mutual
interference of H. prosopidis was weak enough at low parasitoid densities but became abruptly stronger with high densities. Providing fresh hosts in a
mixture of already parasitized ones, host-searching behaviors of a parasitoid were recorded by video for 3 h and were compared
between the two wasp species. H. prosopidis could parasitize fresh hosts more efficiently than A. calandrae through frequent long-distance walks (walking to distant beans at one bout or outside a clump of beans with hosts and back
soon on a distant bean of the clump) after reencounters with parasitized hosts. Considering all the experimental results,
populations were judged to be more fragile and more likely to go to extinction in the resource-sparse condition than in the
resource-clumped one. A higher attacking efficiency of H. prosopidis destabilized population dynamics more in the resource-sparse condition.
Received: December 23, 1998 / Accepted: January 20, 1999 相似文献
18.
Edward Gross 《Population studies》2013,67(2):113-120
U.S. Census data are used to show that, as the density of a metropolis increases there is a concomitant increase in the movement of population to the suburbs. This relationship is closest for small metropolitan areas. As size of the area increases, the closeness of the relationship decreases until it reverses—the largest areas actually show a slight decline in metropolitanization when density goes up. It is concluded that metropolitan expansion has definite bounds set by technological factors which place a limit on the distance that the commuter can reasonably travel daily. For cities with populations of less than 500,000 there is a correlation of near zero between size of population and density. Such cities therefore maintain a constant density. But for cities with larger populations, size of population and density rise together. It is concluded that small cities undergo metropolitan expansion with ease. Distances are within technological limits and any increase in population is reflected in an increase in area. But when a certain area is reached, further expansion is curtailed with a resultant increase in internal density. The net result is a stopping or slowing down of the metropolitan process. 相似文献
19.
Keiji Kanamitsu 《Researches on Population Ecology》1965,7(1):16-22
Summary A field population ofEvetria cristata was studied in 10 plots in 1962 and in 6 plots in 1963. These plots were divided into 2 or 3 groups of different population
levels of the shoot moth in respective years. The survival of the insect was then analysed in these different groups of plots.
The survival rate ofE. cristata from eggs to adults in the first generation was found always higher in the group with low population density, which indicates
the existence of some factors that affect the population more severely when the insect is more abundant.Lissonota evetriae andPediobius sp. seemed to have killed more proportion of the hosts where the shoot moth density was high. However, the total effect of
the all natural enemies was not always great in the plots with high density of the moth. The survival of the second generation
of the moth in 1963 was observed to be much higher at any population level than in the other generations. 相似文献
20.
Tadashi Miyashita 《Researches on Population Ecology》1992,34(1):143-153
Summary Field studies were conducted to clarify whether variation in food availability among habitats influences population density,
and whether population density has a negative effect on foraging success in the orb-web spider,Nephila clavata.
Lifetime food consumption per individual (i.e., foraging success) strongly correlated with mean body size of adult females
and mean fecundity in populations. Also, there was a positive correlation between foraging success and population density.
Since foraging success reflected potential prey availability in the habitat, food resource appeared to be a limiting factor
for populations in this spider. Mean fecundity per individual correlated with population density of the following year, suggesting
that decreased reproduction is a major component of food limitation on population density. Consistent defferences in mean
body size between particular sites were observed over years, while such difference was less obvious in density. Thus, ranking
of food abundance among habitats seems to be predictable between years. A field experiment revealed that an artificial increase
in population density had no negative effect on the feeding rate of individuals, suggesting that intraspecific competition
for food is not important in this species. 相似文献