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1.
Somchai Isichaikul Koichi Fujimura Toshihide Ichikawa 《Researches on Population Ecology》1994,36(1):23-28
Nymphs ofNilaparvata lugens were experimentally reared from the 2nd instar in a cage covering part of the leaf sheath of an individual rice plant grown
in a Wagner pot. Plants were covered with the cage from the water surface of the pot to 10 cm above the surface (lower cage-group)
or from 10 cm to 20 cm above the surface (upper cage-group). Temperatures measured at three different parts of the cage remained
fairly constant in both groups at around 25°C (23.7–25.2°C in mean value). In the lower cage-group, relative humidities measured
at the three heights in the cage in (76.3–90.5% in mean value) markedly increased with the approach to the water surface.
The nymphs of this group, particularly during the molting period, aggregated close to the surface. Eighty-two percent of the
released nymphs emerged in this group. Relative humidities measured at three heights of the upper cage-group were 69.5–72.7%
in mean value, and all the nymphs in this group died within 3 days after their release although half of them stayed on the
rice plants within 6 h after their release. The role of relative humidity as a limiting factor on the range of the microhabitat
and the population density ofN. lugens in rice fields was discussed on the basis of the results. 相似文献
2.
The effects of distance between hatching larvae on survival and development were investigated inMonochamus alternatus. Two newly-hatched larvae were inoculated intoPinus densiflora bolts at a distance of 2.5 cm or 10 cm, simultaneously or at an interval of 2 weeks. Some larvae were inoculated singly as
a control. When larvae were inoculated simultaneously, mortality of the closely-inoculated larvae was significantly higher
than that of distantly-inoculated larvae. Such high mortality was identified as due to conspecific bites. When the two larvae
were inoculated asynchronously, the first-inoculated larvae killed some second-inoculated larvae but were never killed by
them. Consequently, mortality was higher in second-inoculated larvae than in first-inoculated larvae. In particular, there
was a significant difference in mortality between them when the larvae had been inoculated closely. The mortality of second-inoculated
larvae was higher in the closely-inoculated group than in the distantly-inoculated group although there was no significant
difference between them. In the case of two simultaneously-inoculated larvae, the initial distance between them had no significant
effect on the development and growth in the early larval stage. When the larvae were inoculated asynchronously, the first-inoculated
larvae grew more quickly than singly-inoculated control larvae. 相似文献
3.
Katsumi Togashi 《Researches on Population Ecology》1990,32(1):1-13
Summary Newly-emerged adults ofMonochamus alternatus aged 1 to 5 days were code-numbered with lacquer paint and released by placing them on the trunks of one or two trees in
aPinus thunbergii stand at weekly intervals during the beetle emergence period from 1980 to 1983. Beetles were captured at weekly intervals
from one week after the first day of release. Determinations were made on the distance and direction of beetle dispersal during
a week after release and analysed by a method of Inoue (1978). When the stand canopy was closed, the rate of beetle’s stay
on trees was 0.56 per week. The beetles dispersed at random by walk and flight. When the pine stand was sparse, the rate of
beetle’s stay on trees was 0.02–0.30 per week. They dispersed at random by flight. The average distances traversed were estimated
to be 7.1–37.8 m for the first week after emergence. Using other method, the average distance traversed was estimated to be
10–20 m for each week through the first 3 weeks after release. The results of stepwise multiple regression analysis and a
simple field experiment suggested that the dispersal of newly-emerged beetles was affected by stand density, number of beetles
emerging from individual dead trees, maximum air temperature, and precipitation. 相似文献
4.
Summary Seasonal changes in the percentage of macropterous individuals in natural population ofMicrovelia douglasi in permanent habitats were investigated in Shimane, western part of Japan. Macropterous forms of 5th instar nymphs occurred
most frequently from late June to early July. However, the seasonal appearance of macropterous adults differed between habitats
and years. There were significant effects of density, temperature, photoperiod and food availability on the percentage of
macropters under laboratory conditions. The percentage of macropterous forms generally increased with density, but the mode
of the response was modified by temperature, photoperiod and food availability. When insects were reared under long day photperiod
(16L8D) with abundant food (0.5–1.0 g/container/day), the percentage of macroptery varied most among the different density
treatments at the intermediate temperature (24°C) and the difference was reduced at higher temperature (28° and 32°C). Effects
of temperature were small under the short day photoperiod (12L12D). Under 12L12D photoperiod sensitivity of density responses
were higher at 32°C and lower at 24°C than those under 15L8D photoperiod. When the insects were supplied with food every other
day, the density response became obscure. Ecological significance of environmental responses in the wing morph determination
was discussed in relation to the heterogeneous environment of water surface. 相似文献
5.
Summary The biology of the veliid bugM. d. atrolineata, its predatory behavior, and the effects of plural hunting were studied to evaluate its role as a predator of the brown planthopperNilaparvata lugens in the Philippines. The probability of planthoppers falling onto the water surface and provision of habitat continuity was
measured by a sticky trap placed at the base of rice hills in a greenhouse and in paddy fields.
The developmental period of immature stages combined was 21 days. If given prey, females laid 25 eggs on the average during
an adult life span of 18 days. Starved adults could survive for only 3–5 days.
The functional response to prey density was sigmoid, and the maximum number of prey killed was 7 per day. Prey feeding was
completed in 12–36 min. The percentage of successful prey attacks averaged 5–8%, decreasing with higher (and larger) developmental.
stages of prey, but adult prey were found the soonest. Plural hunting increased the probability of capturing prey by as much
as 2.5 times that by individual hunting.
Late-instar nymphs, which may be more active, fell from rice hills in a greenhouse more than early-instar nymphs, and the
number falling increased with density. In the field the percentage of planthoppers falling to the water in 1 day varied considerably,
from 1% for nymphs in one field to 67% for adults in another field.
On the basis of work described above and given the high density of veliid predators in flooded paddy fields of tropical Asia,M. d. atrolineata is considered one of the most important natural enemies of the brown planthopper. 相似文献
6.
Summary Effects of starvation on the suryival period and the respiratory rate in adults of a wolf spider,Pardosa astrigera (L. Koch), were investigated. The spiders used were divided into four groups: well-fed, starved and two limited food groups; in the
latter two, each spider was supplied with one leafhopper every second or third day. Adult males and females ofP. astrigera could survive for a long time; 28.8±2.7 days and 54.4±18.9 days, respectively, without any food. The longevities shown here
were 73.8% for males and 78.6% for females of those of well-fed spiders, indicating thatP. astrigera adults have a strong tolerance to starvation. The respiratory rate of well-fed adults showed no tendency to increase or decrease
with their aging; the mean respiratory rates were 4.86×10−4 mg CO2/mg f.w. (fresh body weight)/hr for males and 3.80×10−4 mg CO2/mg f.w./hr for females. The respiratory rates of starved spiders increased during the first two days of starvation but decreased
markedly from the third to the twelfth day, and thereafter retained an almost constant level for each sex. The mean respiratory
rates after the twelfth day of starvation were 2.49×10−4 mg CO2/mg f.w./hr for males and 2.76×10−4 mg CO2/mg f.w./hr for females; these values were respectively 48.4% and 63.0% of those prior to starvation. The fresh body weight
of starved spiders decreased linearly with time but the rate was small. The respiratory rates of the limited food groups tended
to decline with time and thereby their weight losses were minimized. The decrease in the respiratory rate under starvation
was considered not to be due to spider exhaustion or senescence but due to an intrinsic change in behaviour and/or metabolism,
because when the spiders were supplied with ample food for five days after starvation, the respiratory rate and the body weight
rapidly recovered to near the levels prior to starvation. It is suggested that starved spiders use a higher ratio of fat as
catabolic substrate than normally fed or satiated ones. Feeding strategies of poikilo-therm predators are discussed.
This work was partially supported by the Nippon Life Insurance Foundation Research Fund and Grant-in-Aid (No. 56480039) from
the Ministry of Education, Science and Culture, Japan. 相似文献
7.
Yoshinari Tanaka 《Researches on Population Ecology》1990,32(2):329-335
Summary Age-specific effects of inbreeding on fecundity were assayed for adzuki bean weevilCallosobruchus chinensis by comparing inbred lines and their cross. Four consecutive full-sib matings reduced only 10.3 percent in total fecundity,
and did not decrease early fecundity at all until third day from the onset of reproduction. It is suggested that recessive
detrimental genes have been eliminated from the early period of adult life span when reproductive value is high. There was
a slight tendency that inbreeding depression increased as age proceeded though not statistically significant. 相似文献
8.
Yosiaki It? 《Researches on Population Ecology》1964,6(1):13-21
Summary To elucidate the basic food requirement of spiders, the important polyphagous predators of rice-plant insect pests, an attempt
was made to measure the respiratory energy loss of fasting spiders,Lycosa pseudoannulata.
Relationship between fresh (y) and dry (x) weights of spiders inhabiting the bottom layer of the rice-plant community was represented by the following allometric equation:y=0.428x
0.872.
The carbon dioxide production by previously fed and unfed females under the dark at 29°C 100% R. H. was measured by a titration
technique. The relationship between fresh body weight and CO2 production by unfed animals could be represented by the equationM=aW
b, M being the CO2 output per individual per day andW the fresh body weight. The constantb, which determines the slope of curve, was 0.808. Respiration of the adult female with 100 mg fresh weight was 1.155±0.250
mg CO2/100 g fresh weight/day or 48.69 mg CO2/g dry weight/day. This value corresponds to 35.81 cal/g fresh weight/day or 150.94 cal/g dry weight/day. Supposing the calorific
content of spiders to be 5820 cal/g dry weight, rate of the respiratory energy loss to total energy of the body was estimated
to be 2.60%. This rate did not strongly contradict with the loss of fresh body weight before and after the measurement.
The metabolic rate showed remarkable fluctuation with changing food supply. The CO2 production of starved individuals decreased to 83.63±16.34% as compared with individuals which were fed before the measurement. 相似文献
9.
Masami Hasegawa 《Researches on Population Ecology》1990,32(1):119-133
Summary The demography of the lizardEumeces okadae was studied for 4 years on Miyake-jima, in the Izu Islands, central Japan. Most males matured at 3 years of age with a mean
snout-vent length of 77.5 mm. Females matured at 3–4 years with a mean SVL of 77.8 mm, and reproduced biennially thereafter.
Growth continued after maturity with a decreasing rate. In females, annual growth was negligible in reproductive years, but
resumed markedly in non-reproductive years. Clutch size increased with SVL and was used to construct a fecundity schedule.
Population density (exclusive of hatchlings) was estimated to be ca. 4000 individuals/ha in August, an exceptionally high
density for lizards. Before introduction of the weasel onto Miyake-jima, low predation pressure had allowedE. okadae to maintain a high population density. Estimated annual survival rates were 36% for hatchlings, 56% for yearlings, 80% for
2-year-olds, 63% for adult males and 76% for adult females. The cohort generation time (6.95 years) was so long that theE. okadae population can be characterized by a combination of low natality and slow turnover. 相似文献
10.
Yasuyuki Sirota 《Researches on Population Ecology》1978,19(2):170-180
Summary Experiments for analyzing the movement and dispersal of larvae ofC. pipiens molestus were made and preliminaly simulation models were constructed. The models were based on two distributions, the distance and
direction of movements between 1 minute intervals. The distribution of distance is represented by a unimodal curve, and that
of angle by a bimodal one. The results of simulation reasonably depicted the actual process of movements. Nevertheless, the
simulated time-dispersal curves overestimated the number of dispersed individuals. This might be due to mutual attraction
among the larvae.
Contribution No. 68 from the Lab. of Entomol. Fac. Agric. Hirosaki Univ. 相似文献
11.
Summary Two species of tortoise beetles,Aspidomorpha miliaris (AM) andA. sanctaecrucis (AS) feeding on a shrub-like morning glory,Ipomoea carnea, were reared under laboratory conditions to study their survivorship and fertility schedules. AM and AS required 34–39 days
and 30–37, respectively, for the development of the immature stages. The mean longevity of the males was 88.4 days in AM and
63.8 in AS, and that of females was 87.9 days in AM and 83.3 in AS. The mean length of the pre-reproductive period (27.2 days
in AM and 33.8 in AS) was much longer than that of the post-reproductive period (10.9 days in AM and 14.3 in AS). Females
laid eggs at a nearly constant rate throughout their reproductive period. The reproductive valueV
x
/V
0
of the two species remained high for most of their adult life, as a result of prolonged survivorship and fertility periods.
The total number of eggs produced per female was 442.9 (AM) and 80.1 (AS). The intrinsic rate of natural increaser was 0.070 (AM) and 0.044 (AS) per capita per day. The prolonged reproductive schedules, coupled with strong dispersal power,
of these species no doubt have an adaptive value for living in highly disturbed tropical environments, where rainfall is ample
but unpredictable and food resources are available throughout the year in a wide area, but distributed in widely flung patches.
Contributions to the knowledge of population dynamics of tortoise beetles in Sumatra 3.
Contribution No. 33 of Sumatra Nature Study (Entomology).
Partly supported by Grants from Japan Society for Promotion of Science for JSPS-DGHE Scientific Cooperation (1980, 1982) and
Grants-in-Aid for Overseas Scientific Survey from Ministry of Education, Science and Culture of Japan (Nos. 56041027 and 58041030). 相似文献
12.
Pierre-Alexandre Landry Fran?ois-Joseph Lapointe 《Researches on Population Ecology》1999,41(3):263-268
A survey of the genetic variability in deer mouse populations was performed using specimens collected from six different
islands on a lake covering approximately 50 km2. Random amplified polymorphic DNA (RAPD) was used to measure the extent of the genetic differences in this insular system.
An analysis of molecular variance (AMOVA) revealed that populations are clearly separated at this microgeographic scale (F
st
= 0.13863; P < 0.001). The homogeneity of molecular variance test (HOMOVA) indicated that within-population levels vary greatly (B
p
= 0.76831; P < 0.001). The within-population molecular variance was found to be mainly correlated with the accessibility of the islands,
computed as the inverse of the geographic distance separating an island from the lakeshore (r = 0.916; P < 0.003).
Received: March 5, 1999 / Accepted: July 16, 1999 相似文献
13.
Tomoji Endo 《Researches on Population Ecology》1988,30(1):107-121
Summary The pattern of prey utilization of the orb-weaving spiderAraneus pinguis was studies by comparing between arthropods restrained in the empty webs (spiders were removed) and those unattacked in the
intact webs (spiders were not removed). The number of arthropods was larger in the empty webs than in the intact webs. In
the empty webs, web area, mesh width, number of radii, and signal thread length were presumed to affect the number of arthropods
left in a single web. As for the intact webs, web area, mesh width, and web-exposure time were important factors. In the empty
webs, the density of arthropods decreased away from the hub. On the other hand, the density of unattacked arthropods in the
intact webs was the same throughout the web.
Arthropods in the empty webs were larger than those in the intact webs. The upper limit in size of unattacked arthropods increased
along with the distance from the hub in the intact webs, but not in the empty webs. These results indicate increase in the
minimum size of eaten arthropods increased in the former. This positive sizedistance relation may have resulted from the adaptive
switching of spiders’ alternative foraging methods (i.e., the rapid attack at encounter and the later eating during web deconstruction)
on the basis of the prey profitability. 相似文献
14.
Preference and performance linkage in aPhyllocolpa sawfly on the willow,Salix miyabeana, on Hokkaido
A leaf-folding sawfly in the genusPhyllocolpa (Hymenoptera: Tenthredinidae) attackingSalix miyabeana (Salicaceae) was studied near Sapporo, Hokkaido, along the Ishikari River in 1993. Host plant individuals were young trees
4–7 years old which were growing rapidly, producing some long shoots with large leaves. On a gradient of shoot length classes
from 0–5 cm long to over 80 cm long, shoots were much more abundant in the shorter shoot length classes. However, attacks
by ovipositing females increased as shoot length increase from 0 attacks on the shortest shoots to 5.17 attacks per shoot
on the longest shoots. The frequency of attack per leaf increased from 0 to 0.13 over the same range of shoot lengths. This
pattern of attack resulted in a high frequency of larval establishment in feeding sites, between 0.96 and 1.00, in all attacked
shoot length categories. However, probability of survival to a late instar larva increased with shoot length and corresponded
to the attack pattern, indicating a preference-performance linkage between female ovipositional decisions and larval survival.
The patterns found for thisPhyllocolpa species are similar for galling sawflies in North America and Europe, especially in the genusEuura, members of which make stem, bud and leaf midrib galls. Extending the pattern to aPhyllocolpa species broadens identification of pattern and ultimately the generality of the emerging theory on populations of galling
sawflies. 相似文献
15.
Makoto Kat? 《Researches on Population Ecology》1984,26(1):84-96
Summary The mining pattern of the honeysuckle leaf-minerPhytomyza lonicerae which feeds onLonicera gracilipes was analyzed with special reference to the avoidance of parasitoids' attacks. The leaf-miner makes the linear mine with branches
and crosses by turning and branching, off the backtracking mine. Both average numbers of turnings and branchings were about
4. The speed of mining was 1.5 times faster in backtracking than in advancing. The mine width increased as the mining larva
grew and total volume of consumed plant tissue was nearly constant independent of variability of the number of turnings and
other characteristics of the mine. The majority of larval mortality were due to attacks by parasitoid wasps (Chrysochairs pentheus andDiglyphus minoeus), which locate the present position of leaf-miners, by tracing mine tracks, and wasps attack leaf-miners at a higher rate
in backtracking than in advancing. The adaptive significance of branching and crossing by leaf-miners was discussed in terms
of the reduction of parasitoids' attacks. 相似文献
16.
Dockray S Grant N Stone AA Kahneman D Wardle J Steptoe A 《Social indicators research》2010,99(2):269-283
Measurement of affective states in everyday life is of fundamental importance in many types of quality of life, health, and
psychological research. Ecological momentary assessment (EMA) is the recognized method of choice, but the respondent burden
can be high. The day reconstruction method (DRM) was developed by Kahneman and colleagues (Science, 2004, 306, 1776–1780) to assess affect, activities and time use in everyday life. We sought to validate DRM affect ratings by comparison
with contemporaneous EMA ratings in a sample of 94 working women monitored over work and leisure days. Six EMA ratings of
happiness, tiredness, stress, and anger/frustration were obtained over each 24 h period, and were compared with DRM ratings
for the same hour, recorded retrospectively at the end of the day. Similar profiles of affect intensity were recorded with
the two techniques. The between-person correlations adjusted for attenuation ranged from 0.58 (stress, working day) to 0.90
(happiness, leisure day). The strength of associations was not related to age, educational attainment, or depressed mood.
We conclude that the DRM provides reasonably reliable estimates both of the intensity of affect and variations in affect over
the day, so is a valuable instrument for the measurement of everyday experience in health and social research. 相似文献
17.
Summary Intra- and interspecific competition between laboratory populations of four green leafhoppers,Nephotettix spp. was studied in the laboratory under three different temperature regimes of 24°C, 27°C and 30°C. For the single-species
population of the three tropical species, the equilibrium density increased as the temperature increased. On the other hand,
for the temperature speciesN. cincticeps, the highest equilibrium density was at the intermediate temperature and the lowest at high temperature.
Interspecific interactions between two tropical (N. virescens vs.N. nigropictus), a tropical and a temperature (N. virescens vs.N. cincticeps) and a rice-feeding and a grass-inhabiting (N. virescens vs.N. malayanus) Nephotettix species were also studied in the laboratory at the three temperature regimes. Temperature differentially affected the outcome
of competition between twoNephotettix species. BetweenN. virescens andN. nigropictus, the latter was more successful over the former at low and intermediate temperatures, while the former was more successful
at high temperature. BetweenN. virescens andN. cincticeps, the temperate species inhibited the growth of the tropical species at low temperature while the tropical species inhibited
the growth of the temperate species at high temperature. At intermediate temperature, the population ofN. virescens persisted at a slightly higher density over the population ofN. cincticeps. Between the rice-feedingN. virescens and the grass-inhabitingN. malayanus, regardless of temperature the population density of the latter was greatly reduced and later became extinct while the population
of the former continued its growth. These consequences of competition between twoNephotettix species conformed fairly well to those predicted by theLotka-Volterra model using demographic parameters specified for each species. 相似文献
18.
Juliann Saquib Abby C. King Cynthia M. Castro Lesley F. Tinker Stacy Sims James M. Shikany 《Journal of women & aging》2013,25(5):454-462
ABSTRACTTelephone-based interactive voice response (IVR) systems could be an effective tool for promotion of physical activity among older women. To test IVR feasibility, we enrolled 30 older women in a 10-week physical activity intervention designed around National Institute on Aging (NIA) Go4Life® educational materials with IVR coaching. Participants (mean age = 76 years) significantly increased physical activity by a mean 79 ± 116 (SD) minutes/week (p < .001). Participants reported that the Go4Life® materials, pedometer, and IVR coaching (70% reported easy technology) were useful tools for change. This pilot study demonstrates IVR acceptability as an evidence-based physical activity program for older women. 相似文献
19.
Summary We studied the relationship between the diurnal nectar secretion pattern of flowers ofCayratia japonica and insect visiting patterns to these flowers. Flower morphology ofC. japonica changed greatly for about 12 hours after flower-opening and the maximum duration of nectar secretion was 2 days. The nectar
volume peaked at 11∶00 and 15∶00, and declined at night and at 13∶00 regardless of time elapsed after flower-opening. The
nectar volume at the two peaks was, on average, 0.25 μl on bagged inflorescences and 0.1μl on unbagged inflorescences (both,
sugar concentration=60%). The flower secreted nectar compensatory when the nectar was removed. This means that insects consume
more nectar than the difference of nectar volume between bagged and unbagged flowers.
Apis cerana is a primary visitor of this flower, and was the only species for which we confirmed pollen on the body, among many species
of flower visiting insects to this flower.Apis cerana visited intensively at the two peaks of nectar secretion. Visits of the other insects were rather constant or intensive only
when there was no nectar secretion. Thus flowers ofC. japonica with morphologically unprotected nectaries may increase likelihood that their nectar is used by certain pollinators, by controlling
the nectar secretion time in day. In this study the pattern of nectar secretion allowedA. cerana maximum harvest of nectar.
Contribution to the ecological and bioeconomoical studies of the pollinator community in Kyoto I. 相似文献
20.
Tuyosi Sugimoto 《Researches on Population Ecology》1978,19(2):197-208
Summary The present paper studies how the female parasite ofKratochviliana sp. visits and attacks its host larvae of Ranunculus leaf mining fly,P. ranunculi at a single leaf visit. The parasite visited its hosts at random on the leaf. The frequency of host visits was independent
of the host density and the proportion of hosts survived from the parasite attack, in a leaf and its distribution was expressed
as a single straight line. It almost always attacked living hosts at the first host visit after isolated from them for one
day but with the rate of about 0.5 at the subsequent visits. In consequence, the relationships of the number of host attacks
and killed hosts to the host density drew satulated curves in each. A model of host attack by this parasite at its single
leaf visit was formulated by modifyingBakker
et al.'s model (1972) basing upon these observations and the attack avoidance by the parasite to already attacked hosts previously
reported.
Ecological studies on the relationship between Ranunculus leaf mining fly,Phytomyza ranunculi
Schrank (Diptera; Agromyzidae) and its parasite,Kratochviliana sp. (Hymenoptera; Eulophidae) from the viewpoint of spatial structure II.
This paper constitutes a part of the Doctoral Thesis presented to the College of Agriculture, Kyoto University by the present
author. 相似文献