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1.
Synchrony between development of five corn hybrid varieties of various seasonal growing rates (FAO numbers), seasonal flight
pattern of male cotton bollworm, Helicoverpa armigera Hb. (Lepidoptera: Noctuidae), as monitored by pheromone traps, and the subsequent appearance of newly hatched larvae on developing
cobs were studied at Mezőhegyes, South-Hungary, in 2003 and 2004. The phenological stages of corn hybrids were evaluated using
the Iowa State University Scale (R1–R5), the flight of male moths was monitored by large capacity, funnel type of pheromone traps and the appearance of freshly
hatched larvae on developing cobs were counted by visual inspection. The synchrony between the flight peak of male moths and
the peak apperance of L1 larvae on cobs was investigated by cross-correlation. In 2003 (average daily temperatures 20.7°C, average daily relative
humidity 59.9% for the period of 4–18 July) “DK 391”, “DK 443” and “Maraton” hybrid varieties already reached silking stage
(R1) by the time when pheromone traps indicated a peak, at 7 July (peak capture at 3-day intervals 755.5 males/traps). The number
of L1 larvae peaked on developing cobs of these varieties also at 7 July (7.0, 4.0 and 3.8 larvae/50 cobs, respectively). The synchrony
between the flight peak of male moths and the peak appearance of L1 larvae on cobs was proven (LAG = 0). A rather similar trend was observed in “Vilma” hybrid variety: it reached R1 stage at 7 July, and L1 larvae appeared only a few days later (11 July, 3.8 larvae/50 cobs) (LAG = −1). However, “Maxima” hybrid variety reached
R1 stage 1 week later (14 July) than the time of peak captures. Here L1 larvae peaked as late as at 18 July (0.8 larvae/50 cobs), i.e., only after the cob had reached R1 stage (LAG = −3). A reverse order of dates of R1 stage and peak capture was observed in “Maxima” in 2004 (average daily temperatures; 22.5°C, average daily relative humidities
72.6% for the period of 15 July–6 August): it reached R1 stage at 19 July, while peak trap captures were recorded at 6 August (peak capture at 3-day intervals 20.5 males/traps).
L1 larvae were found in the highest numbers on 2 August (1.5 larvae/50 cobs), practically in synchrony with peak caputres (LAG = 0).
“Káma” reached R1 stage in 16 July, and L1 larvae peaked at 2 August (1.3 larvae/50 cobs) (LAG = 0). On the rest of the corn varieties larvae were found only in too
numbers for performing statistical analysis. We conclude that in order to predict the appearance of L1 larvae, the phenological stage of the corn variety and the seasonal flight pattern of moths, as measured by large capacity
pheromone traps, should be considered in combination. If the corn variety already reached R1 stage, L1 larvae appear on cobs as early as the time of peak flight of moths. However, no young larvae appear on cobs despite of high
trap captures, until the corn reaches the R1 stage. These findings are discussed in the view of specifying optimal timing of a pesticide application. 相似文献
2.
Nabil E. El-Wakeil 《Journal of pest science》2007,80(1):29-34
The release of mass propagated egg parasitoids could be one option to control the lepidopteran pests. The efficiency of the
parasitoid Trichogramma evanescens (Westwood) reared on eggs of three different factitious hosts; Sitotroga cerealella, Ephestia kuehniella and Galleria mellonella was studied for controlling bollworm Helicoverpa armigera. Efficiency of Trichogramma was studied by measuring parasitism rates, emergence rates, longevity and sex ratio. Wasps reared from each source were tested
on the source host and on the target host, H. armigera under laboratory conditions. Rates of parasitism on H. armigera eggs, emergence rates of parasitoids and their longevity were the highest for wasps reared on H. armigera. Wasps reared on S. cerealella gave comparable rates. However, wasps from E. kuehniella gave the lower rates and G. mellonella gave the lowest ones. Parasitized eggs of H. armigera and S. cerealella produced more parasitoid females than eggs of E. kuehniella and G. mellonella. Results are discussed for magnifying efficiency of the parasitoid in controlling H. armigera in the field. 相似文献
3.
We evaluated the survival and growth of Abies homolepis and Picea jezoensis var. hondoensis seedlings on Mt. Ohdaigahara, where the population of sika deer (Cervus nippon) is high and an experimental fence has been in place for 13 years. No significant differences were detected in the survival
of small seedlings between fenced and unfenced plots. The growth of A. homolepis was significantly higher in the fenced plot, but growth of P. jezoensis var. hondoensis did not show significant differences between fenced and unfenced plots. Seedlings of height ≤5 cm in the forest floor vegetation
of the unfenced plot were probably too small for deer to find and browse, so they survived. 相似文献
4.
In the last 10 years, four species of psyllid were detected in Brazil on eucalypts: Ctenarytaina spatulata in 1994, Blastopsylla occidentalis in 1997, Ctenarytaina eucalypti in 1998 and Glycaspis brimblecombei in 2003. The latter two are serious pests in several countries. In Brazil, G. brimblecombei caused significant damage to the eucalypt plantations in the first years of its introduction. Now this pest is under control
due to the programmes of integrated pest management, where the parasitoid is the principal control agent. The four eucalypt
psyllid species introduced into Brazil are presented with information on distribution, hosts, biology and control. 相似文献
5.
利用扫描电镜观察了忍冬(Lonicera jàponica Thunb)和华南忍冬(Lonicera confus)叶表皮形态特征,观察指标包括:气孔器、表皮毛、表皮细胞等.结果表明:气孔仅分布在下表皮,气孔器呈无规则型散生;上表皮细胞的垂周壁呈沟槽状下陷;下表皮密被表皮毛(包括腺状毛和非腺毛),同时还分布有瘤状的草酸钙簇晶.为进一步证明这种瘤状结构是否为草酸钙簇晶,作者发现利用Fluo-3/AM(钙离子荧光指示剂)处理的活体叶片在激光共聚焦显微镜下能够发出强烈的荧光.此外,通过电子探针对瘤状物进行分析,发现其元素组成为C、O、Ca.上述叶表皮构造特征,有利于减少植物体水分散失,还有助于植物适应富钙的石灰土,从而适应我国西南岩溶区特殊的干旱、富钙的环境.电镜观察结果表明,在忍冬叶上表皮中脉处有呈线状分布的腺状表皮毛,而华南忍冬叶上表皮则无表皮毛分布,这一微形态特征可以作为二者种间特异性差别,从而为二者的合理区分提供一定的依据. 相似文献
6.
Masaki Fukuda Masayoshi Wakayama Masayuki Uchida Yukitaka Fukumasa-Nakai Teruyuki Matsumoto 《Journal of Wood Science》2007,53(4):339-343
Interspecific protoplast fusion between two monokaryotic strains (a methionine auxotrophic and chloramphenicol-resistant Pleurotus ostreatus strain and a wild-type strain of Pleurotus pulmonarius) was carried out to introduce mitochondrial DNA (mtDNA) from P. ostreatus into P. pulmonarius. Because mycelial colonies regenerated on minimum medium containing chloramphenicol only after the treatment of protoplast
electrofusion, the regenerants were regarded as protoplast fusants. The fusants isolated from regenerated colonies were uninucleate,
and their resistance of chloramphenicol seemed to be a stable trait. The fusants mated with P. pulmonarius but not with P. ostreatus, and showed almost identical random amplified polymorphic DNA (RAPD) patterns to that of the parental P. pulmonarius monokaryon. The sizes of mitochondrial genomes were estimated to be 81.5 kb for P. ostreatus monokaryon, 54.9 kb for P. pulmonarius monokaryon, and 84.5 or 86.0 kb for the fusants. BamHI and EcoRI digest patterns of the fusant mtDNAs were almost the same as the parental P. ostreatus monokaryon. From the above results, the fusants seemed to carry nuclei derived from the monokaryon of P. pulmonarius and mtDNA including the chloramphenicol-resistance gene from the P. ostreatus monokaryon, suggesting that the P. ostreatus mtDNA had been introduced into P. pulmonarius cells by interspecific protoplast fusion.
Contribution No. 383 of the Tottori Mycological Institute 相似文献
7.
The cotton whitefly, Bemisia tabaci (Genn.) (Hom., Aleyrodidae) is increasingly a very important pest on many vegetables, field crops and ornamental plants. Therefore,
controlling of this pest is still needed especially under glasshouse conditions. The specialist whiteflies’ predator, Serangium parcesetosum Sicard (Col., Coccinellidae) appears to have a great potential for the cotton whitefly control. In this study, the dynamic
changes in B. tabaci populations in glasshouse cabins in response to S. parcesetosum were monitored. B. tabaci were introduced to cotton plants in three cabins in average of 50 adults per plant. One and two weeks later, adult females
and males of S. parcesetosum were introduced at a rate of one female and one male per plant in the first and second cabins, respectively. The third cabin
was considered as a control. The results showed that the mean number of whiteflies in the control cabin was found significantly
higher than that of either when S. parcesetosum was introduced 1 or 2 weeks after the infestation with the whitefly. Also, the mean number of B. tabaci was significantly higher when the predator was introduced 2 weeks rather than 1 week after B. tabaci infestation. The maximum mean weekly number of whiteflies/plant was 192.3 in the second week, whereas it was 294.6 in the
third week and 1136.4 in the fifth week, in first, second and control cabins, respectively. In the last experimental week,
the mean weekly numbers were 74.7, 122.9 and 684.7 whiteflies/plant in the three cabins, respectively. S. parcesetosum has been successfully fed, reproduced and established its population on B. tabaci on cotton plants. The mean weekly number of the predatory individuals increased gradually with the progress of the experimental
time. The results demonstrated that the maximum reduction percentage in B. tabaci population was 90.7 and 86.5% in the fifth week after B. tabaci infestation, when the predator was introduced 1 and 2 weeks after the infestation with the whiteflies, respectively. Nevertheless,
it is speculated that an earlier release of S. parcesetosum would be more effective in the biological control of B. tabaci. 相似文献
8.
The cutting seedlings ofLiriodendron chinense xtulipifera were treated with the different concentrations of auxin (treatment1: IBA of 50 g·kg−1+NAA of 300 g·kg−1; treatment2; IBA of 100 g·kg−1+NAA of 300 g·kg−1). The biomass nutrient element contents for different organs (root, stem, leaf) of cutting seedling ofLiriodendron chinense xtulipifera were measured by the dry method, Kjeldahl method and Atomic Absorption Spectroscopy method. The result showed that the biomass
of root, stem, and leaf of the cutting seedling treated with auxin was all remarkably increased. The contents of element C
in root, stem and leaf had no significant difference between the control and auxin treatments, while the contents of N, P,
K and Ca in stem were much lower than that in leaf and root. Variance analysis showed that for the same organ with different
concentration treatment of auxin, the four nutrient elements (N, P, K, and Ca) had no significant difference in contents,
while there existed significant or very significant difference in contents of the four nutrient elements in different organs
with the same concentration auxin treatment. The N, P, K and Ca contents were very low in cutting seedlings; as a result,
additional fertilizer should be applied to the seedlings when they were planted in the field.
Foundation item: This paper was supported by Jiangsu Province Science Foundation (BE96350).
Biography: ZHANG Xiao-ping, (1972-), female, Ph. Doctor in Nanjing Forestry University. Nanjing 210037, P. R. China.
Responsible editor: Zhu Hong 相似文献
9.
Mostafa Haghani Yaghoub Fathipour Ali Asghar Talebi Valiollah Baniameri 《Journal of pest science》2007,80(2):71-77
The development of Diglyphus isaea (Walker), a parasitoid of leafminers, was studied under laboratory conditions at seven constant temperatures (10, 15, 20,
25, 30, 35, and 40°C) on Liriomyza sativae Blanchard reared on cucumber (Cucumis sativus L.). The total development period (oviposition to adult emergence) decreased with increasing temperature between 15 and 35°C.
In 10 and 40°C no development rate was found in D. isaea, so that it may be claimed that these temperatures fall outside the temperature range for development. Linear regression
was used to describe the relationship between development rate and temperature. For egg to adult development, males of D. isaea required 153.8 degree-days (DD) above the theoretical threshold of 9.2°C and females required 161.3 DD above 9.4°C. Data
were fitted to four nonlinear temperature-dependent models. Evaluation of the models took place based on the following criteria:
fit to data, number and biological value of the fitted coefficient, and accuracy on the estimation of the thresholds. It could
be concluded that the Briere-1 and Briere-2 models are suitable for estimating the minimum, maximum and optimal temperature
thresholds of D. isaea. Thermal requirements and temperature thresholds can be used to predict the occurrence, number of generations and population
dynamics of D. isaea. 相似文献
10.
M. Rostás 《Journal of pest science》2007,80(1):35-41
Maize seedlings contain high amounts of glucosidically bound 2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one (DIMBOA). The effects
of DIMBOA on the feeding behaviour and performance of two noctuids, Spodoptera exigua Hübner and S. frugiperda Smith, were compared. The question was raised whether S. frugiperda, preferring maize and other Poaceae, is better adapted to DIMBOA than S. exigua. In addition, the effects of DIMBOA on the mycelial growth of the plant pathogen Setosphaeria turcica Leonard et Suggs (causal agent of northern corn leaf blight) was assessed in vitro. DIMBOA had an antifeedant effect on S. exigua but stimulated feeding in S. frugiperda in dual-choice experiments. In a no-choice setup, larvae of S. exigua gained less biomass and had a prolonged development when feeding on an artificial diet containing DIMBOA. However, pupal
weight was not significantly different between treatments. In contrast, larvae of S. frugiperda were not affected by DIMBOA. Strong detrimental effects of DIMBOA were found on the mycelial growth of the pathogen S. turcica. 相似文献
11.
Red clover (Trifolium pratense L.) is becoming increasingly important in grassland systems because of its high productivity, protein content and nitrogen-fixing
ability, but its use has been constrained by losses due to pests and diseases, and this contributed to the decline of red
clover usage allowing white clover (T. repens L.) to become the dominant legume of UK grasslands. One of the major pests of red clover is the clover root weevil (Sitona lepidus Gyllenhal, Coleoptera, Curculionidae) which attacks both the shoots and roots, particularly the N-fixing root nodules, of
clover plants. This current work investigates the feeding preferences of S. lepidus with respect to 11 varieties (Pawera, Kuhn, Astra, Norseman, Norseman low, Norseman high, Marcom, Merviot, Milvus, Britta,
Sabtoron) and 5 lines (AA30, AA31, AA4493, AA4494 and AA4495) of red clover in order to identify relationships between the
variation in attractiveness of different red clover varieties for both adult and larval stages of the weevil. Of those tested
Norseman high showed potential resistance, being less favoured by both adults and larvae of the weevil. This may be attributed
to the potentially high phyto-oestrogen levels in this variety. 相似文献
12.
XIANGYong LIUJun LUAn-guo CUlJing-xia 《林业研究》2003,14(3):217-220
Endophytic fungi are widely found in almost all kinds of plants. Many endophytic fungi can produce some physio-logical active compounds, which are same to or analog to those isolated from their hosts. Producing physiological active compounds through microbial fermentation can give a new way to resolve resource limitation and to find out alternative source.Through the methods of organic solvent extraction, thin layer chromatography (TLC) and column chromatography, compound I was isolated, purified from the liquid fermentation metabolites of the taxoids-produced endophytic fungi (Altemaria. altemata var.taxi 1011 Y. Xiang et LU An-guo) that was screened from the bark of Taxus. cuspidata Sieb.et Zucc.. Compound I was identified as one kind of taxoids type Ⅲ, based on the analyzing results by using the methods of ultraviolet spectroscopy (UV), infrared spectroscopy (IR), mass spectrometry (MS) and nuclear magnetic resonance spectroscopy (NMR). This study provides a completed method for separation and purification of the endophytic fungi as well as structure identification of its fermentation metabolite 相似文献
13.
In 2000, one-year-old seedlings of pyrenean oak (Quercus pyrenaica Willd.) and sessile oak (Quercus petraea [Matt.] Liebl) were planted in a thinned and an unthinned plot in a pinewood (Pinus sylvestris), and in a nearby clearing. In summer 2002 and 2003, water relations and gas exchange parameters were measured to address the impact of drought on the seedlings. Chlorophyll a fluorescence was also measured to explore leaf photochemistry and a possible non-stomatal limitation to photosynthesis (A). Reduction in stomatal conductance (g) in response to the decrease of predawn water potential (Ψpd) resulted the main cause affecting net carbon uptake. Water potential at midday (Ψmd) was similar in both species but Quercus petraea was more sensitive to soil water deployment occurred along summer, showing slightly lower Ψpd because worse recover of water potential during night. Rate of photosynthesis was higher in Q.␣pyrenaica probably in relation to its greater leaf mass per area (LMA) and nitrogen content per leaf area (Na). Mortality was highest in the clearing and lowest in the thinned pinewood. Throughout the summer, soil moisture was higher in the thinned area, possibly because of the reduction in tree transpiring surface and interception of rainfall. Accordingly, Ψpd of both species was higher in the thinned site. 相似文献
14.
Taira Hideaki 《Journal of Forest Research》2003,8(3):227-229
To clarify key characteristics of the process whereby dormancy is released in male flowers of Cryptomeria japonica, twigs with male flowers were collected every three days between December 1992 and February 1993. Half of the twigs collected on each date were chilled at 0°C for three days and the cumulative temperatures required by the chilled and non-chilled flowers for florescence were compared. There was no difference in the cumulative temperature required for florescence between chilled and non-chilled male flowers collected before 19 December. However, for samples collected between 21 December and 21 January, the cumulative temperature needed for the florescence of chilled male flowers was 8–68°C lower than that required for non-chilled male flowers. However, there was little difference again in the cumulative temperature required to induce the florescence of chilled and non-chilled male flowers for collection dates later than 24 January. These results suggest that the dormancy of male C. japonica flowers was gradually released by exposure to low temperature and the process was completed by 24 January. The cumulative temperature required for florescence and the sum of the mean daily temperatures between the date of collection and the date of natural pollen dispersal were almost equal after the dormancy of the male flowers was released. The exact day on which pollen will be released can be predicted using the dormancy characteristics of male flowers. 相似文献
15.
General biology, seasonal flight numbers and ovipositional data were gathered to understand the phenology of the cherry bark
tortrix, Enarmonia formosana Scopoli in Seattle, WA. Pheromone trapping during 2001 and 2002 showed a continuous flight period from May to September.
During this time the greatest abundance of adults occurred during July and August. The combined seasonal egg data and larval
developmental times indicate E. formosana is a univoltine species in the Pacific Northwest. Field releases of Trichogramma cacoeciae Marchal increased E. formosana egg parasitism on individual trees. During the two years, parasitism levels ranged from 72 to 74%. 相似文献
16.
Kamil Karut 《Journal of pest science》2007,80(2):93-97
Efficient use of parasitoids in pest control depend on the knowledge of the biological relationships between host and parasitoid.
Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae) is one the most important natural enemies of Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae) that is found in fields and greenhouses in Adana, Turkey. Although more studies have
been done to determine the relationships between E. mundus and B. tabaci, the differences among strains of E. mundus could have important biological concequences. In this study, biological characteristics of native population of E. mundus parasitization of B. tabaci (Q biotype) were determined using bean plants Phaseolus vulgaris (L.) at a constant temperature of 25 ± 1°C, relative humidity 70 ± 10% and 16:8 (L:D) photoperiod regimen. All B. tabaci nymphal instars were parasitized by E. mundus, but the mean number of daily-parasitized nymphs was highest in the second instars (15.3). In addition, second instar females
had the shortest mean development time (15.2 days). Mean development times of parasitoids obtained from first, second, third
and fourth B. tabaci instars varied from 15.2 to 16.2 days and 15.2 to 15.9 days for female and male, respectively. Proportion of female (♀/♂+♀)
varied from first (0.53) to second (0.34) host instars. Impact of results on potential biological control of B. tabaci was discussed through conservation native natural enemies. 相似文献
17.
Rhyzopertha dominica (Fabricius) has developed extensive pesticide resistance in the last several decades. We have developed a supercritical fluid
extraction method for Trigonella foenum-graecum L. (TFG) and studied the contact toxicities of the extracts to R. dominica. The extraction method was designed with orthogonal experiments to preserve and collect all the possible active components.
Contact toxicity and efficiency of extraction were used as standard values to optimize extraction conditions, which were achieved
at 55°C under 25 Mpa of pressure. The extraction efficiency for 200 g of dry sample reached 6.21% with 30 ml of 95% alcohol.
Extracts loaded on filter paper showed dose and time dependent toxicities to adult R. dominica with a LC50 value of 65.02 μg/cm2 after 3 days post treatment. Our extensive in vivo studies indicated the extracts from Trigonella foenum-graecum seeds have high efficacy against pesticide resistant R. dominica. The active ingredient(s) from the extract shows promise as a novel pesticide candidate. 相似文献
18.
Noriaki Katsumata Tsuyoshi Yoshimura Kunio Tsunoda Yuji Imamura 《Journal of Wood Science》2007,53(4):320-323
Any means helpful for the promotion of termite feeding activity has potential for use in a matrix in termite bait application.
Therefore, energy transfer by gamma irradiation is worthy of consideration for converting wood into termite-accessible material.
Wood specimens gamma-irradiated at 100 kGy and at lower levels were tested for their degrees of polymerization (DP) of cellulose
and biological resistance. The DP of cellulose adversely decreased with increased doses of gamma irradiation. Termite wood
consumption rates, which were determined by laboratory tests using undifferentiated larvae (workers) of Coptotermes formosanus Shiraki, were significantly higher at 100 kGy than at other doses. On the other hand, the decay resistance of gamma-irradiated
wood against the fungi Fomitopsis palustris (Berkeley et Curtis) Murrill and Trametes versicolor (L. ex Fr.) Quel did not vary by irradiation dose. 相似文献
19.
The development, longevity, fecundity and life-table parameters of the endoparasitoid Anagyrus pseudococci (Girault) (Hymenoptera: Encyrtidae), 15 d.o. (3rd-instar nymphs) and 21 d.o. (young adult females) of the vine mealybug,
Planococcus ficus (Signoret) (Hemiptera: Pseudococcidae) at 28 ± 1°C, 65 ± 10%RH and 16:8h L:D under laboratory conditions. The developmental
time of female parasitoids within the host was 17.7 ± 0.39 days in 15 d.o. and 16.65 ± 0.25 days in 21 d.o. hosts; for males,
development time was 16.85 ± 0.29 and 15.25 ± 0.09 days, respectively. The average number of offspring per female was 22.35 ± 1.68
in 15 d.o. and 34.8 ± 2.56 in 21 d.o. vine mealybugs. The longevity of female parasitoids was 14.8 ± 0.98 days in 15 d.o.
and 15.65 ± 0.92 days in 21 d.o. mealybugs, respectively; for males, longevity was determined as 7.3 ± 0.43 and 6.7 ± 0.54 days,
respectively. The mean time of pupation was 7.85 ± 0.003 days in 15 d.o. mealybugs and 8.65 ± 0.003 days in 21 d.o. mealybugs.
The aggregate encapsulation rate in the parasitized 15 d.o. mealybugs was 49.73 and 60.36% in 21 d.o. mealybugs. Furthermore,
effective encapsulation was 24.82% in 15 d.o. mealybugs and 37.50% in 21 d.o. mealybugs. Population growth rate (r
m) for A. pseudococci was 0.0999 female/female/days in 15 d.o. mealybugs and 0.1269 female/female/days in 21 d.o. mealybugs. The mean population
generation time was 23.49 days for parasitoids reared in 15-days-old and 22.39 days when reared in 21 d.o. mealybugs. 相似文献
20.
ZHOULi DAILi-min SUBao-ling 《林业研究》2003,14(3):213-216
Embryo of lilacs (Syringa L) culture in vitro and the rapid propagation were studied. The orthogonal experiments, including the selection of basal medium, embryo age and other factors such as sugar, benzyladenine (BA), naphthalene acetic acid (NAA) and glutamine (Gln), were carried out. The results indicated that the optimal medium for embryo culture was Monnier medium supplemented with NAA (0.001 mg.L^-1), BA (0.1 mg.L^-1), sugar (50 g.L^-1), and Gin (400 mg.L^-1), with a germination rate of 91.7% at least; the optimal embryo age was 50 d; and Gln had significant effects on the germination rate of embryo.Moreover, the optimal medium for subculture was MS BA (2 mg.L^-1) NAA (0.001 mg.L^-1) Gln (0.5 mg.L^-1), with the propagation coefficient of 3.6 at least. 相似文献