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1.
The “Black Stripe Moth Trap”, a funnel type one (commercially available from AgriSence Inc.) designed for monitoring storage and field moths, was tested in tobacco stores in order to evaluate its effectiveness onLasioderma serricorne. The experiment took place for a 12 months-period (in 1996), in a private warehouse in Thessaloniki, Macedonia, Greece. The trap was applied baited (with 15 mg “serricornin”) and unbaited (control). The pheromonic trap has shown an impressive efficacy in trapping the tobacco beetle adults as it caught ∼95.4% of the total number of the insects, during the whole experimental period.  相似文献   

2.
Freezing of tobacco balls (Brasil, 90×50×50 cm.) and boxed cigars in a cold room at ?20°C was found to control the larvae of the cigarette beetle satisfactory. All test larvae in the center of balls and boxed cigars were killed at a temperature of ?12°C which was reached after 11 respectively 14,5 hours.  相似文献   

3.
Studying the biotope of Lasioderma serricorne (F.) in tobacco stores during 2001 and 2002, we identified the ectoparasitoid Lariophagus distinguendus (F.) which parasitises various beetle species. L. distinguendus is reported for the first time in Greece to parasitise L. serricorne in tobacco stores.  相似文献   

4.
Tobacco was fumigated to control the cigarette beetleLasioderma serricorne (Fabr.) with a fumigant based on magnesium phosphide (Detiaphos R) in hogsheads and cartons at temperatures almost constantly below freezing point and alternatively at temperatures which increased or decreased very slowly in the course of the fumigation. The dosage was 1 g PH3 per m3 and the fumigation lasted 96 h in all cases. Gas concentration measurements in the tobacco and under sheeting showed that PH3 developed rapidly in lethal concentrations from magnesium phosphide at low temperatures. Complete mortality of the inserred test insects was registered after the 96 h fumigation period. With magnesium phosphide, a fumigant is available which can be used for fumigating tobacco even at low temperatures.  相似文献   

5.
6.
In this paper, 4N-HCLAIA method was adopted to conduct digestive tests in young female and male Dongtian F1 red deer (Cervus elaphus) of rearing seperately in growth period and mixed raising in weaning period in Harbin Specialty Research Institute. Results indicated that digestive rate of crude protein and crude fiber were 95.35% and 73.68% respectively when rational protein content was 26.8% in growth period, Digestive rate was not significantly different between female and male(P>0.05); During weaning period, when rational crude protein content is 22.06%, digestive rate of crude protein and crude fiber were 93.05% and 63.96%, respectively. The tests suggest that higher rational protein can be effective in accelerating growth of young Dongtian F1 red deer during growth period and weaning period(before 10 months old). (Reponsible Editor: Chai Ruihai)  相似文献   

7.
Trenching and shoot removal showed the relative influences of living roots and the canopy cast by teak (Tectona grandis L.F.) coppice regrowth on the growth and yield of interplanted maize (Zea mays L.). Teak and maize were planted at 1.8 × 1.8 m and 0.3 × 1.8 m spacing respectively.Competition for light started about four weeks after planting and caused etiolated height growth of maize. When combined with root competition it caused stunted growth. Shading also substantially reduced total dry matter production, grain yield, number of cobs per plant, average cob weight, and weight of grains per cob of maize (P<0.01). Living teak roots alone did not have a significant effect (P>0.05) on maize height growth, total dry matter production, grain yield, number of cobs per plant,average cob weight and weight of grains per cob. However, combined with shading, living roots of teak appreciably reduced total dry matter yield and average cob weight of maize (P<0.01).  相似文献   

8.
Aromatic spice crops such as coriander, Coriandrum sativum L., and fennel, Foeniculum vulgare L., are among the major seeds exported to the international market. Observations on the stores of these crops revealed differences in their susceptibility to the cigarette beetle, Lasioderma serricorne (F.) (Col., Anobiidae). Coriander seeds proved to be the most appropriate diet for the beetle. The population dynamics of L. serricorne (F.) was determined, showing 3 generations during the period from May to October.  相似文献   

9.
Teak (Tectona grandis Linn F.) is a popular exotic species in Ghana, widely grown in industrial plantations and small scale community woodlots. In spite of its importance, local information on the growth and yield of this species is lacking. Presented here are the results of a preliminary investigation into the growth and yield of teak in northern Ghana. Data were collected from 100 temporary sample plots from plantations ranging in age from 3 to 40 years. A standard volume equation, site index curves and provisional empirical yield tables were developed and presented. Site index curves were used to classify plantations into site classes of I, II and III, in order of decreasing productivity. Yield functions indicate that teak can be grown on biologically optimum rotations of 31, 38 and 48 years on site classes I, II and III, respectively. At extended rotations with the adoptions of suitable thinning schedules, trees of sawlog sizes could be obtained on site class I.  相似文献   

10.
Tropical insect species show year-round breeding activity due to favourable climatic conditions. However, most species also display seasonal reproductive peaks, but little is known about underlying causes of temporal density changes. We investigated population dynamics of the pest predator Rhynchium haemorrhoidale (F.) (Hymenoptera: Eumenidae) and its natural enemies in relation to season, climate and varying shade tree composition in cacao agroforestry systems in Central Sulawesi (Indonesia). Nesting of R. haemorrhoidale showed clear seasonality with highest densities in the wet season and lowest in the dry season, which was not related to changes in temperature. Wasp densities increased with land-use intensity, presumably because less-shaded areas offer more favourable climatic conditions and higher densities of the major prey, the cacao pest Agathodes caliginosalis (Lepidoptera: Pyralidae). Pupal body size was higher in June than in November indicating increasing intraspecific competition due to high wasp densities and food shortage at the beginning of the wet season. Body size between habitat types was similar, thus season appeared to be more important than habitat in terms of food supply. High wasp densities in the wet season were associated with high diversity of the altogether seven parasitoid species. In conclusion, we found a pronounced seasonality of the wasp R. haemorrhoidale and a preference for little shaded agroforestry, which may be due to enhanced temperature and density of its prey. Our data indicate a high potential for biological control of a major cacao pest by management of nesting sites of R. haemorrhoidale.  相似文献   

11.
Nutrient accessions to the forest floor in rainfall, throughfall and stemflow from the understorey and tree strata were measured in karri (Eucalyptus diversicolor F. Muell.) forest of south-west Western Australia. These data, for stands aged 2, 6, 9, and 40 years and for mature forest, were compared with annual accessions of nutrients in litterfall.

With increasing age of the stands, the concentration and amounts of Ca, K, Mg, Na and Cl in throughfall increased. The amounts of Mg, Na and Cl in stemflow from the overstorey were also greatest in the older stands. Although concentrations of nutrients in stemflow from the tree stratum were higher than from the understorey, the quantities of nutrients transported to the forest floor in stemflow from the understorey were greater because of its greater volume.

Rainfall is the major source of Na (64–91%) and Cl (51–79%) and it also contributes significantly to Mg (19–50%) accessions. Of the nutrient pathways between canopy and forest floor, litterfall accounts for the largest proportion of N (89–93%), Ca (80–87%) and P (67–79%) recycled in the karri forest. About equal amounts of K are transferred in litterfall, throughfall and stemflow with approximately 80% of stemflow K originating from the understorey strata.  相似文献   


12.
Five insect growth regulators, CGA-29170, CGA-45128, MV-678, RO-20458, and fenoxycarb, that exhibit juvenile hormone activity were evaluated for biological and residual activity against the southern cowpea weevil,Callosobruchus maculatus (F.). The compounds were mixed with cowpea seeds at concentrations of 10, 25, 50, and 100 mg/kg, and the residual activity was evaluated at 2-week to 9-months posttreatment intervals. Most JHA-treatments showed high initial activity at the 2-week interval resulting in a significantly lower oviposition rate and showing a short residual life in this respect. CGA-45128, however, at all concentrations tested did not significantly affect oviposition at 2-week to 4-month posttreatment intervals, where was more active and caused high depression in oviposition at 6-month interval. The juvenoids had an inductive effect on the percent egg hatch at various intervals, especially CGA-29170 and CGA-45128 treatments extinding over a period of 9 months. At the lower concentration of 10mg/kg, CGA-45128 was highly effective as F1-progeny suppressant ofC. maculatus at 2-week posttreatment interval extending over 9 months. MV-678, CGA-29170, and fenoxycarb applied at 50, 50, and 25 mg/kg, respectively, showed similar activity, however, the residual activity of the latter decreased after 4 months. RO-20458, however, showed high initial activity at these concentrations. Adult emergence in all treatments was significantly suppressed, where did not exceed 29.5% at the lower concentrations of 10 and/or 25 mg/kg at 9-month posttreatment interval.  相似文献   

13.
Observations are given on phaenology and bionomy ofP. revestita in South Tyrol last years. The larvae develop exclusively within dead stumps of branches near the living tissue. The first attack shows secondary character but later the feeding can become primary. The time of flight occurred mainly in the middle of May. The quota of females amounted to 50% in the laboratory but only to 14% in the field. Apparently the males show more activity of flight than the females. The beetles swarm in the crowns of host trees about noon.  相似文献   

14.
Nine half-sib families of maritime pine (Pinus pinaster Ait.) of known adult performance were grown in continuous light at either 25 degrees C or 25/20 degrees C for 18 weeks. They were then exposed to a dormancy induction period followed by a dormancy release period and then grown for a further 9 weeks in a 16-h photoperiod at a day/night temperature of 25/20 degrees C. Seedlings exhibited great diversity in morphology at the end of the first growth period. The number of morphogenetic cycles varied between one and three and the form of the apical meristem ranged from a typical rosette to an adult-like bud. The type of seedling obtained at the end of the first growth period strongly influenced later growth, independently of the temperature regime. Maturity was proportional to the number of morphogenetic cycles achieved during the first growth period and was characterized by short growth duration, small primary needles and a high degree of fixed growth. The state of the apical meristem that underwent the dormancy period had less influence on the rate of maturation than the number of morphogenetic cycles. The time course of maturation was endogenously controlled and varied among traits. Conspicuous morphological differences were not associated with changes in the relationship between growth components at the phenotypic level. However, there seemed to be a shift in the genetic correlations between growth components after first budset.  相似文献   

15.
Zusammenfassung Die Nachkommenzahl von einem Weibchen vonSitophilus oryzae oderSitotroga cerealella in Sorghum-Körnern nahm mit dem Ansteigen der ursprünglichen Elterndichte ab. Jedoch nahm die Gesamtzahl an Nachkommen beiS. oryzae bis zu einem Maximalwert zu und danach bei weiterem Anstieg der Elterndichte wieder ab (Crowding-Konkurrenz). BeiS. cerealella dagegen tendierte die Nachkommenzahl dazu, von einem Grenzwert ab—unabhängig von der Elterndichte—konstant zu bleiben (Wettkampf-Konkurrenz).
Intraspezific competition and progeny production inSitophilus oryzae (L.) (Coleopt.) andSitotroga cerealella (Oliv.) (Lepid.) in Sorghum grain
The number of progeny produced per femaleSitophilus oryzae (L.) orSitotroga cerealella (Oliv.), on sorghum grain, decreased as the initial parental density increased. However, the total number of progeny (off-springs) produced inS. oryzae increased to a peak then declined with further increases in parental density (Scramble competition). InS. cerealella the progeny produced tended to be fairly constant once a certain parental density was passed (Contest competition).


Mit einer Tabelle  相似文献   

16.
The effect of solarization on the development of Callosobruchus maculatus was investigated in the Nigerian savanna during the hot season from April to May, 1999. Development of C. maculatus adult progeny was completely suppressed in seeds of bambara groundnut, Vigna subterranea bearing bruchid eggs or harbouring first and second instar larvae that were exposed to the sun in metal tins, clay pots or polypropylene sacks for 7, 14 or 28 h. Adults of C. maculatus developed only in seeds that were not exposed to sun. Solarization did not have a significant adverse effect on germinability of bambara groundnut seeds.  相似文献   

17.
在湖南省洪江市选择与云南文山三七主产区气候条件相似的猕猴桃林、杉木林、阔叶林、核桃林、葡萄林等5种林地,在林地采集土样,测定其土壤养分含量及pH,并与文山三七种植地的土样测定结果进行对比分析。结果表明:阔叶林地、核桃林地、猕猴桃林地含K量较低,需多施K肥;杉木林地含P量较低,应多施P肥。在以上湖南洪江5种林地的林下种植三七,并合理施肥,采收其肉质根与文山种植的三七进行有效营养成分对比分析,发现两者的产量和品质无明显差异。  相似文献   

18.
During last years, the populations of the oak buprestid beetleAgrilus biguttatus (Fab.) in Europe have increased. In several countries, the beetles’ attacks have become a new component in oak dieback. The larvae excavate galleries under the bark of weakened trees, which are killed through the girdling. Because of the difficult diagnosis it is necessary to draw more attention to the infestations. Therefore, this paper presents a review on the literature concerning the recognition of the infestations by the insect and its bionomics.  相似文献   

19.
The attraction of Scolytus scolytus (F.) to the four enantiomersof 4-methyl-3-heptanol, the major component of the aggregationpheromone, was studied in the field. Only the (–)–threoisomer attracted significantly more beetles than the blank (control),and the response to this isomer was not significantly differentfrom the response to commercial 4-methyl-3-heptanol, which containsall four isomers. There was no evidence for inhibition of attractionby the other three isomers. Commercial 4-methyl-3-heptanol couldtherefore be used, in combination with other components of theaggregation pheromone, for population sampling and control bymass trapping of S. scolytus.  相似文献   

20.
A series of experiments were conducted in which label rate (0.3 g per kg of wheat) with diatomaceous earth (DE) formulation Protect-It. Exposure studies were carried out at two levels of relative humiditiy (40% and 55%), two levels of insect density (10 or 20 adults per vial), and three levels of exposure periods. Test insects were placed in vials containing 40 g of soft white winter wheat mixed with either 0 or 0.3 g Protect-It per kg of wheat. After relating exposure periods for both insect density and relative humidity levels, highest mortality was only 16%. Mortality, regardless of the dose rate applied (0 and 0.3 g) were not significantly increased as the exposure period increased. Regardless of relative humidity (r.h.) (40% and 55%r.h.), mortality in control were not significantly increased as the exposure period increased for the same insect density. However, significant differences among the three exposure periods in 10 adults’ density in 0.3 g DE application. Mortality was significantly increased in 10 adults’ density. In this case mortality of R. dominica adults increased with the increasing of the exposure intervals. As for 20 adults’ density, mortality in 0.3 g DE application was not significantly changed along with the exposure intervals. After insects were exposed for 1, 2, or 3 week, dead and live insects were removed, and the wheat in the vial were returned to relating humidity box and kept for 8 week until F1 adults emerged. Then, the number of F1 adult was counted. The mean numbers of F1 adults on untreated wheat at all density and r.h. combinations, regardless of exposure periods were significantly higher than that of 0.3 g DE- treated wheat (Fig. 3). At each density and treatment, the mean number of F1 adults at 55% r.h. were higher that that of 40%r.h. The comparison between adult densities at each r.h. and treatment showed that adult densities influenced the F1 production of R. dominica and F1 adults were always higher at 20 adults’ density. The mean number of F1 adults at each density, regardless of treatment progressively increased as the exposure period increased. Fewer progeny were produced at 10 adults’ density compared to 20 adults’ density for same exposure periods. The highest reproduction occurred in 3 week of exposure period for both insect densities. Regardless of adult densities, the mean number of F1 adults was significantly increased as the exposure period increased (Fig. 5) for both control and 0.3 g DE treatment. Reduction of F1 adults at 0.3 g DE application compared to control were found to be 76.88, 74.78 and 67.63% for 1, 2 and 3 week of exposure period, respectively.  相似文献   

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