Dormancy induction in container-grown Abies seedlings: Effects of environmental cues and seedling age

Twelve-week-old container-grown seedlings of noble fir (Abies procera Rehd.) and Shasta red fir (A. magnifica A. Murr. var. shastensis Lemm.), both high-elevation species, were grown under controlled environments in a study of induction of terminal-bud dormancy. Eight treatment combinations of long (15 h) or short (11 h) photoperiods, warm (25°/20°C) or cool (18°/12°C) thermoperiods, and dry (–1.2 MPa) or wet (–0.6 MPa) moisture regimes were imposed upon seedlings for 12 weeks. Treatment factors significantly affecting the induction of dormancy in terminal buds of seedlings were identified over time. The results suggest that seedlings responded dynamically to dormancy cues. The warm/dry and cool/wet combinations induced dormancy in the first 2 weeks in noble fir and in the first week in Shasta red fir. Short-day/warm and long-day/cool combinations enhanced dormancy induction in weeks 3 to 4 in noble fir and in weeks 1 to 7 in Shasta red fir. Short days and cool thermoperiods independently hastened dormancy induction in noble fir in weeks 5 through 12.     

Sensory evaluation of carpet cleaner containing essential oil and the effect on mites

We prepared carpet cleaners containing three wood oils extracted from Thujopsis dolabrata Sieb. et Zucc. var. hondai Makino, Chamaecyparis obtusa Endl., and Chamaecyparis taiwanensis Masamune et Suzuki and studied their effects on mites and perfumerists' impressions. The oil concentrations were set at 0.1%, 0.2%, 0.4%, 0.8%, and 1.6%. The effects on Dermatophagoides pteronyssinus Trouessart were investigated. The sensory evaluations were conducted by seven male perfumerists using the SD method and they were asked to describe freely their impressions of the scents. These results showed that: (1) all three types of wood oil had a significant effect on making D. pteronyssinus inactive at 0.1% concentration; and (2) the wood oil of T. dolabrata evoked refreshing, natural, rich, and intellectual feelings; C. obtusa oil evoked vivacious, rich, and intellectual feelings; and C. taiwanensis evoked refreshing, natural, rich, rough, masculine feelings. According to the test subjects, T. dolabrata evoked woody and earthy impressions; C. obtusa evoked woody, citrus, and pine-resin impressions; and C. taiwanensis evoked woody, citrus, and medical impressions. Many issues remain to be investigated, but the inclusion of wood oil in carpet cleaners offered both good mite control and a pleasant aroma to humans. This study suggests a new potential for using these wood oils.     

Hinweise zur Auswirkung biophysikalischer Umweltverhältnisse auf forstschädliche Insekten,untersucht insbesondere anLymantria monacha L.

Zusammenfassung Die Zentren des Schadauftretens verschiedener untersuchter forstschädlicher Insekten dürften nach zahlreichen Testungen Reizzonen umfassen, welche wieder als eine Kombination von elektrischen und magnetischen Feldern und durch diese freigelegte Metalleffekte erscheinen. Untersuchungen zur möglichen Wirksamkeit dieser Komponenten auf Vitalität und Fertilität vonLymantria monacha führten zu folgenden Ergebnissen. Es erscheint möglich, daß innerhalb von Reizzonen Sterblichkeit und Fruchtbarkeit vonLymantria monacha auch von niederfrequenten elektromagnetischen oder auch konstanten magnetischen oder elektrostatischen Feldern beeinflußt werden, die direkt oder auch über die Pflanze auf die Lebenskraft der Nonne von Wirksamkeit sind. Reizzonenbereich und Normalbereich zeigten hinsichtlich der Mortalität der Versuchstiere gegensätzliche Verhältnisse. Die Anfangsmortalität innerhalb von Reizzonen war gegenüber jener der Zuchten im Normalbereich erniedrigt, die Endmortalität vielfach erhöht. Futter aus Normalbereichen setzte in den Reizzonen, Reizzonenfutter im Normalbereich die Sterblichkeit herab und erhöhte im Normalbereich die Fruchtbarkeit. Im Normalbereich mit Normalfutter gezogene Nonnen wiesen die geringsten Zahlen an abgelegten Eiern auf, was sich besonders bei an Pflanzen eingebeutelten Tieren deutlich zeigte. Die wesentlich höhere Fruchtbarkeit von Nonnen an Pflanzen im Reizzonenbereich mag zusammen mit der hier erniedrigten Anfangsmortalität eine Erklärung zum gehäuften Auftreten vonLymantria monacha innerhalb von Reizzonen geben. Freigesetzte Metalleffekte könnten innerhalb von Reizzonen die Sterblichkeit aber auch die Fruchtbarkeit erhöhen.

---

Summary The centres of damages by different forest insects, examined in this research, seem to be in zones of Earth radiations (Reizzonen), which again seem to be combinations of magnetic or electric fields and metal effects, set free by them. Examinations for possible influences of these components on vitality and fecundity ofLymantria monacha showed the following results: It seems possible, that inside of zones of earth radiations mortality and fecundity of this butterfly could be directed from magnetic or electric fields also of low frequency or electrostatic, which either directly or indirectly by the nutrients (plants) influence the vital power ofLymantria monacha. Zones of Earth radiations and normal zones showed different conditions in respect of the mortality. Mortality of larvae of first developmental stages inside of zones of Earth radiations was decreased, such of late stages increased contrary to larvae in normal zones. Plant-food of normal zones decreased the mortality of larvae in zones of Earth radiations and food of zones of Earth radiations decreased the mortality of those of normal zones and increased fecundity in the latter cases. Female butterflies reared in normal zones showed the lowest number of developed eggs, especially when reared encaged on living plants (spruce). The essentially higher fecundity ofLymantria monacha reared on plants inside of zones of Earth radiations together with the decreased mortality of first instar larvae there, may give an explantation for the increased population ofLymantria monacha inside of zones of Earth radiations. Metal effects set free inside of zones of Earth radiations could increase there the mortality but also the fecundity.

---

---

Herrn Prof. Dipl.-Ing. Dr. ERWIN SCHIMITSCHEK zum 75. Geburtstag.

---

A 1130 Wien XIII, Fasangasse 5-7, 1/8     

Stock quality and field performance of Pinus patula seedlings produced under two nursery growing regimes during seven different nursery production periods

Two types of containerized P. patula seedlings, referred to as hard and soft seedlings, were raised by droughting and different fertilizer applications. Hard seedlings were raised by applying half the water and a quarter of the fertilizer (0.01 g per seedling 21%N:7.1%P:14.2%K) applied to the soft seedlings. At the end of the nursery cultural treatments the two types of seedlings were morphologically distinct. Hard seedlings had lower heights, height to root collar diameter ratios and seedling dry masses than soft seedlings, but mortality was similar for both seedling types when planted during seven different production periods within the planting season on three sites which differed climatically and geologically. Correlations between mortality and height to root collar diameter ratio (r = 0.76), root to shoot ratio (r = 0.83) and root growth potential (r = --0.69) were obtained indicating that grading of seedlings on these parameters may improve survival. However, it was evident that survival could be significantly improved by identifying the best time of year and conditions for planting, as well as improving stock quality.     

General laws of wood deformation and rheological propertions of hardwood

Summary Characteristic features of wood deformation under loading at changing moisture contents (temperature) are discussed on the basis of results from rheological tests with hardwood. General laws of deformation in wood as a result of various cyclic effects of loading as well as of temperature and moisture content have been established. These laws have been used to solve the problem of the plane stress state in lumber when dried by using the method of finite elements. To control internal stresses and for an effective drying process, it is suggested that differential shrinkage should be measured, i.e. the difference between the displacements of points on Both verges of the board's edge and in the centre of the edge.Presented at the Meeting of the European-African Group of IAWS with the topic Structure and Utilization of hardwoods, Banska Bystrica, CSSR, September 9–11, 1975.     

Predicting field performance using seedling quality assessment

Seedling quality is defined as fitness for purpose. Attributes for assessing seedling quality are grouped in material attributes that can be rapidly assessed by any number of direct or indirect methods, and performance attributes that are assessed by subjecting whole seedlings to certain environmental regimes and evaluating their growth response. Material attributes comprising morphology, bud dormancy, water relations and nutrition and performance attributes comprising frost hardiness, vigour and root growth potential are discussed with regard to relevance for predicting field performance. Measurement techniques and relevance in assessing seedling quality are presented for different physiological attributes: electrolyte leakage, enzymatic activity, water potential, water conductance, mineral nutrition, food reserves, mitotic index, gas exchange, chlorophyll content, plant growth regulators, stress-induced volatile emission, and nuclear magnetic resonance. Methods with future potential in improving the prediction of field performance are identified and discussed. The methods presented in this respect are chlorophyll fluorescence, infrared thermography, machine vision systems, integrated approaches and ecophysiological evaluations.     

White spruce establishment: initial fertilization,weed control,and irrigation evaluated after three decades

Outplantings of white spruce (Picea glauca [Moench] Voss) in a factorial experiment in 1962 (P62) and 1963 (P63), near Ottawa, Ontario, addressed the problem of prolonged unsatisfactory growth of outplanted white spruce, a condition commonly termed check. Applied in the first 2 growing seasons, the treatments (3 levels of nitrogenous fertilization ×± weed control ×± irrigation) subjected the trees to differential fertility and soil moisture on each of three soils (clay, loam, and sand). There were 5 (P62) and 6 (P63) replications of 9-tree plots. The P62 Loam planting was destroyed by fire in 1966. Initial survival in the P63 Clay was too low to warrant long-term monitoring. Monitoring of the P62 Clay planting was discontinued after 20 years when it was clear that site factors unrelated to the experimental treatments were controlling stand development. After 30 growing seasons in the P62 Sand and 29 growing seasons in the P63 Sand and P63 Loam plantings, neither initial nitrogenous fertilization nor initial irrigation was influencing performance, but on all three sites the positive effect of initial weed control remained significant (P<0.001).     

Über Einflüsse biophysikalischer und elektrischer Felder auf Lymantria monacha L.

Influences of biophysical and electrical fields on Lymantria monacha L. Caterpillar migrations, Faraday experiments, physical measurements Examinations of caterpillars migrations ofLymantria monacha in respect of biophysical food sources (food of normal zones and of zones of earth radiation) showed) — when compared with results of preceding mortality investigations — that larvae especially prefered food corresponding to certain developmental stages. Also the directions est west had a distinct influence on the caterpillars migrations. Influences of the migrations by direction as well as by the available food were different in the ranges investigated (normal zone, zone of earth radiation, metal zone). The result was a migration behaviour in the zone of earth radiation and in the metal zone like a reflected image when compared to the normal zone in respect to direction, in the metal zone partlly also to the food sources.The zone of earth radiation was especially frequented by L₁ and also as place of pupation.Experiment of rearing caterpillars ofLymantria monacha encaged under Faraday Conditions showed that restricting of entering the electrical fields was of unfavourable influence on first instar larvae, but of favourable on elder ones. This ascertained former results, that electrical-magnetical powers are promoting the vitality of first, but restrict this of last developmental stages.Measurements for indirect registration of biophysical fields by means of cathode ray oscillograph are described.

---

---

Vortrag gehalten am Südtiroler Entomologentag in Dietenheim bei Bruneck am 21. September 1976.     

Intra- and inter-storm oxygen-18 and deuterium variations of rain,throughfall, and stemflow,and two-component hydrograph separation in a small forested catchment in Japan

Inter- and intra-storm oxygen-18 variations in rain, throughfall, and stemflow were measured to estimate accurate new water inputs to the watershed within a 0.84-ha watershed planted with 80-year-old Cryptomeria japonica and Chamaecyparis obutusa artificial forest at the Hitachi Ohta experimental watershed in Japan. In addition two-component hydrograph separation using oxygen-18 concentrations was conducted with four types of new water concentration: (1) incremental volume-weighted mean concentrations of rainfall; (2) constant concentrations of rainfall; (3) incremental volume-weighted mean concentrations of throughfall; and (4) constant concentrations of throughfall. Six storms from June to October 2000 were investigated. In the 26 July, 24 September, and 29 October storms, old-water percentages at the hydrograph peak were more than 56.4%, 66.6%, and 80.4%, respectively. In the 24 September and 29 October storms, the old-water contribution estimated by incremental volume-weighted mean concentrations of throughfall was the greatest. On the other hand, this was the smallest after the 26 July storm. Thus, by estimating the new water inputs more accurately, the old water contribution could be either large or small. In addition, there was a relative difference of about 5–10% between old water percentages calculated from the four types of new water. The uncertainty associated with the analysis of oxygen-18 concentrations was up to 4.8%. Thus the difference in estimates of new water affected the old water percentage more than the uncertainty of the two-component model itself.     

Zur Technik der Untersuchung von Erdbeerpflanzen und Chrysanthemenblättern auf Blattälchen (Aphelenchoides fragariae undA. ritzemabosi)

Zusammenfassung Die Befallsstärke von Erdbeerpflanzen durch Blattälchen wird allgemein in Älchen je 20 g Herzen ausgedrückt. Man versteht unter dem Herz einer Erdbeerpflanze die Knospe, die jungen Blütenanlagen und die unentfalteten Blätter. Es besteht aber ein gewisser Ermessensspielraum in der Zuordnung zu gefaltet bis zu voll entfaltet. Meist ist die Knospe am dichtesten befallen. Der Durchschnittsbefall sinkt deshalb um so tiefer, je mehr nicht zur Knospe gehörende Pflanzenteile mituntersucht werden. Es handelt sich um die Frischgewichte der Herzen. Diese unterliegen Schwankungen je nach Jahreszeit, Erdbeersorte und Witterung. Ferner sind die Herzen stark befallener Pflanzen leichter als die gesunder Pflanzen. Im Durchschnitt wiegen im Frühjahr 30 Herzen 20 g. Es wird vorgeschlagen, die veränderliche Bezugsgröße 20 g Herzen durch das konstante Maß 30 Pflanzen oder 30 Rosetten zu ersetzen.

---

Summary On the isolation of bud and leaf nematodes (Aphelenchoides fragariae andA. ritzemabosi) from strawberry and chrysanthemum. Part II.The degree of infestation to strawberry plants by the leaf and bud nematodes is usualy expressed in nematodes per 20 g hearts. The heart of a strawberry plant includes the bud, the young inflorescences and the young closed leaves. A certain degree of judgement is requirred to distinguish between a closed leaf and an opened one. As the nematodes are usualy most concentrated in the bud, the degree of infestation is brought down by the inclusion of parts of the plant that do not directly belong to the bud.The weight of the hearts is also natably affected by weather conditions, season and plant variety. Furthermore heavily infested hearts are lighter than healthy ones. In spring, 30 hearts weigh approximately 20 g. It is suggested that the unstable measure of 20g hearts be substituted by the more reliable amount 30 plants or 30 rosettes.

     

Einflüsse des Nährsubstrates auf die Insektizidempfindlichkeit vonDrosophila melanogaster (Meig.)

Zusammenfassung 19 verschiedene Nährböden wurden in ihrer Brauchbarkeit für Massenanzuchten vonDrosophila melanogaster Meig. getestet. Die Entwicklungsdauer der Larven unterschied sich auf den verschiedenen Substraten nur geringfügig, die Fliegenausbeuten waren aber sehr verschieden. Viele Tiere mit mittleren bis hohen Frischgewichten wurden besonders auf den Nährböden Göttingen, Bridges, Carnegie, Rußland und Freiburg erhalten.Die Schwankungen in der Empfindlichkeit gegenüber Parathion, DDT und Aldrin waren zwar nicht in jedem Fall richtungsgleich, doch zeigte sich, daß Taufliegen von den Substraten Japan, Synth. II, Synth. IV und etwas weniger auch von Kartoffel und Göttingen besonders empfindlich waren.Die Versuche zeigen, daß einheitliche Ernährungsbedingungen die Voraussetzung für den Vergleich verschiedener Testreihen sind.

---

Summary 19 different substrates have been tested for their utility for breeding flies in mass cultures. In each case the velocity of larval development was rather similar: the numbers of flies produced differed considerably.Flies bred on several half-synthetic media, as well as to a lesser degree on cooked potatoes, were especially sensitive to toxicants. The order of sensitivity to parathion, DDT, and aldrin was not always altered to the same degree. There was no clear correlation between the weight of the flies from different food and their sensitivities.The experiments demonstrate that standardized nutrition must be precluded to compare different test series.

---

Résumé 19 substrats nourriciers différents ont été l'objet de tests portant sur les aptitudes qu'ils offraient à la culture de colonies deDrosophila melanogaster. La durée de développement des larves ne présentait pas de différence sensible selon les différents substrats mais le nombre de mouches nées de ces cultures était très variable.Les mouches provenant de quelques substrats misynthétiques et de deux substrats de pommes de terre se montrèrent particulièrement sensibles aux insecticides. Cependant là encore les variations dans la sensibilité au parathion, DDT et aldrin n'allaient pas toujours dans le même sens.Les essais montrent que des conditions de nutrition homogènes supposent la comparaison de différentes séries de tests.

     

A contribution to the definition of the fiber saturation point

Summary There is hardly any term in wood science literature that has been defined so many times as the term fiber saturation point (FSP). In spite of this fact the discussion is still going on how to define and how to measure it. The aim of the paper is to evaluate some of the known definitions and propose a method of experimental measurement of FSP. The term cell wall saturation, in contrast with FSP, is clearly defined quantity that can be easily measured.The authors are grateful to the Slovak Grant Agency for Science for partial support of this work     

Über das Auftreten von Erdbeervirosen in Südspanien

Zusammenfassung In den Erdbeeranlagen der Sorte Tioga wurden mittels Blattpfropfung aufFragaria vesca alpina zwei Virosen ermittelt, die auf Grund der Symptome dem strawberry mottle = Erdbeervirus 1 zuzuordnen sind.Der Virusbefall des Ausgangspflanzgutes lag zwischen 4,1 bis 8,2 %, Er stieg im Anbaugebiet unter dem Einfluß einer intensiven Besiedlung durchPentatrichopus fragaefolii innerhalb eines Jahres von 65,2 % bis 69,6 %.Über den Test von Mutterpflanzen konnten inzwischen mehr als tausend virusfreie Stammpflanzen selektiert bzw. vermehrt werden. Die blattlausfreie Vermehrungslage in der Sierra Nevada ermöglicht die Fortfuhrüng einer virusfreien Erhaltungszucht.Die Ansteckungsrate kann in den Ertragsanlagen auf der Grundlage gezielter Blattlausbekämpfungen im Oktober/November sowie im Januar bis März erheblich gesenkt und damit praktisch bedeutungslos werden.

---

Summary Studies on viroses of strawberries in southern Spain After grafting strawberries of the sort Tioga uponFragaria vesca alpina two kinds of viroses belonging to the strawberry mottle group were observed. The primary attack amounted to 4.1–8,2%. Under the influence of the aphidPentatrichopus fragaefolii the attack rises to 65.2–69.6 %.More than thousand healthy plants were selected and multiplied. By this a plantation of healthy strawberries was settled in Sierra Nevada. Controlling measures against aphids in October/November as well as in January/March prevent the virus from enlarging on the plantation anew.

     

Auftreten und Bedeutung der Salatwarzellaus (Pemphigus bursarius [L.]) als Schäling an Kopfsalat

Zusammenfassung Die SalatwurzellausPemphigus bursarius (L.)(Aphidoidea, Pemphigidae) gehört wegen ihrer unterirdischen Lebensweise zu den schwer bekämpfbaren Schädlingen, die in Salatkulturen regional starke Schäden verursachen können und von zunehmendem Interesse sind. In einem Befallsgebiet in Wolfenbüttel bei Braunschweig werden daher mehrjährige Untersuchungen zur Ermittlung der Bedeutung und geeigneter Bekä mpfungsmöglichkeiten der Salatwurzellaus durchgeführt. Bisher können über das Auftreten und die Bedeutung dieses Schädlings folgende Aussagen gemacht werden: Es besteht kein ursächlicher Zusammenhang zwischen dem Auftreten der Salatwurzellaus und zweier Salatvirosen (Salatmosaikvirus und Gurkenmosaikvirus). Sie alle traten unabhängig voneinander auf. Im Untersuchungsgebiet überwintertP. bursarius ausschließ lich an Pappeln, nicht dagegen im Ackerboden oder an Wurzelresten. Die Anfälligkeit verschiedener Salatsorten gegenüberP. bursarius ist nach den bisherigen Ergebnissen an 30 Sorten recht unterschiedlich, wobei die Sorten Hilmar, Kordaat, Unico, Kloek, Viktoria und Winter Butterkopf einen geringen oder gar keinen Befall zeigten, während die Sorten Wunder von Voorburg, Kagraner Sommer und Winter Mombacher stark befallen wurden. Diese Versuche müssen weitergeführt werden, bevor eine abschließende Beurteilung möglich ist. Die Schäden durch die Virosen, speziell das Salatmosaikvirus, sind in den Salatkulturen wesentlich schwerwiegender als die durchP. bursarius verursachten Verluste. Über Bekämpfungsversuche wird später berichtet.

---

Summary The lettuce root AphidPemphigus bursarius (L.)(Aphidoidea, Pemphigidae) belongs to the difficult controlable pests because of their subterranean mode of life. In lettuce cultures of certain regions this aphid can cause serious damages and therefore it is of increasing interest. In an area severely attacked byP. bursarius at Wolfenbü ttel near Braunschweig investigations are going on for several years to get to know the importance of this insect and to find out appropriate possibilities for its control. Up to now the following statements can be made concerning the appearance and the importance of this pest: There is no causal association between the lettuce root Aphid and two viroses of lettuce (lactuca virus 1 and cucumis virus 2). These pests appear independent from each other. In the investigated areaP. bursarius does hibernate only on poplars but not in the soil or on remaining roots. According to the hitherto existing results of 30 lettuce sorts the susceptibility of the various sorts againstP. bursarius is very different. The sorts Hilmar, Kordaat, Unico, Kloek, Viktoria and Winter Butterkopf did show a low or no attack, during the sorts Wunder von Voorburg, Kagraner Sommer and Winter Mombacher were severely attacked. These experiments must be continued before a definitive decision is possible. The damages in the lettuce cultures caused by the viroses, especially by lactuca virus 1, are more serious than those caused byP. bursarius. The control experiments are reported later.

     

Ultrastructure—Critical domain for wood behavior

Summary That the behavior of wood in service results from its structure is generally accepted by wood scientists. No doubt this acceptance is due to the broad interpretation of such a term. Structure can refer to the organization of elements on a macro scale, such as in a laminated beam, as well as to the arrangement of cellulose molecules in the crystalline region of an elementary fibril.This presentation focuses on a structural domain that appears increasingly to be a critical one in wood behavior-ultrastructure. The spectrum of terminology that has been used in profusion during the electron microscopic era must first be defined so that confusion is minimized. Then a historical evolution of the field of wood ultrastructure can be presented to provide perspective. Structures that have been shown to affect or indeed to control certain processes can be identified. The role of a non-structure, the elusive transient capillary, can be illustrated. Microfibrillar organization and cell wall archictecture fall into the realm of ultrastructure as well.The past decade of research in wood science has been productive to a significant extent because of scanning electron microscopy and its accessory tools and techniques. The exploration of wood penetration by wood preservatives, pulping liquors and coatings using this approach has yielded much new evidence. One can speculate about the anticipated contributions of computer-driven SEM, stereology, STEM, and even higher resolution microscopy in the near future.     

Der Biotestnachweis von Insektiziden inColeus blumei mitDrosophila melanogaster M.

Zusammenfassung 1. Es wurden Hydroponikkulturen der Ziernessel mit 11 verschiedenen Insektiziden (Chlorierten Kohlenwasserstoffen, Phosphorsäureestern und Carbamaten) behandelt.2. Die Insektizide wurden bei bewurzelten und unbewurzelten Sprossen über die Nährlösung appliziert und nach verschieden langer Dauerkultur Extrakte von Blättern, Sprossen und Wurzeln auf ihre insektizide Wirkung im Biotest(Drosophila melanogaster) überprüft.3. Allgemein war die Kontaktwirksamkeit der Wurzelextrakte hoch, während Sproß- und Blattextrakte nur bei systemischen oder ähnlich wirkenden Mittein Wirkungen beobachten ließen. Hierbei erwies sich das Carbamat Isolan als besonders blattwirksam.4. Durch Vergleich mit Kontrollextrakten unbehandelter Pflanzen konnte eine unterschiedliche Maskierung der WS durch die Lipoide gezeigt werden. Blattlipoide waren erheblich wirksamer bezüglich der Abfangpotenz als Wurzelextrakte.5. Da jedoch diese Kontrollextrakte eine Eigentoxizität fürDrosophila beobachten ließen, wird die Beachtung solcher Störwirkungen gefordert und auch bei Modellversuchen, wie den hier angestellten, eine Reinigung der Extrakte vor den Biotesten vorgeschlagen.

---

Summary Bioassay with crude plant extracts(Coleus blumei) after basal treatment with insecticides in hydroponic culture resulted differenciated contact activity. 11 insecticides (and acaricides) have been investigated in commercial formulation (emulsion and wettable powder, application of different concentrations via mineral salt solution). Apical treatment with insecticides (spray- application) will be reported in later papers.Leaf, stem and root of isolatedcoleus developed contact reactions in extracts forDrosophila melanogaster M. (Rutshurel, sensitive and Göttingen, sensitive). Leaf-extracts after basic treatment with Isolan, Parathion, Diazinon, Demeton-o-methyl and Malathion caused high contact effects. Lower intensities are recovered in leaves after application (via roots) of Lindane and Trichlorphon (Dipterex®). Additions of DDT-formulations and Phenkapton are causing poisoning action of root extracts only and Chlorobenzilate was not effective onDrosophila. All other insecticides showing high poisoning in root extracts, resulted insecticidal actions in stem extracts regarding the degree of systemic properties. Thiodan is less active in that response than Lindane and the typical systemic substances as Isolan, Demeton-o-methyl etc.Some of the reactions could be regarded as well as action of the insecticidal substance as possible effect of formula. The bioassay of pesticides residues in crude extracts is serviceable under certain circumstances. It is proposed that better and more instructive information should be obtained by tracer-substances or by cleaning and separating procedures of the extracts (chemical methods) and subsequent bioassay.

     

Effect of collar insertion on soil respiration in a larch forest measured with a LI-6400 soil CO2 flux system

Little information is available on the effect of root cutting by the collar pre-insertion technique on soil respiration. In this study, we found that soil respiration rates decreased with increasing depth of collar insertion in both the with live roots intact and with live roots severed treatments, but the rate of decrease was substantially higher in the former. The cutting of roots, especially fine roots, may be responsible for this result.     

Fehlermöglichkeiten bei Rückstandsuntersuchungen von Gemüse und Obst- bedingt durch die Probenahme

Mistakes in the results of residue analysis in vegetables and fruits based on samples Mistakes in the results of residue analysis can be separated into mistakes of sample-taking and those of analysing. The mistakes of sample-taking can be avoided when the sample represents the contents of the whole material which is to be analysed in percent. But this is an ideal case.In two examples, lettuce and leek, it is demonstrated that the pesticides are not in the same amount distributed at the different zones of the plant, the differences in the amounts can be, in the case of lettuce after application of quintozene, more than a fourtyfold amount or, in the case of leek after application of mancozeb, a twentyfold amount. Furthermore, the residues can be different from one plant individual to another demonstrated at cherries and radishes. The differences may be caused either by different application techniques or, for example, by different weight of individuals of the same species. Also, different habitus and growth can lead to different residues from one plant individual to another. When the plants take up the pesticides from the soil, a different pesticide distribution in the areas of the soil can also give rise to different residue values.Therefore, the man (engineer or analyst) who takes the samples, must take care for:1. taking the samples symmetrically from the field or from bottom to top of the trees2. chosing those plant individuals to give the labour sample which represent the average weight and the average habitus of the individuals. If plant individuals are analysed which take up the pesticides from the soil, the area from which the sample is derived, must be given.From all points shown, there is clear that a range of disseminating values which can be more than 100% must accounted in the values of residue analysis.     

Physiological and psychological responses to a heavy floor-impact sound generated by dropping an automobile tire in a wooden house

We investigated the physiological and psychological responses of ten healthy male volunteers to a single heavy floor-impact sound generated by dropping an automobile tire from heights of 50, 100, and 150cm in a wooden house. Blood pressure and peripheral blood flow were measured simultaneously, and sensory evaluation was conducted using the semantic differential method. The results obtained were as follows: (1) the systolic blood pressure increased and the peripheral blood flow decreased when the subjects heard the heavy floor-impact sound; (2) the heavy floor-impact sound caused the subjects to feel uncomfortable, but there was no significant change in sharp and monotonous feelings; and (3) for the heavy floor-impact sound for 100cm and that for 150cm, the subjects showed no difference in comfortable feeling, but we detected differences in the variations of both the systolic blood pressure and the peripheral blood flow.Part of this research was presented at the 48th Annual Meeting of the Japan Wood Research Society, Shizuoka, April 1998.     

Beitrag zur Epidemiologie und Biologie des BuchenspringrüblersRhynchaenus (Orchestes) fagi L. an Obstgewächsen

Zusammenfassung Im Jahre 1963 wurde in verschiedenen Gebieten Deutschlands ein Massenauftreten des BuchenspringgrüßlersRhynchaenus (Orchestes) fagi L. beobachtet. Die Jungkäfer gingen ab Mitte Juni an Obst über und verursachten dort große Schäden. Bevorzugt wurden Aprikosen, Süßkirschen und Äpfel der Sorten Cox Orange, Golden Delicious und Goldparmäne, wä hrend Ontario nicht befallen war.In Rheinland-Pfalz wurden noch Ende Oktober agile und lebhaft fressende Käfer in großen Massen selbst an lagerndem Obst beobachtet.Im Frühjahr 1964 wurden in Rheinland-Pfalz erneut Massen von Altkäfern in Buchenbeständen beobachtet. Die Jungkäfer schädigten außer Obst auch Beta-Rüben.In künstlichen Zuchten konnten lediglich 8 von Hundert der Versuchstiere überwintert werden.Zur Bekämpfung erwiesen sich Kontaktinsektizide auf Lindan-DDT-Basis den Phosphor-Estern überlegen.

---

Summary In 1963 an enormous appearance ofRhynchaenus (Orchestes) fagi L. was observed in many parts of Germany.The young beetles attacked fruits in the second part of June. Apricots, cherries and especially the apple varieties Cox Orange, Golden Delicious and Goldparmaine were most severe damaged. Only the variety Ontario remained unattacked.Observations in Rhineland-Palatinate proved thatRh. fagi attacked apples still in October even at store houses.During the spring 1964Rh. fagi attacked beech-trees and fruits once more and even beets.Kept in special assays only 8 percent of the caged beetles survived the winter.In experiments for controllingRh. fagi proved more susceptible to Lindane-DDT and less susceptible to parathion and diazinon.

---

---

Meinem verehrten Lehrer, Herrn Professor Dr. Hans von Lengerken zum 75. Geburtstag gewidmet.