장음표시 사용
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minance, dominant individuals should de part with higher fat loads is dominanceis associaled with age and a higher fat deposition. During their autumia migration, Sed ge Warblers attain hi glier sat depositionrates clo se to their main prey the aphid S malo 'teris Pruni BIBBY et a l. l9J6.
abundance in solitheria Britain and northeria France, the aphid populations os solitheria Europe will have at ready peaked and decreased in si Ze by the time of the Sed ge Warblers' autumia migratory passage. As should be expected where fatdeposition rate and migration speed decrense along the rotite, these warblers deposit extreme ly large sat loads in solitheria England and nori heria France and may
Sed ge Warblers was expressive, aphids occurred in smali number in the autumnmigration season. According to brief observation, these in secis are abundant in
Achnowlei emeritS - we wish to express our gratitude to the members of the Hungarian Ornithological and Nature Conservation Society who hel ped in the sield work. The research was sponsored by Foundation os Pro Renovanda Cultura Hungariae.
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MAHUNKA, S. and L. MAHUN A-PAPPThe authors had the opportunity for years to study the Oribati dspecies described by Berlese currently deposited in the Istituto Sperimentale per la Zoologia Agraria at Florence. The resultS of this series of studies are SummariZed in this Volume. The volume begins with an essay- like Introduction heaVily re-lying on subjecti Ve opinions discussing the generat questions of Oribaiology. The following section lisis Berlese's species placed in the modern System helping the specialisis with morphological notes and many dra ingS: here also the condition of the specimensis discussed and lectotypes are deSignated. The third, large Section is the catalogue proper, Wherein ali the species are listed in the systematic order together with their combi nation and synonymic names. Here orae may find ali the literature data, USU atly miSSing froni ordinary works, with referetice to Description and Taxonomy, Distribution, with Spectat emphasis ora CatalogueS WhΟSe references are partly unreliable. Where it was dee med necessary further information are added under the headingos Remarks. The volume closes with a very detailed list os lit
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Actia Mologica Academiae Scientiarum Hungaricae 42 s.). Po. 28I 87. I996
A COMPARI SON OF EXTRACTION METHOD SOP PREE-LIVINO TERRESTRIAL NEMATO DES
Concerning total numbers os extracted nematodes, the decantation and cotton wool si iter technique and the OOSTEN BRlNK elutriator were the most essective. These twO techniques canabsolutoly be recommended sor use, the choice belween them should depend on the experimental prosile and the sinanciat sotirces os a gi ven laboratory. SEINHORSVs two fiasks method also gave significantly higher resulis than other lwo techni ques tested. Resulis obtained by BAERMANN-sunneis were comparabie to other methods only in ternas os relative proportion os extracted Mononchida. Concerning any Other parameter. BAERMANN-sunnel technique gave much poorer resuli S. Key wOrds free-li ving terrestriat nematodes. extraction methods, efficiency
Free-li ving ne matodes are an imponant grotis' os soli biota. Their handi ingraises severat problenas and alternative methods of different efficiency frona sana pling to identification S'JACOB and van BEZOOlJEN l 984. SOUTHEY l9J0). An important issue is the difficulty of their extraction frona soli sample s. During the past few decades a great amount of data has been collected and severat re-vie w articles have been publis hed on the topic os ne matode extraction frona solis amples se. g. HARRISON and GREEN l9J6. MCSOR LEY and WALTER l99l. OOS TENERIN K l 960. OOSTENARI NK l9JO. TOBAR Jl MENEZ l 963. VI CLIERCHIO and SCHMITT l 983). There is not a single method to extraci the whole ne matOdefatina frona a soli sample due to the large variabili ty of nematode taxa; their be-havi our and different physical properties of their habitats. V lGLIERCHIO and SCHMITT l 983) concluded 'It should he rea lily apparent that current extracti Onmethodology is in urgent need of substantiat improve ment to achie Ve near quantitative status. V Stili, it is necessary to test avat labie and generat ly accepted meth ods in order to learn more abolit their characteristic s. The objective of this study was to determine the efficiency of sive extraction techni ques with respect to the total number of extracted ne mutodeS, qu In
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tities of ne matodes be longing to certa in taxonomic or functional groups, and the irrelative proportions to the total numbers of extracted ne matodes.
todes cara be obtai necl. Aster counting nematodes extracted with this method. their numbers were multiplied by two in order to obtain an estimation comparabie to l00 mi soli samples used in other techniqUOS. Extracted nematodes were counted under a stereo microscope s50 X magnification), in transmitted light. Absolute and relative numbers os ne matode groups were used to compare the extractiontechni ques, such as the total number os extracted ne matodes by each technique . number of ne ma-todes be longing to certain taxonomic or stinctional groups. and their relative proportions to the totalnumbers. The taxonomic or functional groups were: plant sine ling nematodes of the ordor Tylenchida fas Piarestylen Chus Spp., PratylenchuS Spp. and RotylenchuS Spp. occurring in the extracted fam-ples), fami ly Tricho loridae including virus transmitting plant ne matodes, and ordor Mononchida containing slow-moving relatively large predators). The rest os the extracted ne matocles were categori Zed in one group as mi Scellaneotis ne matodes. This category was necessary due to the applied counting technique. that e nabled a rapid scimen ing of the extracted ne matodes hut masked delatis in the taxonomic composition of the Samples. As a statistical analysis. MANN-WHITNEY's U-test was perlii med to compare the medianvalues of ne malo te numbers obtained with disserent techni ques.
Means and standard deviation values for the ne malo te groups extracte lusing the different methods are gi ven in Table l. The data show that resulis frona the B AER MANN-mnia et technique were much lower than ali the other method s.
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FREE LIVING TERRESTRIAL NEMATODE EXTRACTION METHODS
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Tahle 3. Significance of differesaces in numbers of the two main groups of nematods extracted with different methods. Upper right triangle represenis the values for tylenchids. lower len Onethose for miscellaneotis). MANN-WHITNEY U-test - NS α non significant differe iace α ΡαβR
Among widely used methods the BAERMANN-funnet is considered to bequic k less laborious and inexpensive MCSORLEY and WALTER l99 l); generat lyresulting in a fairly clear final suspension whicli is necessary for the counting of nematodes. MoreoVer iis water consumption is very low compared to the other techni ques. On the other hand this is a probab ly less efficient method. Presentdata indicate that in nearly original forna iis efficiency is poor, only the relative proportion os certain groups like Mononchida) can he comparabie to other tech nique s. The low value os extracted tylenchids cala be due to the flower move mentos these animais compared to sonae hacteriai feeding nematodes. In addition theoriginal conditions of the B AER MANN-funnel technique do not ei duce ne matodesto leave the mass of the soli during the extraction proces s. This may be e speciallytrue for main ly plant-Decling tylenchids, whose movement is orientaled by plantexudates to a considerable extent GREEN l9 Pl). There are severat modifications that can be used to improve the resulis obta ined by the B AER MANN-funnel technique ANDERSON and COLEM AN l9JJ. NAGY l99β. ROB INSON and HEALD l 989. SOHLENIUS l9JJ). Through the controlof certain factors smali sample siZe and th in layer of Soli, proper Oxygen Supply, temperature gradient, longer extracti On period) a more accurate estimation os ne-matode fauna in a gi ven soli sample may be achi eved. Thus this method is fre
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FREE-LIVINC TERRESTRIAL NEMATODE EXTRACTION METHODS
Vantages as well. like reason able water consumption fairly clean final suspensionand easy separability of nematode siZe-classes, this method is stili popular amon gnemato logi sis J. V. BEZOOIJEN, perS. Comm.)Although the B AER MANN-funneis and COBB's method were in thenaset Vestes s effective than the rest, in combination with other extraction techni ques their
application can stili he effective VAN GUNDY l 982. VIGLIERCHIO and SCHMITT
io reco Ver SOmewhut more ne matocles froni comparabie soli type at the presents ample si Ze, than the decantation method and the OOSTENERI NK elutriator. However, he admitted that in other parameters sas required time os extraction, constance in yielded ne matodes, clearnes s of final suspension) the decantation technique and especialty the OOSTEN BRIN K elutriator was preferable . In the present stud y the decantation and cotton wool filier technique and the OOSTENERIN K elutriator are significantly more effective than any other extraction method tested. However, differences observed in their efficiencies arenei ther so big nor so obviolis that any of them could be recommended exclusive-ly. When making a choice between them, one has to consider the low cosis and the simplici ty of the decantation and cotton wool fit ter technique versus the high expenses of the OOSTENERIN K elutriator. On the other hand the lalter technique has rem arkable ad Vantages, like higher resistance to personal imbalances, usual lycleaner final suspension, sultability for simultaneotis application. These differen-ces can he decisive depending on the experimental profite of the laboratory.
AC Howle gementa - The present experiment was made possibie through a student mobili typrogram belween the wageningen and Godolio Agricultural Universities. The author is gratem l to 4r. J. I. S'JACOB and Mr. J. VAN BEZOOIIEN sWAU. Departinent of Nematology) for teaching the basi cs of handi ing nematocles sincluding various extraction methods) and for their hel psul altitudewhile staying in Wageningen. Also thanks are due to Prof. GABOR BARONYI sor his hel p in data processing and his use sui comments during preparation the manuscript .