Studies on population frequency of insects and mites causing galls on the leaves of the European aspen<Emphasis Type="Italic"> Populus tremula</Emphasis> L. in southern Poland

Species composition of galls on the leaves of Populus tremula L. was studied in 2002–2003 in two localities: the Ojców National Park and the Andrychów Forest District. A total of 2,199 galls were found, 1,522 of which were found in 2003. The galls were caused by ten insect or mite species. The species composition of the galls was similar in these two consecutive years. Phyllocoptes populi (Nalepa) was the most abundant species in both areas in 2003. The index of occurrence frequency (F) value was highest in the case of P. populi, namely 0.280 in the Ojców NP (2003), and lowest , i.e. 0.00002, for Trichiocampus grandis (Lepeletier) at both sites in 2003, and for Contarinia petioli (Kieffer) in the Ojców National Park in 2002. The highest value for Agrells index of species co-occurrence , i.e. 0.944, was found for Harmandia cavernosa (Rübsaamen) and H. tremulae (Winnertz) (Ojców NP, 2002), and the lowest (0.050) for T. grandis and H. globuli (Rübsaamen) (Ojców NP, 2003).     

Studies on insects and mites causing galls on the leaves of lime treeTilia cordata Mill. in the Ojców National Park in Poland

Analytical studies were conducted on the species composition of galls occurring on the leaves ofTilia cordata Mill. in the Ojców National Park in 1997–1998. The species composition of galls was identical in two years. Galls were caused by 6 species. The most numerous species wereEriophyes leiosoma (Nalepa) in 1997 andPhytoptus tetratichus tetratrichus Nalepa in 1998. Index of occurrence frequency and Agrell’s index of species co-existence have been calculated. This index reached the highest values in both years in case ofE. leiosoma andP. tetratrichus tetratrichus.     

Studies on insects and mites causing galls on the leaves of European aspenPopulus tremula L. in the Ojców National Park in Poland

Analytical studies were conducted on the species composition of galls occurring on the leaves of European aspen Populus tremula L. in the Ojców National Park in 1997–1998. The species composition of galls was similar in two consecutive years, i.e 6 and 7 species, respectively (a total of 5492 galls). The most numerous species wasPhyllocoptes populi Nalepa in both years. Index of occurrence frequency and Agrell’s index of species co-existence have been calculated. This index reached the highest values in both years in case ofHarmandia cavernosa (Rübsaamen) andH. tremulae Winnertz.     

Studies on insects causing galls on the leaves of pedunculate oak Quercus robur in southern Poland

Analytical studies concerning the species composition of galls occurring on the leaves of Quercus robur L. were conducted in 2000 in three localities: near an urban agglomeration of Kraków – the Wolski Forest, in a protected area – the Ojców National Park and in a managed forest – the Andrychów Forest District. In each of the selected localities 2000 leaves (a total of 6000 leaves) were randomly collected. A total of 2246 galls, including 1028 in the Andrychhów FD, were found. The galls represented 12 insect species. The species composition of galls in the Ojców NP (11 species) distinctly differed from those of the remaining two areas (7 species each). Neuroterus quercusbaccarum (L.) ♀♀ was the most abundant species in the managed forest. The index of occurrence frequency and the Agrell's index of species co-existence have been calculated. The frequency of gall occurrence varied considerably in the investigated localities. On the basis of the Agrell's index of species co-existence it was shown that the strongest bond existed between Neuroterus laeviusculus Schenck ♀♀ and Andricus ostrea (Hartig) ♀♀ in the managed forest.     

Studies on insects and mites causing galls on the leaves of hornbeamCarpinus betulus L. in the Ojców National Park in Poland

Analytical studies were conducted of the species composition of galls occurring on the leaves ofCarpinus betulus L. in the Ojców National Park in the years 1995–1996. Galls were caused by 3 species:Aceria macrotricba (Nalepa),Zygiobia carpini (F. Löw) andZ. ruebsaameni Stelter (a total of 631 galls). Index of occurrence frequency and Agrell's index of species co existence have been calculated.Z. ruebsaameni appeared to be a new species for the fauna of Poland.     

Studies on insects and mites causing galls on the leaves of elm Ulmus laevis Pall. in the Mogilski Forest in southern Poland

Species composition of galls on the leaves of Ulmus laevis Pall. was analysed in 2001?–?02 in the Mogilski Forest – near an urban agglomeration of Kraków. A total of 5830 galls were found. The galls were caused by 5 insect or mite species. Aceria ulmicola brevipunctata (Nalepa) was the most abundant species in both years. The index of occurrence frequency and Agrell's index of species co-occurrence have been calculated. The index of occurrence frequency (F) reached the highest value in the case of A. ulmicola brevipunctata, namely 1.740, in 2001, and the lowest value, i.?e. 0.00?005 for Schizoneura ulmi (Linné), in 2001. Agrell's index of species co-occurrence reached the highest values, i.?e. 0.500, in the case of A. ulmicola brevipunctata and Physemocecis ulmi (Kieffer), in 2002, and the lowest one, namely 0.050 for A. ulmicola brevipunctata and Schizoneura ulmi, in 2001.     

Relationships between the number of dwarf shoots of<Emphasis Type="Italic"> Larix decidua</Emphasis> Mill. damaged by different insect species in the Ojców National Park in southern Poland

A study was conducted on the interrelationships between the number of dwarf shoots of Larix decidua Mill. damaged by insects: Adelges laricis Vall. Coleophora laricella Hbn., Spilonota laricana Hein. and Dasineura kellneri (Hensch.). The study made use of dwarf shoots collected at three sites in the Ojców National Park, southern Poland during 2002–2003. A total of 240 branches with 19,239 dwarf shoots, collected from 60 larches were designated to the study. The data obtained were subjected to statistical analysis using the Spearman rank correlation coefficient and the Students t-test at the 0.05 level. No unequivocal correlation was found between the relationships.     

Studies on insects and mites causing galls on the leaves of common ash <Emphasis Type="Italic">Fraxinus excelsior</Emphasis> L. in the Ojców National Park in Poland

The occurrence frequency of galls caused by insects and mites on the leaves of Fraxinus excelsior L. was investigated, based on leaf samples collected in the Ojców National Park in 2000?–?2001. The species composition of galls was identical in two consecutive years. Galls were caused by 5 species a total of 2881 galls. The most numerous species was Dasineura fraxinea (Kieffer) in both years.Index of occurrence frequency and Agrell's index of species co-existence have been calculated. This index reached the highest values in case of Dasineura fraxinea and Vasates fraxini (Nalepa) in 2000 as well as D. fraxinea and Psyllopsis fraxini (L.) in 2001.     

Studies on insects and mites causing galls on the leaves of sycamore mapleAcer pseudoplatanus L. in the Ojców National Park in Poland

Analytical studies were conducted of the species composition of galls occurring on the leaves ofAcer pseudoplatanus L. in the Ojców National Park in the years 1994–1995. The species composition of galls was similar in both years. The most numerous species wereAceria pseudoplatani (Corti) andDasineura vitrina (Kieff.) in 1995. Index of occurrence frequency and Agrell's index of species co-existence have been calculated.     

Management of<Emphasis Type="Italic"> Meloidogyne incognita</Emphasis>, the root-knot nematode,on soybean as affected by marigold and sea ambrosia (damsisa) plants

Marigolds (Tagetes erecta and T. patula) or sea ambrosia (Ambrosia maritima) as intercropped plants with soybean (Glycine max) cv. Giza 21 infected with Meloidogyne incognita, the root-knot nematode, significantly (P0.05 and 0.01) reduced nematode numbers on soybean as indicated by the percentage reduction of galls, developmental stages and egg masses in roots and juveniles (J2) in soil. Marigolds significantly (P0.05 or 0.01), in most cases, increased plant growth parameters of soybean, but sea ambrosia had an adverse effect on plant growth parameters. Addition of chopped green leaves of sea ambrosia to the soil planted to soybean significantly (P0.05 and/or 0.01) reduced M. incognita reproduction and development. Sea ambrosia also had an adverse effect on soybean plant growth.     

Insect inhabitants of old larval galleries of<Emphasis Type="Italic"> Saperda populnea</Emphasis> (L.) (Coleoptera: Cerambycidae) in Bulgaria

The complex of insect inhabitants of old larval galleries of Saperda populnea (L.) (Coleoptera: Cerambycidae) was studied during the period 2000–2003 in 18 localities in Bulgaria. As a result, 32 insect species were reared from old S. populnea galls: Metopoplax origani (Kolenati) (Heteroptera: Lygaeidae), Malachius sp. (Coleoptera: Malachiidae), Agrilus pratensis pratensis (Ratzeburg) (Coleoptera: Buprestidae), Xylocleptes bispinus (Duftschmidt) (Coleoptera: Scolytidae), Crossocerus cetratus (Shuckard), Crossocerus megacephalus (Rossi), Crossocerus nigritus (Lepeletier & Brullé), Crossocerus acanthophorus (Kohl), Passaloecus brevilabris Wolf, Passaloecus gracilis (Curtis), Psenulus schencki (Tournier), Solierella compedita compedita (Piccioli), Trypoxylon figulus figulus (Linnaeus), Trypoxylon fronticorne fronticorne Gussakovskij (Hymenoptera: Crabronidae), Cleptes schmidti Linsenmaiser, Trichrysis cyanea (Linnaeus) (Hymenoptera: Chrysididae), Clistopyga incitator (Fabricius), Ctenochira sanguinatoria (Ratzeburg), Liotryphon crassisetus (Thomson), Nemeritis fallax (Gravenhorst), Mesochorus georgievi Schwenke, Campoletis sp. (Hymenoptera: Ichneumonidae), Charmon extensor (Linnaeus) (Hymenoptera: Braconidae), Eupelmus urozonus Dalman (Hymenoptera: Eupelmidae), Perilampus aeneus (Rossius) (Hymenoptera: Perilampidae), Trichiocampus grandis (Lepeletier) (Hymenoptera: Tenthredinidae), Janus luteipes (Lepeletier) (Hymenoptera: Cephidae), Cydia corollana (Hübner) (Lepidoptera: Tortricidae), Fiebrigella brevibucca (Duda) (Diptera: Chloropidae), Eustolomyia hilaris (Fallén) (Diptera: Anthomyiidae), Senotaina sp. (Diptera: Sarcophagidae) and Heringia vitripennis (Meigen) (Diptera: Syrphidae). Amongst them, 27 species were established as new inhabitants of old S. populnea galls. Five species (C. schmidti, N. fallax, M. georgievi, P. aeneus and J. luteipes) were recorded for the first time in Bulgaria. The dwellers of old S. populnea galls belong to the following ecological groups: insects using galls as a place to develop (3 species); insects nidificating in empty galls (10 species); insects using old galls as a pupating place (1 species); insects using empty galls as overwintering shelters (3 species); predators and parasites of primary dwellers of empty galls (13 species); or insects with uncertain ecological status (2 species).     

Dihydroroseoside, a new cyclohexanone glucoside, from the leaves of shirakamba (Betula platyphylla Sukatchev var.japonica Hara)

A new cyclohexanone glucoside (II) and a known cyclohexenone glucoside roseoside [I, (6S, 9S)-6-hydroxy-6-(9--D-glucopyranosyloxy-trans-7-butenyl)-1,5,5-trimethyl-1-cyclohexenone] were isolated from an ethanol extract of shirakamba (Betula platyphylla Sukatchev var.japonica Hara) leaves. The structure ofII was determined to be (6S, 9R)-6-hydroxy-6-(9-O--D-glucopyranosyloxy-trans-7-butenyl)-1, 5,5-trimethyl-1-cyclohexanone by¹H-NMR and¹³C-NMR spectroscopic analyses. It was named dihydroroseoside.     

A study on some anatomical parameters of the piercing-sucking process in leaves and branches of<Emphasis Type="Italic"> Pittosporum tobira</Emphasis> L. (Pittosporaceae) infested by the cottony cushion scale,<Emphasis Type="Italic"> Icerya purchasi</Emphasis> Maskell (Homoptera: Coccina,Margarodidae)

Pittosporum tobira L. (Family Pittosporaceae) is an important plant species grown in parks and gardens in Turkey. The cottony cushion scale, Icerya purchasi Maskell (Homoptera: Coccina, Margarodidae), is an important pest of P. tobira, and causes damage mainly to the leaves, branches and stems of the host plant. In spite of the great economic importance of I. purchasi to its host plant P. tobira, information has been limited on some basic anatomical parameters of the nature of the damage to leaves and branches. The present study was, therefore, initiated to investigate the insertion and penetration of stylets into the leaves and branches of P. tobira, the length of stylets and depth of penetration in both of these tissues, and penetration of stylets into the cortex, xylem and phloem tissues and into the secretory and non-secretory canals of the leaves and branches. The results showed great variations between the leaves and branches in all the criteria observed in I. purchasi infesting P. tobira. The study found 20 whole and 23 broken mouthparts in the leaves as compared to 3 whole mouthparts and 1 broken in the branches. Length of the stylets inserted into the leaves ranged from 33.83 m to 540.93 m and into the branches from 202.85 m to 340.8 m. The stylets reached greater depths in the leaves, at 540.93 m, as compared to 498.67 m in the branches. The stylets in the leaves were associated with 12 secretory canals, but with none in the branches. It was found that three stylets reached xylem in the leaves as compared to one in the branches. Similarly, 17 stylets in the leaves reached to the phloem, but only 2 in the branches. No stylets were found in the cortex of the leaves, but one was found in the branches. In the leaves, 11 stylets reached and remained in the non-secretory canals, but none in the case of the branches.     

Genetic diversity ofKandelia candel andBruguiera gymnorrhiza in the Southwest Islands, Japan

The genetic diversity of the mangrove tree speciesKandelia candel andBruguiera gymnorrhiza in the Southwest Islands of Japan was investigated. These islands are located at the periphery of the distribution area of the two species, and their populations are relatively small. Allozyme analyses of 17 loci inK. candel and 13 loci inB. gynmorrhiza revealed very little genetic variation in both species. At the species level, the proportion of polymorphic loci was 4.2%, the average effective number of alleles per locus was 1.02, and the average expected heterozygosity was 0.012 inK. candel. The corresponding figures forB. gymnorrhiza were 9.0%, 1.06 and 0.035, respectively. However, the coefficients of genetic differentiation among the populations were high (G _ST=0.165 forK. candel and 0.253 forB. gymnorrhiza). The genetic variation and habitat area ofK. candel on Amami Island is greater than on the islands Okinawa and Iriomote. The genetic variation and habitat area ofB. gymnorrhiza is greater on Iriomote Island than on the islands Okinawa and Amami. The level of genetic variation in both of the species might be related to their population sizes.     

Decomposition and nutrient release from leaves,twigs and roots of three alley-cropped tree legumes in central Togo

The decomposition of leaves, twigs and roots of two diameter classes (<1.5 mm, 1.5–5 mm) were examined in an alley cropping experiment withGliricidia sepium, Calliandra calothyrsus andSenna sianea in the subhumid savanna of Central Togo using the litterbag technique. The effect of the application of leaves and twigs as mulch or green manure was examined. Gliricidia showed the most rapid mass loss. For all species, leaves decomposed faster than roots. Twigs had the lowest decomposition rate except forCalliandra. The two diameter classes of roots decomposed differently in the three species:Gliricidia fine roots decomposed faster than its coarser root fraction, the coarse roots ofSenna decomposed faster than the fine roots.Termites influenced the mass loss of twigs and roots to varying extents for the different species. In the case of twigs this was markedly influenced by the mode of application: green manure showed more termite frass than mulch.Nutrient release resembled the mass loss patterns of the prunings except for K, which was leached independently from mass loss. The release of the different nutrients was in the order CaGliricidia andSenna seemed to be best for mulch and green manure production at our site.     

The performance of the leaf mulches ofLeucaena leucocephala,Flemingia macrophylla andGliricidia sepium in weed control

The performance of the leaf mulches ofLeucaena leucocephala, Gliricidia sepium andFlemingia macrophylla in weed control has been tested in two trials. The length of the period during which a mulch layer yields significantly less weedbiomass compared to the control plots is called the effective life-span of the mulch.Of the three mulch materials only that ofF. macrophylla shows promise in retarding weed development.In the second trialF. macrophylla leaf mulch was applied at rates of 3, 6 and 9 tons dry matter per ha. The effective lifespan of a mulch layer of 3 tons is between 12 and 13 weeks. The treatments 6 and 9 tons have effective life-spans of over 14 weeks.For moderate quantities (up to 5 tons of dry leaf mulch per ha) the effective life-span is estimated at about a 100 days.The value of mulching in weed control is limited to the control of weed species that multiply by seed. Regrowth originating from roots or stumps from former vegetation is unlikely to be checked by a mulch layer.The subject of this paper is part of a broader study, presently conducted in Southern Ivory Coast, on the production, agronomical value and use in alley-cropping systems of the species mentioned in the title of the paper. A final report is scheduled for publication in 1988.     

Comparative study on drought resistance ofLarix olgensis Henry andPinus sylvestris var.mongolica (I)

Water potential (ϕ w) and net photosynthetic rate (Pn) ofLarix olgensis andPinus. sylvestris var.mongolica decreased with the decrease of soil water content. ϕ w and Pn ofL. olgensis changed hardly during the first 9 days after stopping watering, then decreased sharply at the 10th day Pn ofP. sylvestris varmongolica decreased slightly during the first 8 days, then decreased sharply at the 9th day. Their respiration rate, chlorophyll content and their a/b ratio changed hardly. The following 3 conclusions were obtained and discussed exhaustively. (1) ϕ w can be used to direct watering as a sensitive index of judging whetherL. olgensis andP. sylvestris var.mongolica lacking water. (2) The decrease of Pn ofL. olgensis andP. sylvestris var.mongolica when drought had nothing to do with chlorophyll. (3)P. sylvestris var.mongolica had morphological drought resistance, while Lolgensis had physiological drought resistance, and their drought resistance was discussed comparatively first time.     

Interactions between<Emphasis Type="Italic"> Orthotomicus erosus</Emphasis> (Woll.) (Col., Scolytidae) and the Argentine ant<Emphasis Type="Italic"> Linepithema humile</Emphasis> (Mayr) (Hym., Formicidae)

Interactions occurring between Orthotomicus erosus, an economically important pine bark beetle in Portugal, and the aggressive Argentine ant Linepithema humile were investigated. Tri-trophic experimental enclosures consisting of Pinus pinaster logs, O. erosus adults and L. humile workers were set up in the field and in the laboratory. Interactions between ants and scolytids were observed and quantified in terms of the bark beetles success in colonizing the logs. The presence of L. humile did not influence the ability of O. erosus to colonize the logs, apparently due to the difficulties met by the ants in handling the bark beetles and to their inability to injure them. Thus, although abundant in many pine stands in Portugal and in spite of its aggressiveness, L. humile does not seem to affect populations of O. erosus.     

Influence of host plant species of Bemisia tabaci (Genn.) (Hom., Aleyrodidae) on some of the biological and ecological characteristics of the entomophagous Serangium parcesetosum Sicard (Col., Coccinellidae)

The entomophagous Serangium parcesetosum Sicard (Col., Coccinellidae) is an effective predator of some whitefly species. However, information on the influence of the preys host plant species on its biological and ecological characteristics is still lacking in the literature. Therefore, the current study focuses on the possible influence of three greenhouse and two field host plant species of Bemisia tabaci (Genn.) (Hom., Aleyrodidae) on the number of eggs laid by S. parcesetosum. In addition, because of the economic importance and widespread planting of cucumber in greenhouses and cotton in the field, these plants were selected for further investigation into the development, mortality, longevity and reproduction of S. parcesetosum at a high temperature in the laboratory. Results showed that S. parcesetosum was able to lay eggs on all five host plant species of B. tabaci, whether greenhouse or field plants. However, among the three greenhouse plant species studied, S. parcesetosum females laid the highest number of eggs on cucumber followed by tomato and then sweet pepper. Of the two field plant species, significantly higher numbers of eggs were laid on tobacco than on cotton. S. parcesetosum could develop either on cucumber or on cotton as preferable host plant species for B. tabaci. There were significant differences in mean developmental duration of larval instars of the same sex between both host plant species; the duration was significantly shorter on cucumber than on cotton. There were no significant differences for mean total developmental duration from egg to adult emergence between both host plant species within the same sex; females showed a mean of 15.9 days and males of 15.1 days on cucumber, while on cotton the means were 17.2 days for females and 16.2 days for males. Total mortality percentage of S. parcesetosum during development from egg to adult stage was lower on cucumber than on cotton, 20.6 and 23.8%, respectively. Longevity of S. parcesetosum varied according to host plant species and sex with a mean of 63.4 days for females and 50.3 days for males on cucumber, and 92.4 days for females and 52.5 days for males on cotton. On cucumber, mean period of oviposition of S. parcesetosum was significantly longer than on cotton. Mean total fecundity was significantly higher on cucumber than on cotton, with means of 97.7 and 31.0 eggs/female, respectively.     

Comparison of terpenes in extracts from the resin and the bark of the resinous stem canker of Chamaecyparis obtusa and Thujopsis dolabrata var. hondae

A monoterpene and 15 diterpenes were isolated from the ethyl acetate extracts of the bark-glued resin from the resinous stem canker ofThujopsis dolabrata var.hondae Makino. A monoterpene (nezukone20) and 4 diterpenes (acetyl torulosol5, acetyl isocupressic acid8, acetyl abietinol11, and 7-methoxytotarol18) were characteristic constituents of the ethyl acetate extracts but were absent in then-hexane extracts from the resinous stem canker ofT. dolabrata var.hondae. These terpenes were first isolated fromT. dolabrata var.hondae andT. dolabrata. The available literature suggests that diterpene18 is a new compound. The resinous stem canker ofChamaecyparis obtusa Endlicher contained larger amounts of manool1,trans-communic acid6, and ferruginol12 and smaller amounts of isocupressic acid7 and abietinol10 than the resinous stem canker ofT. dolabrata var.hondae. The concentration of18 was less than 2% in the extracts, and the resinous stem canker ofC. obtusa lacked this compound. The resinous stem cankers ofC. obtusa andT. dolabrata var.hondae provided extracts 15.6 and 4.96 times, respectively, heavier than the healthy ones. Large differences in the ratios and compositions of terpenes were also observed between the resinous stem canker and the healthy trees. Terpenes isolated from the extracts contained many kinds of diterpene, especially the labdane-type diterpenes, in these diseased trees. These results suggest that the presence of labdane-type diterpenes is closely associated with the resinous stem canker or the causal fungi of this disease.Part of this report was presented at the 50th annual meeting of the Japan Wood Research Society, Kyoto, April 2000