Showing papers on "Bark published in 1986"

Dosage response to ethanol mediates host selection by “secondary” bark beetles

Abstract: common one responded mainly to Z 9 14:OAc, a second type to Z7+ 14: OAc with a weak response also to Z 9 14:OAc, and a third type responded exclusively to Z11-14: OAc (Fig. 2). The medial shorter sensilla towards the antennal axis have two cells: Cell A with a high spike amplitude and cell B with a low spike amplitude. The A cell responds to totally different pheromone components than the cells in the marginal long sensilla: the majority (82%) responds to Z5-14: OAc, whereas a lower number (18%) is activated exclusively by Z7-12:OAc (Fig. 2). The function of the B cell is still unknown. It did not respond to any of the compounds tested. These results were corroborated by measuring the response of ten short sensilla to the same compounds with the penetration technique [81. The receptor types found by us are thus in agreement with what Priesner reported [6]. The proportion of sensillacontaining cells sensitive to compounds other than Z5and Z9-14:OAc is striking. Trapping experiments by Priesner [6] showed that these other compounds have an inhibitory effect on the attraction of male A. exctarnationis. Our own unpublished gas chromatographic analyses on capillary columns did not reveal traces of any of them in female extracts (<0 .5% of Z5 14:OAc). They are, thus, most probably pheromone compounds in some other competing species. More interestingly, however, we found a clearcut correlation between the morphology of individual sensilla, their spatial localization, and their sensitivity to different compounds. The receptors for the pheromone component z g 1 4 : O A c are exclusively arranged along the lateral margins of the antennal segments, and are each innervated by one neuron. The Z 5-14:OAc receptors are all placed medially in sensilla containing also a second cell. Such a spatial arrangement of receptors sensitive to different pheromone components has not been reported before. It is interesting to note that Z 9 14: OAc is perceived by a specific cell in the long distal sensilla placed on the edge of the male A. exclarnationis antennal segments. There is in the pheromone blend an optimal proportion of this component to Z5-14: OAc of less than 10% for male attraction. The proportion of molecules perceived by the sensilla from the air is by aerodynamic laws much higher for distal sensilla than for central ones [9]. This means that the localization of the Z 9 t 4 : OAc receptors on the male A. exclamationis antenna could be adaptive for sensitive detection of the m i n o r o n e of the two pheromone components. Received November 25, 1985 and January 10, 1986

Seasonal Fluctuations of Lectins in Barks of Elderberry (Sambucus nigra) and Black Locust (Robinia pseudoacacia)

Abstract: Elderberry (Sambucus nigra) and black locust (Robinia pseudoacacia) agglutinins, which are abundantly present in the bark of both species, display seasonal fluctuations with regard to their content in this tissue. These seasonal changes result apparently from a circa-annual rhythm of lectin accumulation and depletion during autumn and spring, respectively. Because the bark of trees can be considered as a type of vegetative storage tissue, the results suggest that bark lectins behave as typical storage proteins.

Sambucus nigra agglutinin is located in protein bodies in the phloem parenchyma of the bark.

Abstract: The bark of some young woody stems contains storage proteins which are subject to an annual rhythm: they accumulate in the autumn and are mobilized in the spring. We show here that the bark phoem-parenchyma cells of Sambucus nigra L. contain numerous protein bodies, and that the bark lectin (S. nigra agglutinin) which undergoes an annual rhythm is localized in these protein bodies. The protein bodies in the cotyledons of legume seeds also contain lectin, indicating that lectins may be storage compounds themselves or may have a function in storage and-or mobilization processes.

Wound responses in girdled stems of lianas

Abstract: Nineteen species of lianas, some with typical secondary growth and some with anomalous secondary growth, were girdled by removing either one-half or the entire bark. Although regeneration occurred in stems with typical secondary growth, it was not as great as in stems with anomalous secondary growth. In stems with lenses of apotracheal parenchyma, most regeneration occurred from the parenchyma and was so great that the secondary xylem was fragmented into small individual pieces. In half-girdled stems of lianas with supernumerary cambia, proliferation occurred from the xylem and phloem rays, all cambia, and phloem nearest the exposed surfaces at the lateral edges of the girdle. In full-girdled stems, regeneration occurred from the innermost cambia as well as from internal phloem. All species with lobed xylem and disjunct cambium had prolific regeneration that always occurred from the furrows of phloem between the xylem lobes. In some full-girdled stems, callus that formed on the periphery of the stem devel...

Comparison of interactions between Ceratocystis ulmi and elm bark saprobes in vitro and in vivo

Abstract: Of nineteen species of fungi isolated from elm bark, sixteen significantly reduced the growth of Ceratocystis ulmi during competitive interactions in culture. When directly confronted with the pathogen in elm bark only three species were capable of replacing already established C. ulmi colonies, while four others showed some potential to exclude C. ulmi during the initial stages of bark colonization by virtue of their effectiveness as primary colonizers. On the basis of these results the potential for natural biological control of C. ulmi by competitive saprobes in elm bark is discussed. The common practice of basing conclusions about interactions between fungi in nature, based solely on in vitro experiments, is also questioned.

Tannins from four common Acacia species of Texas and northeastern Mexico.

Abstract: The amount of tannins present inAcacia berlandierii, A farnesiana, A greggii andA rigidula, 4 common species of the southwestern United States and northern Mexico, was determined Bark samples of the 4 species were extracted with water, 80% methanol, and 70% acetone Of these, 70% acetone proved to be the most efficient solvent Tannins were determined by Folin-Denis analysis for total phenolic materials, followed by precipitation with casein or hide powder The hidepowder method was modified to facilitate handling of smaller samples Results of tannin determination by casein and hide-powder precipitation methods gave comparable results The amount of tannins present in leaves, bark, wood, and immature fruits of samples of these species was then determined by the same analytical methods In most instances, bark and immature fruits had the highest percentage of tannins (5–15%) and wood was much lower (less than 1%) Leaves had intermediate values

Autumnal changes in total nitrogen, salt-extractable proteins and amino acids in leaves and adjacent bark of black alder, eastern cottonwood and white basswood

Abstract: Autumnal changes in total nitrogen, salt-extractable protein and amino acid concentrations in leaves and adjacent bark of black alder [Ainus glutinosa (L.) Gaertn.], eastern cottonwood (Populus deltoides Bartr. ex Marsh.) and white basswood (Tilia heterophylla Vent.) were determined for trees growing on minespoils and a prairiederived loamy soil in central Illinois. The composition of free amino acids in foliage was also determined at peak concentration for each tree species during late senescence. Total nitrogen concentration in the leaves decreased slowly throughout most of the fall for all species. In the final stages of senescence, total leaf nitrogen concentrations were about halved in eastern cottonwood and white basswood but continued to decrease slowly in black alder. The concentration of salt-extractable proteins in leaves of all species peaked early in the fall and then declined prior to leaf abscission. This decline coincided with an increase in the concentration of free amino acids in the leaves. The increase stabilized in both eastern poplar and white basswood but continued in black alder. Glutamine in black alder and eastern cottonwood, and asparagine in white basswood were the most abundant free amino acids at the time of peak concentration of total free amino acids in senescent leaves. Bark of trees of all species had higher nitrogen concentrations and higher proportions of salt-extractable proteins to estimated total proteins after leaf senescence than during the preceding summer. Results indicate that autumnal fluxes in leaf and bark nitrogen fractions of alder can differ substantially from fluxes in other broadleaved winter-deciduous trees in a way which suggests that alder does not effectively conserve leaf nitrogen through retranslocation to bark tissue.

Quantification of different yeasts associated with the bark beetle,Ips typographus, during its attack on a spruce tree.

Abstract: There were different amounts and types of yeasts associated with individuals ofIps typographus spruce bark beetles during different phases of their attack on a healthy spruce tree. The yeasts were isolated on Sabouraud agar medium in order to identify them and estimate their numbers.Hansenula holstii andCandida diddensii type yeasts were most frequently isolated. The increase in number of these two yeast types probably accounted for most of the total yeast increase found during the later attack phases of the bark beetles. Lesser amounts ofHansenula capsulata, Pichia pinus, Candida nitratophila, and twoCryptococcus type yeasts were also found.

Defensive mechanisms of loblolly and shortleaf pine against attack by southern pine beetle,Dendroctonus frontalis Zimmermann, and its fungal associate,Ceratocystis minor (Hedgecock) Hunt.

Abstract: Loblolly and shortleaf pine growing on a single site in the North Carolina piedmont were examined to determine similarities and differences in their defensive mechanisms against the southern pine beetle,Dendroctonus frontalis Zimmermann, and its fungal associate,Ceratocystis minor (Hedgecock) Hunt. Both species responded to wounding and fungal inoculation by forming a hypersensitive lesion around the wound site. There were significantly less soluble sugars and more monoterpenes in the lesion tissue than in unwounded inner bark. The two species were similar in resin flow rate and inner bark soluble sugar content, but the loblolly pines had thicker bark, longer hypersensitive lesions, and a higher concentration of inner bark monoterpenes. Inner bark monoterpene composition was also significantly different between the two pine species. It is hypothesized that two different defensive strategies against southern pine beetle attack may be utilized.

Fine structure of the suberized cell walls in the boundary zone and necrophylactic periderm in wounded peach bark

Abstract: Bark on the scaffold limbs of 6-year-old peach (Prunus persica (L.) Batsch cv. Redhaven) trees was mechanically wounded and tissue samples for ultrastructural study were taken after 6, 8, 12, and 1...

Adult populations of the sugi bark borer, Semanotus japonicus Lacordaire (Coleoptera: Cerambycidae), in japanese cedar stands: population parameters, dispersal, and spatial distribution

Abstract: Adult populations of the sugi bark borer,Semanotus japonicusLacordaire, which attacks the trunks of Japanese cedar and cypress, were studied in two cedar stands in 1981 and 1984, using a band-trapping method developed by the author.

Distribution and yield of biomass from young Pinus sylvestris and Picea abies stands on drained and fertilized peatland

Abstract: Above‐ground biomass has been measured on fertilized and control plots up to stand age 31 years. Each biomass fraction was estimated by two statistically coupled linear models with squared diameter at breast height as independent variable. All fractions except reproductive structures of pine and dead branches of spruce were estimated at high precision levels, R. between 0.93 and 0.99. The above‐ground biomass fractions per hectare could be precisely described by stem volume with bark. Application of the models for prognostic purposes is discussed. Annual above‐ground net biomass production in pine increased from 2.05 to 4.34 MT d.m./ha‐yr on control plots over 11 years, while plots given complete fertilizer mixture ranged from 6.75 to 9.09. Spruce stands with a nearly optimum water relationship and fertilizer programmes yielded from 9.50 to 11.86 MT d.m./ha‐yr. The combination of energy and timber production in highly productive peatland stands is discussed.

Wound age and infection of peach bark by Cytospora leucostoma

Abstract: Peach bark wounds of varying ages were inoculated with mycelium of Cytospora leucostoma (Pers.) Fr., and colonization frequency and extent were determined. Noninoculated wounds of similar ages and in close proximity to inoculated wounds were also sampled and examined histologically for morphological and histochemical changes associated with nonspecific plant defense reactions, including lignification and formation of lignosuberized tissue and new periderm. Results demonstrated that lignified and lignosuberized tissues significantly decreased the rate of fungal colonization, whereas new periderm with at least three cells thickness of new phellem completely inhibited fungal colonization. The critical period regarding effective periderm formation was between 10 and 14 days postwounding.

Susceptibility to vole attacks due to bark phenols and terpenes inPinus contorta provenances introduced into Sweden.

Abstract: Seedlings of North AmericanPinus contorta introduced to Sweden and Finland are severely gnawed by voles, e.g.,Microtus agrestis. The level of damage varies between provenances. Chemical analyses of various phenolic compounds, monoterpenes, and resin acids of different provenances and of damaged and undamaged stems showed that some phenolic substances in the bark increased after damage without deterring the animals, that monoterpene differences between provenances were not related to vole damage, and that certain resin acids occurred in larger amounts in lightly than in severely damaged provenances. Levopimaric and neoabietic acid, and possibly abietic acid, may be important for a partial resistance to vole browsing.

A Study of the Constituents of the Bark of Chamaecyparis Formosensis Matsum

Abstract: Sixteen compounds were isolated from the bark of Chamaecyparis formosensis Matsum. These compounds include four categories: (a) long-chain alcohols, acids and esters, (b) sterols and their glucosides, (c) o-methoxyphenol and related compounds, (d) diterpenes of abietane, pimarane, secoabietane and totarane.

Anthraquinones in Cinchona ledgeriana Bark Infected with Phytophthora cinnamomi

Abstract: The contents of secondary metabolites (alkaloids and anthraquinones) in CINCHONA LEDGERIANA bark infected with PHYTOPHTHORA CINNAMOMI and in non-infected bark were determined. It was found that the alkaloid content of the infected bark was lower. Whereas no anthraquinones could be detected in the healthy bark, these compounds were present in the infected bark. So, anthraquinones in CINCHONA act as phytoalexins.

Fractionation of hot water extract from Picea abies Karst. bark

Abstract: The hot water extract of Picea abies bark (Stiasny number 52.2), used as wood adhesive, was studied for heterogeneity by chromatography with an Amberlite XAD-8 gel. The Stiasny numbers of the tannin fractions were found to be repeatedly over 80 and those of the water fractions less than 15. However, the tannin/carbohydrate resolution was not as good for the ethanol fraction obtained by a Soxhlet extraction of spruce bark hot water extract. This is probably due to the glycosidic nature of this fraction.