• Title/Summary/Keyword: plant associations

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Structural Characteristics of Cell Walls of Forage Grasses - Their Nutritional Evaluation for Ruminants - - Review -

  • Iiyama, Kenji;Tuyet Lam, Thi Bach
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.6
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    • pp.862-879
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    • 2001
  • The walls of all higher plants are organized as a cellulosic, fibrillar phase embedded in a matrix phase composed of non-cellulosic polysaccharides, some proteins and, in most secondary walls, lignin. At the effective utilization of plant biomass, qualitative and quantitative analyses of plant cell walls are essential. Structural features of individual components are being clarified using newly developed equipments and techniques. However, "empirical" procedures to elucidate plant cell walls, which are not due to scientific definition of components, are still applied in some fields. These procedures may give misunderstanding for the effective utilization of plant biomass. In addition, interesting the investigation of wall organization is moving towards not only qualitatively characterisation, but also quantitation of the associations between wall components. These involve polysaccharide-polysaccharide and polysaccharide-lignin cross-links. Investigation of the associations is being done in order to understand the chemical structure, organization and biosynthesis of the cell wall and physiology of the plants. Procedures for qualitative and quantitative analyses based on the definition of cell wall components are reviewed focussing in nutritional elucidation of forage grasses by ruminant microorganisms.

Effects of Forest Management Practices and Environment on Occurrence of Armillaria Species

  • Kim, Mee-Sook;Klopfenstein, Ned B.;Mcdonald, Geral I.
    • Journal of Korean Society of Forest Science
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    • v.99 no.2
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    • pp.251-257
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    • 2010
  • Influences of environment (indicated by plant associations) and forest management practices on the distribution of Armillaria spp. and genets (vegetative clones) were investigated. A total of 142 isolates of Armillaria was collected from various host trees on pristine and managed sites (thinned and/or fertilized) growing in relatively wet and dry environments in eastern Washington, U.S.A. The incidence of Armillaria spp. was significantly higher in the relatively wetter sites than the relatively drier sites, as indicated by plant associations. However, no differences in Armillaria occurrence were found among different forest management practices (control vs. thinned vs. thinned and fertilized) within both wetter and drier sites. Incidence of Armillaria was significantly different among conifer and shrub species. The highest proportion with Armillaria was found on grand fir (Abies grandis). Based on pairing tests and rDNA sequencing, the 142 isolates were comprised in a total of 20 genets representing three Armillaria species. More diverse Armillaria spp. were found in both relatively wetter and relatively drier sites within the undisturbed control plots, compared to plots disturbed by forest management practices. The results from this study provide baseline information toward understanding how environment and forest management practices influence incidence and diversity of Armillaria species and genets.

Roles of flower scent in bee-flower mediations: a review

  • Bisrat, Daniel;Jung, Chuleui
    • Journal of Ecology and Environment
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    • v.46 no.1
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    • pp.18-30
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    • 2022
  • Background: Bees and flowering plants associations were initially began during the early Cretaceous, 120 million years ago. This coexistence has led to a mutual relationship where the plant serves as food and in return, the bee help them their reproduction. Animals pollinate about 75% of food crops worldwide, with bees as the world's primary pollinator. In general, bees rely on flower scents to locate blooming flowers as visual clue is limited and also their host plants from a distance. In this review, an attempt is made to collect some relevant 107 published papers from three scientific databases, Google Scholar, Scopus, and Web of Science database, covering the period from 1959 to 2021. Results: Flowering plants are well documented to actively emit volatile organic compounds (VOCs). However, only a few of them are important for eliciting behavioral responses in bees. In this review, fifty-three volatile organic compounds belonging to different class of compounds, mainly terpenoids, benzenoids, and volatile fatty acid derivatives, is compiled here from floral scents that are responsible for eliciting behavioral responses in bees. Bees generally use honest floral signals to locate their host plants with nectar and pollen-rich flowers. Thus, honest signaling mechanism plays a key role in maintaining mutualistic plant-pollinator associations. Conclusions: Considering the fact that floral scents are the primary attractants, understanding and identification of VOCs from floral scent in plant-pollinator networks are crucial to improve crop pollination. Interestingly, current advances in both VOCs scent gene identification and their biosynthetic pathways make it possible to manipulate particular VOCs in plant, and this eventually may lead to increase in crop productivity.

Phytosociological Classification of Plant Communities in Mt. Naejang, Southwestern Korea (내장산 식물군집의 식물사회학적 분류)

  • 김정언
    • Journal of Plant Biology
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    • v.31 no.1
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    • pp.1-31
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    • 1988
  • The forest vegetation of Mt. Naejang, southwestern Korea were classified into ten associations in four alliances of one order by Z-M school method as follows: Quercetalia serrato-mongolicae ord. nov. Rhododendro-Pinion densiflorae all. nov. Rhododendro mucronulati-Pinetum densiflorae Kim et Yim 1986 Acero-Quercion mongolicae all. nov. Rhododendro-Quercetum mongolicae assoc. nov. Carpinion laxiflorae Kim et Yim 1986 Quercetum variabilis Kim et Yim 1986 Carpinetum laxiflorae Kim et Yim 1986 Carpinetum tschonoskii Kim et Yim 1986 Daphniphyllum macropodum community Quercus aliena-Carpinus tschonoskii community Corno-Zelkovion serratae all. nov. Corno-Linderetum erythrocarpae assoc. nov. Torreyo-Zelkovetum serratae assoc. nov. Acero-Zelkovetum serratae assoc. nov. On the other hadn four groups and six subgroups were divided by the species association, and their groups and subgroups showed the coincidence with the alliances and associations, phytosociological units.

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Coastal Dune Vegetation of South Korea

  • Lee, Jeom-Sook;Ihm, Byung-Sun;Cho, Du-Sung;Kim, Jong-Wook
    • Journal of Ecology and Environment
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    • v.30 no.2
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    • pp.135-142
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    • 2007
  • We used the Braun-Blanquet method to study coastal dune vegetation of South Korea. Coastal vegetation was monitored in thirty sites from April 2004 to September 2005. Seventeen plant communities were classified into five groups as follows: A. Two associations of herbaceous sand dune plants in Salsoletea komarovii Ohba, Miyawaki et Tx. 1973 (Calystegia soldanella community, Lathyrus japonicus-Calystegia soldanella community), B. Twelve associations of herbaceous perennial sand dune plants in Glehnietea littoralis Ohba, Miyawaki et Tx. 1973 (Carex pumila community, Elymus mollis community, Vitex rotundifolia-Elymus mollis community, Ixeris repens community, Elymus mollis-Ixeris repens community, Lathyrus japonicus community, Messershmidia sibirica community, Glehnia littoralis community, Carex kobomugi community, Calystegia solda-nella-Carex kobomugi community, Ishaemum anthephoroides community, Zoysia macrostachya community), C. One association of shrubby perennial sand dune plant in Viticetea rotundifoliae Ohba, Miyawaki et Tx. 1973 (Vitex rotundifolia community), D. One association of shrubby perennial sand dune plant in Rosetea multiflorae Ohba, Miyawaki et Tx. 1973 (Rosa rugosa community), E. The naturalized community (Diodia teres community).

Phytosociological Classification of Plant Communities on Mt. Halla National park, Korea (漢拏山國立公圓 植物群集의 植物社會學的 分類)

  • Yim Yang-Jai;Jeong-Un Kim;Nam-Ju Lee;Yong-Beom Kim;Kwang-Soo Paek
    • The Korean Journal of Ecology
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    • v.13 no.2
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    • pp.101-130
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    • 1990
  • The forest vegetation of Mt. Halla national park area. Cheju island, Korea, was classified into six associations in three alliances and two associations in unidentified alliances by Z-M school method as follows: Unidentified alliance Saso-Abietetum Koreanae assoc. nov. Acero-Quercion mongoliae Kim et Yim 1988 Hepatico-Quercetum mongolicae assoc. nov. Saso-Carpinioin laxiflorae all. nov. Saso-Carpinetum laxiflorae assoc. nov. Daphniphyllo-Carpinetum tschonoskii assoc. nov. Asaro-Quercetum serratae assoc. nov. Rhododendro-Pinion densiflorae Kim et Yim 1988 Saso-Pinetum densiflorae assoc. nov. pinus thunbergii community Unidentified alliance Ardiso-Torretum nuciferae assoc. nov. Among them one now alliance and seven new associations were found and marked with "nov."

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The Presence and Importance of VAM Spores in the Soil of Ginseng Gardens

  • Weber, Hans-Christian
    • Proceedings of the Ginseng society Conference
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    • 1998.06a
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    • pp.90-95
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    • 1998
  • Symbiotic associations between land plants and fungi have been known for more than one hundred years. Vesiculararbuscular mycorrhizas (VAM) are the most common symbiosis in flowering plants and can be recognized in almost all plant families. These fungal associations play a very important role in the growth and survival of plant species. However, with respect to the importance and intensity of the VAM, there is great variation among host species. Our knowledge of the VAM fungus-plant association in Araliaceae is very limited. After the first reports of the occurence of VAM in lateral roots of Panax species, mycorrhizal structures are now described as special structures representing the so-called Paris type. In this type, the development of new spores and vesicles is extremely low. This and the type of colonization of the fungus in Panax roots indicates on, one hand, the high intensity of the VAM and, on the other hand, a remarkable dependency for VAM in members of the Panax species. Therefore, it can be easily understood that cultivated Panax plants exhibit a significant uptake of nutrients and this leads to an extremely depleted soil at harvest. Further, the soil is nearly free of the spores of VAM fungi as they germinate each year on the newly developing Panax roots.

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An Analysis of Ecological Factors Limiting the Distribution of a Group of Stipa pulchra Associations

  • Robinson, Richard Hayes
    • Journal of Plant Biology
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    • v.14 no.3
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    • pp.1-20
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    • 1971
  • Ecological factors limiting Stipa pulchra have been determined in experimental gardens and at several sites in the hills south and east of Monterey, California. The Stipa pulchrafacies of Valley Grassland communities were found to be dominated by that species, though a total of 36 grasses and forbs were collected and identified. Basal area was not large, but aerial cover by Stipa alone averaged over 50 per cent. Across an ecotone between a Stipa association and the California Annual Type a sudden and dramatic change was recorded. Soil measurements there, and in other nearby areas, showed a much higher clay content with more available water and elemental phosphorus at the Stipa sites. Germination of Stipa seeds was high under all laboratory and field conditions, though growth of seeldings was highly variable. Seedlings grown in Stipa woil with an abundance of water were vigorous and reached anthesis the first year. In other soils they grew less, and when grown in competition with Avena fatua they scarcely grew at all. These findings indicate that when established on desirable soils, Stipa competes well and apparently precludes the dominance of Avena fatua and other large annual grasses. On the other hand, because of a lack of vigor in its seedlings, Stipa cannot reinvade the rich more friable soils on which it was once found, and on which it was shown to grow satisfactorily. This supports the contention that Sipa pulchra was the dominant grass through much of the Valley Grassland and Foothill Woodland, but also indicates that well-drained soils and those poor in mineral nutrients probalby never supported such associations.

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Genetic variability, associations, and path analysis of chemical and morphological traits in Indian ginseng [Withania somnifera (L.) Dunal] for selection of higher yielding genotypes

  • Srivastava, Abhilasha;Gupta, Anil K.;Shanker, Karuna;Gupta, Madan M.;Mishra, Ritu;Lal, Raj K.
    • Journal of Ginseng Research
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    • v.42 no.2
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    • pp.158-164
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    • 2018
  • Background: The study was carried out to assess the genetic variability present in ashwagandha and to examine the nature of associations of various traits to the root yield of the plant. Methods: Fifty-three diverse genetic stocks of ashwagandha (Withania somnifera) were evaluated for 14 quantitative characteristics. Analysis of variance, correlation, and path coefficient analysis were performed using the mean data of 2 years. Results: Analysis of variance revealed that the genotypes differed significantly for all characteristics studied. High heritability in conjunction with high genetic advance was observed for fresh root weight, 12 deoxywithastramonolide in roots, and plant height, which indicated that selection could be effective for these traits. Dry root weight has a tight linkage with plant height and fresh root weight. Further, in path coefficient analysis, fresh root weight, total alkaloid (%) in leaves, and 12 deoxywithastramonolide (%) in roots had the highest positive direct effect on dry root weight. Conclusion: Therefore, these characteristics can be exploited to improve dry root weight in ashwagandha genotypes and there is also scope for the selection of promising and specific chemotypes (based on the alkaloid content) from the present germplasm.