• The Korean Journal of Ecology
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• v.13 no.4
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• pp.251-266
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• 1990

Extrafloral nectaries have been shown in many studies to promote mutualistic interactions between plants and insects(usually ants) that visit the glands. The insects gain sugars, water and amino acids secreted by the extrafloral nectaries and benefit the plants by reducing the damage caused by plant's inseet herbivores. Little is known about the occurrence of extrafloral nectaries in plants growing in Asia. To learn about the occurrence of extrafloral nectary bearing plants in Korea, living plants and herbarium material were examined for the glands. In addition, the cover of plants with extrafloral nectaries and the proportion of woody plants with extrafloral nectaries were measured in three forest communities on Kangwha Island. 131 species of plants belonging to 53 genera and 30 families were found to have extrafloral nectaries. These 131 species comprise about 4.0% of Korea's flora, a highet percentage of extrafloral nectary bearing plants than occurs in the studied areas of North America. Extrafloral nectary bearing plants occupied 7, 23 and 55% of the covers and comprised 15, 21 and 15% of the woody plants in the three different forests, a significant level of occurrence. Many important Korean crop plants were found to have extrafloral nectaries including : sesame (Sesamum indicum L.), squash (Cucurbita moschata Duchesne), sweet potato (Ipomoea batatas Lam), persimmon (Diospyros kaki Thunb.) cotton (Gossypium indicum Lam.), mung bean (Phaseolus radiatus L.), red bean (Phaseolus angularis W.F.), peach (Prunus persica (L) Batsch.), plum (Prunus salicina Lindl.). Many of these cultivated and wild plants may receive protection by ants and other beneficial insects that visit their extrafloral nectaries.

• Journal of Plant Biology
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• v.32 no.2
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• pp.101-107
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• 1989

Luffa acutanqula var. amara exhibits floral and extrafloral nectaries. The floral nectaries are restricted to the torus of the male flowers, while the extrafloral nectaries are observed on foliage leaves, probract, outer surface of calyx and pedicels. The floral nectaries develop from a group of epidermal and sub-epidermal initials which differentiate into secretory and subsecretory zones respectively during further divisions. The extrafloral nectary initiates from a single papillate nectary initial which gives rise to mature nectary comprising stalk layer, secretory and subsecretory tissues. Both the floral and extrafloral nectaries are vascularized. Interactions between insect-visitors and the plant with special reference to their functions are also discussed.

• Journal of Plant Biology
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• v.35 no.2
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• pp.143-153
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• 1992

Nectar secretion from extrafloral nectary cells of Prunus yedoensis was examined by light and electron microscopy. Nectaries were composed of two or three layers of secretory cells and one layer of subsectretory cells. Vascular bundles in the petioles were connected to those of the subsectretory cell layer. Secretory cells had a number of mitochondria with poorly developed cristae. Plastids had little thylakoids and small vesicles, about 0.2 to 0.3 mm in diameter; however, no plastids had starch grains. Calcium oxalate crystals and plasmodesmata were frequently observed in the subsectretory and secretory cells, respectively. And nectar substances were observed in phloem of petiole, subsectretory, and secretory cells of the secretory gland. These results suggested that the nectar moved by symplastic transport through the plasmodesmata. On the other hand, the nectar droplets were observed in the secretory cell walls. in the cuticular layer just beyond of the former, and on the outer surface of the cuticular layer: such observations indicated that a apoplastic movement was involved in the final step of the nectar secretion. Cellular components related to the nectar transport, such as plasma membrane, cell wall and cuticle were not destroyed but intact: it was interpreted as a eccrine secretion.retion.

• Korean Journal of Plant Taxonomy
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• v.49 no.2
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• pp.107-117
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• 2019

Viburnum in Korea includes ten species. The phylogenetic relationships and morphology of the genus Viburnum in general have been studied substantially for the past three decades. A clear understanding of the systematic relationships and an assessment of the level of morphological variation of these plants distributed in Korea are lacking. This study investigated the morphology of these species using herbarium specimens and fresh materials obtained during fieldwork to examine the morphological variation level for a better understanding of each species in the genus. A comparative analysis showed that the species of Viburnum in Korea are easily distinguishable based on various characters of the bud, leaf, extrafloral nectary, inflorescence, corolla, fruit, and stone.

• Korean Journal of Environment and Ecology
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• v.26 no.1
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• pp.39-45
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• 2012

To explore on the defense strategies against hervivory of 67 broadleaved tree species, morphological characteristics of the leaf, leaf domatia structure and the number, herbivores insects and mites on the leaves, collected from the trees growing in Taean-gun, Chuncheongnam-do were investigated. 46 broadleaved tree species(68.7%) had the domatia structures, and 21 species including Quercus salicina and Magnolia grandiflora did not. 31 species including Juglans mandshurica and Carpinus laxiflora reveals tuft type, 12 species including Quercus dentata and Corylus heterophylla reveals pocket+tuft type, and 2 species, Sorbus alnifolia and Prunus yedoensis does pocket type, and Viburnum odoratissimum var. awabuki does pouch type. Domatia number per leaf proves the highest figures, 23.4/leaf for Quercus dentata. Plant defense strategies using leaf lower-surface trichomes of Magnolia grandiflora reveals dense villous, those of Populus alba and Vitis vinifera reveals dense pilose, that of Elaeagnus umbellata does dense scaly hairs, that of Pueraria lobata does dense strigose. Plant defense strategies using extrafloral nectaries were adapted 23 tree species(34.3%). Observed examples are Prunus tomentosa, Ficus carica, Viburnum dilatatum and Carpinus laxiflora. Predatory mites were observed on the leaves of 40 tree species(59.7%), and mean values of predatory mites was highest values 23.4/leaf in Quercus dentata. Minute arthropods destroying the leaf of broadleaved trees. are such as Periphyllus californiensis, P. viridis, Diaspididae sp., gall mites, thrips, and total numbers observed were odered gall mites, Diaspididae sp., aphids and thrips. Natural enemies of these hervivores arthropods are such as predatory mites, Chilocorus rubidus, Coccinella septempunctata and the nymph, Aphidius ervi. These results indicate that defense strategies including protective mutualisms may be frequent in the temperate broadleave trees.

• Korean Journal of Environment and Ecology
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• v.26 no.3
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• pp.362-366
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• 2012

To explore on the defense strategies against hervivory of five Viburnum species, morphological characteristics of the leaf, leaf domatia structure and the number, herbivores insects and mites on the leaves, collected from the trees growing in Wonju-si, Pyeungchang-gun, Taebaek-si, Taean-gun, Bonghwa-gun, Sancheung-gun and Jinju-si were investigated from May 2009 to October 2011. Domatia of V. carlesii reveals pocket type, these of V. burejaeticum, V. dilatatum and V. wrightii reveal tuft type, and that of V. odoratissimum var. awabuki reveals pouch type. Domatia number per leaf proves the highest figures, 24.0/leaf for V. burejaeticum, and the lowest, 4.9/leaf for V. carlesii. Leaf surface trichomes of four Viburnum species except for V. odoratissimum var. awabuki are mainly stellate and hispid on the leaf-blade and veins, and dense stellate trichomes on the upper leaf surface of V. carlesii, V. burejaeticum, and V. dilatatum are observed till late growing season. Extrafloral nectaries(EFN) on the terminal veins of five Viburnum species are observed. Pellucid dots on the lower leaf surface of V. dilatatum and V. wrightii might be a good defense strategies against herbivores. We observe many predatory mites eating nectar on large pellucid dots of V. dilatatum. Predatory mites number per leaf proved highly significant differences among tree species, and mean of mites number was highest values 8.1/leaf for V. burejaeticum, and the lowest 2.6/leaf for V. odoratissimum var. awabuki. These results indicate that temperate broadleave trees develop various defense strategies against herbivores for survival. The more studies on the defense strategies against herbivores of tree species might be needed for sustainable forest ecosystem.

• Korean Journal of Environment and Ecology
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• v.23 no.5
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• pp.411-417
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• 2009

This research is intended to discover physiological and biochemical defense mechanisms against herbivores of 8 species of the genus Acerby examining the morphological characteristics of the leaf, the structure and number of leaf domatia, herbivores insects and mites feeding on leaves, which were collected from the trees growing in Mt. Chiak, Mt. Cheongtae, Mt. Jungwang, Mt. Bangtae, Mt. Taebaek and Wonju City. This research was conducted from May through July, 2009, and the results are as follows. The domatia of A. pseudosieboldianum, A. pictum subsp. mono and A. mandshuricum belongs to tuft type; that of A. palmatum, A. triflorum and A. tschonoskii pocket+tuft type; and that of A. tegmentosum pocket type. The number of domatia per leaf turned out to be the highest in the case of A. tegmentosum(20.2), and the lowest in the case of A. ginnala (4.2). Leaf surface trichomes of A. palmatum, A. pseudosiebotdianum, A. ginnala and A. mandshuricum are covered with villi; those of A. pictum subsp. mono and A. triflorum with soft, pilose type of hair, and those of A. tschonoskii with stiff, strigose hair. The trichome density of lower leaf surface is found to be higher than that of the upper leaf surface. Only in the case of A. palmatum, A. pseudosieboldianum, A. tegmentosum and A. tschonoskii, a small amount of nectar is found to be secreted from the distal vein parts of the leaf margin. The number of mites on each leaf are found to be significantly different among tree species, and average mites number per leaf was the highest in the case of A. tschonoskii (9.2/leaf), and A. mandshuricum, A. pseudosieboldianum, and A. triflorum follow it in decreasing order. Minute insects attacking the leaf of Acer spp. include Periphyllus californiensis, P. viridis, Psylla spp, and gall mites, and the number of these insects are found in Periphyllus californiensis, Psylla spp, P. viridis, and Cicadellidae sp. in decreasing order. The natural enemies of these herbivores insects are predatory mites, such as Chilocorus rubidus, Coccinella septempunctata and the nymph, Aphidius ervi, Poecilocoris lewisi and its larva, and Poecilocoris lewisi. Lasius japonicus and Formica japonica are symbiotic with aphids, and supports herbivores. Finally, our research confirmed that predatory mites attack Periphyllus californiensis and suck the body fluid of their victim. This proves that mites form a symbiotic relationship with plants through the mediation of leaf domatia. This also indicates that a protective mutualism may be more conspicuous in temperate broad-leaved trees.