• Korean journal of applied entomology
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• v.32 no.3
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• pp.338-347
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• 1993

The study was to investigate the bionomics, host plants, and oviposition preference of Hishimonus sellatus Uhler. It has 5 generations under natural conditions and the peak of the 3rd generation was observed about mid and late August. Its average developmental durations were 80 days in spring, 69 days in summer, and 77.8 days in autumn. The lengths of each stage were 0.8mm in eggs, 0.9mm in 1st instar, 1.4mm in 2nd instar, 2.1mm in 3rd instar, 2.5mm in 4th instar, 3.2mm in 5th instar, 4.1mm in female, and 3.8mm in male. Hishimonus sellatus overwintered as egg in Morus alba, Humulus japonicus, and Zizyphus jujuba begining mid October, and attacked the shoot of M. alba and H. japonicus about mid and late May, migrated to the Zizyphus jujuba from late June to early July. Female oviposites 32~62 eggs into epidermis of shoot, vagina and vein during their life. The preferred host plants of H. sellatus were Humulus japonicus, Morus alba, Zizyphus jujuba, and ligustrum obtusifolium. Highly preferable oviposition site was H. japonicus, M. albal, Z. jujuba, and L. obtusifolium, etc. On audlt longevity, the host plants as H. japonicus, M. alba, and Z. jujuba were 43$\pm$2 days and A. brevipedenculata, C. mimosoides, L. obtusifolium, V. rosa, A. sinicus and, A. graveolens were more than 25 days, and other host plants were less than 20 days.

• Journal of Korean Society of Forest Science
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• v.48 no.1
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• pp.29-39
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• 1980

This study was initiated to find out the possible insect vector and other means of transmission of jujube witches'-broom disease. 1. Eight species of leafhoppers were found to feed on both healthy and diseased jujube trees. Among these, rhombic marked leafhoppers (Hishimonus sellatus Uhler) were most abundant throughout the growing season of jujube trees in all localities surveyed. H. sellatus was far more abundant on diseased trees than healthy ones. 2. Jujube witches'-broom mycoplasma(JWM) was transmitted to jujube seedlings by Hishimonus sellatus. Jujube seedlings inoculated with H. sellatus which had been fed for 14-21 days on diseased jujube plants, developed smaller, chlorotic leaves 40-60 days after inoculation. Electron microscopy of midveins and petioles of the infected jujube seedlings revealed the presence of numerous mycoplasmalike organisms in phloem tissues. 3. Jujube witches'-broom mycoplasma was also transmitted to Vinca rosea plants by H. sellatus. Infected Vinca rosea plants developed vein clearing and marginal chlorosis of upper leaves 25-38 days after inoculation and followed by stunting and ultimate wilting and death of plant. Electron microscopy of petioles and midveins of infected Vinca rosea plant revealed the presence of numerous mycoplasmalike organisms in phloem tissues. 4. H. sellatus survived more than 30 days on jujube, Vinca rosea, carrot, celery, eggplant, hop, Calystegia japonica, Humulus japonicus, Astragalus sinicus, white clover, red clover, and radino clover. Many second generation nymphs of H. sellatus were also abserved on these plants but clovers. 5. Jujube seeds collected from witches'-broom diseased jujube trees yielded healthy seedlings.

• Korean Journal Plant Pathology
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• v.1 no.3
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• pp.184-189
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• 1985

Transmission of mulberry dwarf mycoplasma (MDM) from diseased mulberry to 5 herbaceous plants (periwinkle, white clover, Ladino clover, red clover, and Chinese milk vetch) through insect vector, Hishimonus sellatus, was confirmed by symptom expression and microscopic evidences. The earliest symptom appearance was noticed on periwinkle in which incubation period was 25-30 days, while it ranged 35-40 days in the other plant species. The common symptoms of MDM infected plants were characterized by poor plant growth with accompanying discolorations of leaves (chlorosis with vein clearing in periwinkle, reddish in red clover, brownish in white and Ladino clovers, and yellowish in Chinese milk vetch). Mycoplasmal infections were diagnosed light microscopically by Dienes' and toluidine blue staining of hand-cut and Epon-embedded sections, respectively. In Dienes' stain, all the plants infected with MDM showed specific staining reaction in phloems. In toluidine blue stain, mycoplasmal existence was noted by granular appearance in sieve tubes which were confirmed to be mycoplasma-like organisms under an electron microscope.

• The Plant Pathology Journal
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• v.28 no.3
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• pp.239-247
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• 2012

Phytoplasmas have been associated with more than 46 plant species in Korea. Several vegetables, ornamentals, fruit trees and other crop species are affected by phytoplasma diseases. Six 16Sr groups of phytoplasmas have been identified and these phytoplasmas are associated with 63 phytoplasma diseases. Aster yellows phytoplasmas are the most prevalent group and has been associated with more than 25 diseases in Korea. Jujube witches' broom, paulownia witches' broom and mulberry dwarf diseases cause economic losses to host trees throughout the country. So far, Korean phytoplasmas belong to six species of 'Candidatus Phytoplasma'; 'Ca. P. asteris', 'Ca. P. pruni$^*$', 'Ca. P. ziziphi', 'Ca. P. trifolii', 'Ca. P. solani$^*$' and 'Ca. P. castaneae'. The diseases are distributed throughout the country and most of them were observed in Gyeongbuk and Chonbuk provinces. At least four insect vectors; Cyrtopeltis tenuis, Hishimonus sellatus, Macrosteles striifrons and Ophiola flavopicta have been identified for phytoplasma transmission.

• The Plant Pathology Journal
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• v.18 no.2
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• pp.98-101
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• 2002

Using phytoplasma universal primer pair Pl and P7, a fragment of about 1.8 kb nucleotide sequences of 16S rRNA gene and 16S-23S rRNA intergenic spacer region, and a portion of 23S rRNA gene of jujube witches'broom (JWB) and mulberry dwarf(MD) phytoplasmas were determined. The nucleotide sequences of JWB and MD were 1,850 bp and 1,831 bp long, respectively. The JWB phytoplasma sequence was aligned with the homologous sequence of MD phytoplasma. Twenty-eight base insertions and nine base deletions were found in the JWB phytoplasma sequence compared with that of MD phytoplasma. The similarity of the aligned sequences of JWB and MD was 84.8%. The near-complete 16S rRNA gene DNA sequences of JWB and MD were 1,529 bp and 1,530 bp in length, respectively, and revealed 89.0% homology. The 16S-23S rRNA intergenic spacer region DNA sequences were 263 bp and 243 bp in lengths respectively, while homology was only 70% and the conserved tRNA-lle gene of JWB and MD was located into the intergenic space region between 16S-23S rRNA gene. The nucleotide sequences were 77 bp long in both JWB and MD, and showed 97.4% sequence homology. Based on the phylogenetic analysis of the two phytoplasmas, the JWB phytoplasma belongs to the Elm yellow phytoplasma group (16S rV), whereas, the MD phytoplasma belongs to the Aster yellow group (16S rI).

• Journal of Korean Society of Forest Science
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• v.78 no.2
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• pp.103-118
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• 1989

The occurrence of witches' broom in Ligustrum ovalifolium was first noticed in Korea by author in 1984. The present study was carried out with particular emphasis on the symptomatology, etiology, transmission of the disease and antibiotic treatments. The infected tissue was observed by the fluorescence and electron microscopy and its biochemical characteristics were compared with healthy one by electrophoresis. The results are summarized as follows : 1. symptoms of the infected trees were characterized by the dwarfing of the organs, yellowing and brooming of the foliage. 2. The observation by the trans electron microscopy on the witches' broom of L. ovalifolium revealed the occurrence of numerous mycoplasma-like organisms(MLOs) in the phloem tissue cells of the midribs of infected leaves. 3. The MLOs were surrounded by a single unit membrane, and they appeared to be multiplied by binary fission. 4. The presence of crystals unidentified in the phloem parenchyma cells was noticed by electron rnicroscopy, 5. The disease was able to be transmitted by budding, crown, and greenwood graftings to L. ovalifolium, L. obtusifolium, L, japonicum and also transmitted, even when the stocks and scions were not completely grafted. 6. Insect transmission on L. ovalifolium and L, obtzrsifolium was carried by Hishimonus sellatus. 7. The infected roots dipped in the 1,000 ppm of teracyclin solution was only temporarily effective in controlling the disease. 8. Infected plant with MLOs showed specific fluorescent reactions in phloems with DAPI stain. 9. The protein and peroxidase separated by electrophoresis showed strikingly distinctive difference between the healthy and diseased leaves.