• Plant Biotechnology Reports
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• v.3 no.1
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• pp.1-56
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• 2009

Orchid seeds are nearly microscopic in size. Because of that, many fanciful theories were proposed for the origin of orchids. Almost 400 years separate the time when orchid seeds were seen for the first time and the development of a practical asymbiotic method for their germination. The seeds were first observed and drawn during the sixteenth century. Seedlings were first described and illustrated in 1804. The association between orchid and fungi was observed as early as 1824, while the requirement for mycorrhiza for seed germination was established in 1899. An asymbiotic method for orchid seed germination was developed in 1921. After Knudson's media B and C were formulated, orchids growing and hybridization became widespread. Hybrids which early growers may not have even imagined became possible.

• Mycobiology
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• v.32 no.1
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• pp.42-46
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• 2004

Five fungicides such as rovral, bavistin, cupravit, dithane M-45 and thiovit were tested against conidial germination of Fusarium oxysporum. Dithane M-45 was the most effective against the fungus. Rests of the fungicides were more or less effective in the inhibition of conidial germination after $5{\sim}30$ minutes immersion in $500{\sim}2500$ ppm concentration. Five plant extracts(leaf extracts of Ocimum sanctum, Lantana camera, Calotropis procera, Azadirachta indica and Vinca rosea) found to be more or less effective against the fungus. 'Dhup' somke have good inhibitory effect on conidial germination of F. oxysporum.

• The Plant Pathology Journal
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• v.18 no.5
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• pp.288-292
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• 2002

Crude extract of Xanthium strumarium inhibited mycelial growth and zoospore germination of Phytophthora drechsleri, the causal agent of Atractylis rot, in vitro. Fresh sap from X. strumarium at 50-fold dilution was highly effective in controlling the disease Incidence in pot and field trials. Purified extracts from cocklebur Inhibited mycelial growth and zoospore germination in vitro at a concentration of 12.5 $\mu\textrm{g}$/ml and 15.6 $\mu\textrm{g}$/ml, respectively. Hyphal tips affected by the compound showed malformation. The antifungal compound puri- fied fromX. strumarium was identified as 4-oxo-1 (5), 2,11, (13)-xanthatriene-12,8-olide, known as "deacetyl xanthumin".min".uot;.

• Journal of Plant Biotechnology
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• v.43 no.1
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• pp.110-118
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• 2016

We compared germination efficiency for somatic embryos (SE) of Liriodendron tulipifera using semi-solid (SS), temporary immersion bioreactors (TIB), and continuous immersion bioreactors (CIB) to produce vigorous plants. The bioreactors were designed to be immersed in liquid media with plantlets with an adjustable immersion time. TIB and CIB improved germination rates up to 80.86% and 95.21%, respectively, however, CIB produced more hyperhydric plantlets than TIB. The height of plantlets in TIB was significantly higher than for those in CIB. Fresh weights of plantlets grown in CIB of were significantly lower than for those grown in TIB. The lowest chlorophyll concentration was found in in vitro plantlets from CIB. We examined abnormally developed leaves, stems, and apical zones of in vitro plantlets that were produced in CIB. Among the three types, SS showed the highest stomatal density and the shortest stomatal length in in vitro plantlets. After acclimatization, plants from CIB exhibited the lowest values in biomass, such as height, root collar diameter, leaf fresh weight, leaf length, leaf width, petiole length, petiole diameter, and leaf area. Photosynthesis and transpiration rates of ex vitro plants were not significantly different among the three culture types, but stomatal conductance was higher in TIB than in the SS and CIB. Therefore, the results suggest that TIB is the preferable bioreactor to improve in vitro plantlet regeneration of L. tulipifera. TIB-originated plants showed higher growth rate than SS and CIB after transferring to soil.

• Journal of Plant Biotechnology
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• v.5 no.3
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• pp.169-172
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• 2003

Somatic embryogenesis was initiated from in vitro grown leaf explants of rose following an induction period of four weeks on MS basal medium supplemented with auxin and several subcultures on MS medium with cytokinin. '4th of July' showed the highest regeneration frequencies on 1 mg/L NAA followed by culture on medium with 4 mg/L zeatin. The embryogenic callus was propagated on MS medium with NAA, zeatin and $GA_3$. Germination of somatic embryos was achieved on MS medium with 1 mg/L BA. Somatic embryo derived plantlets were hardened and successfully transferred to the greenhouse.

• Journal of Applied Biological Chemistry
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• v.49 no.4
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• pp.131-134
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• 2006

The in vitro anti-fungal activity of hydroxylated fatty acids obtained from microbial conversion by Psuedomonas aeruginosa PR3 using ricinoleic acid(RA), eicosadienoic acid(EDA) and conjugated linoleic acid(CLA) as substrates, was investigated. Bioconverted hydroxylated fatty acids showed different anti-fungal activities potentials against the range of phytopathogenic fungi such as Botrytis cinerea, Rhizoctonia solani, Fusarium oxysporum, Sclerotonia sclerotiorum, Colletotricum capsici, Fusarium solani and Phytophthora capsici. RA and EDA showed up to 50% fungal mycelial inhibition at the concentration of $5{\mu}l\;ml^{-1}$. RA, EDA and CLA also exhibited anti-fungal activities with minimum inhibitory concentration(MIC), ranging from 500 to $1000{\mu}g\;ml^{-1}$. Screening was also carried out using varied concentrations of bioconverted RA and EDA for determining the anti-fungal effect on the spore germination of different fungi. Bioconverted RA and EDA showed a considerable degree of spore germination inhibition.

• The Plant Pathology Journal
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• v.32 no.5
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• pp.469-480
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• 2016

Bacterial wilt and grey mould in tomato plants are economically destructive bacterial and fungal diseases caused by Ralstonia solanacearum and Botrytis cinerea, respectively. Various approaches including chemical and biological controls have been attempted to arrest the tomato diseases so far. In this study, in vitro growths of bacterial R. solanacearum and fungal B. cinerea were evaluated using four different vitamins including thiamine (vitamin B1), niacin (vitamin B3), pyridoxine (vitamin B6), and menadione (vitamin K3). In planta efficacies of the four vitamin treatments on tomato protection against both diseases were also demonstrated. All four vitamins showed different in vitro antibacterial activities against R. solanacearum in dose-dependent manners. However, treatment with 2 mM thiamine was only effective in reducing bacterial wilt of detached tomato leaves without phytotoxicity under lower disease pressure ($10^6$ colony-forming unit [cfu]/ml). Treatment with the vitamins also differentially reduced in vitro conidial germination and mycelial growth of B. cinerea . The four vitamins slightly reduced the conidial germination, and thiamine, pyridoxine and menadione inhibited the mycelial growth of B. cinerea. Menadione began to drastically suppress the conidial germination and mycelial growth by 5 and 0.5 mM, respectively. Grey mould symptoms on the inoculated tomato leaves were significantly reduced by pyridoxine and menadione pretreatments one day prior to the fungal challenge inoculation. These findings suggest that disease-specific vitamin treatment will be integrated for eco-friendly management of tomato bacterial wilt and grey mould.

• Current Research on Agriculture and Life Sciences
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• v.15
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• pp.47-52
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• 1997

The experiment was carried out to find the optimal condition for seed germination in vitro of Calanthe species. Seeds of Calanthe spp. after 90 days self pollination were well germinated in the MS medium. Germination condition of cross seeds between C. discolor and C. striata was much improved by pretreatment of micro sonic waves for 10 min. The days of germination was more shortened. and protocorm growth was more promoted in microsonic wave treatment than in non-treatment.

• Journal of Plant Biotechnology
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• v.48 no.4
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• pp.255-263
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• 2021

Paederia foetida L. is an important medicinal plant that has been used for the treatment of various gastrointestinal related ailments by different tribal communities in India. This plant is also known for its use as a food. Due to overexploitation, P. foetida has been classified as a vulnerable plant in some states of India. The propagation of P. foetida by conventional methods is easy but very slow. Synthetic seed technology offers incredible potential for in vitro propagation of threatened and commercially valuable plants, and can also facilitate the storage and exchange of axenic plant material between laboratories. However, synthetic seed production for P. foetida has not yet been reported. Thus, to the best of our knowledge, the present study is the first attempt to produce synthetic seeds of P. foetida by calcium alginate encapsulation of in vitro regenerated axenic nodal segments. Sodium alginate (3%) and CaCl₂ (100 mM) were found to be the optimal materials for the preparation of ideal synthetic seeds, both in terms of morphology and germination ability. The synthetic seeds showed the best germination (formation of both shoot as well as root; 83.3%) on ½ MS medium augmented with 0.5 mg/L indole-3-acetic acid. The plantlets obtained from these synthetic seeds could be successfully acclimatized under field conditions. We also studied the storage of these synthetic seeds at low temperature and their subsequent sprouting/germination. The seeds showed a germination rate of 63.3% even after 21 days of storage at 4 ℃; thus, they could be useful for transfer and exchange of P. foetida germplasm.

• Journal of Plant Biotechnology
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• v.39 no.3
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• pp.163-168
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• 2012

An optimization in vitro seed germination was established by using triphenol tetrazolium chloride (TTC) test, which has been known as two rare orchids (Gastrodia verrucosa Blume and Hetaeria sikokiana Tuyama) in Jeju island. We have established proper NaOCl treatment for in vitro germination of G. verrucosa and H. sikokiana through TTC test. In the case of H. sikokiana, seed viability through TTC test was high with 95% in control. However, NaOCl 1% treatment for 30 minutes showed the highest embryo swelling rate to seed viability. Likewise, swelling formation of embryos, diameter of embryos, protocorm formation and diameter of protocorms of G. verrucosa was 87%, $59{\mu}m$, 91% and $138{\mu}m$ through NaOCl 1% treatment for 30 minutes. This result will be applied on the basic information for improving in vitro seed germination rate of G. verrucosa and H. sikokiana.