In vitro testing of defense reactions in zygotic and somatic embryos of Abies numidica

Defense of desiccated cotyledonary somatic embryos and mature zygotic embryos of Abies numidica was tested in vitro by dual cultures with tester, fungus Phaeolus schweinitzii. Both types of embryos expressed defense reactions manifested by inhibited growth of fungal tester towards the embryos. Mycelial growth was described by logistic sigmoid growth model with a single asymptote. Mutual comparisons of mycelial growth in presence of zygotic and somatic embryos showed significant differences in parameters of mycelium growth curves towards the embryos. Larger defense reactions were observed in zygotic embryos relative to somatic embryos and unlimited control cultivations without embryo. The possible role of auxin in the defense response of plant embryos is discussed.

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Testing of Algerian fir zygotic and somatic embryos on defence reactions in vitro

Plant Soil and Environment ◽

10.17221/237/2011-pse ◽

2012 ◽

Vol 58 (No. 2) ◽

pp. 84-90

Author(s):

B. Vooková ◽

J. Hřib ◽

V. Adamec

Keyword(s):

Somatic Embryos ◽

Mycelial Growth ◽

Zygotic Embryos ◽

Dual Cultures ◽

Defence Reactions ◽

Algerian Fir

Defence reactions of desiccated cotyledonary somatic embryos and mature zygotic embryos of Abies numidica were tested by dual cultures with tester, fungus Phaeolus schweinitzii. Both types of embryos expressed defence reactions. Mutual comparisons of zygotic and somatic embryos showed important differences between defence reactions against mycelial growth towards these embryos. Greater defence reactions were observed in zygotic embryos relative to defence found in somatic embryos.  

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Soybean galactinol synthase forms fagopyritol B1 but not galactopinitols: substrate feeding of isolated embryos and heterologous expression

Seed Science Research ◽

10.1079/ssr2004186 ◽

2004 ◽

Vol 14 (4) ◽

pp. 321-333 ◽

Cited By ~ 22

Author(s):

Ralph L. Obendorf ◽

Silvia Odorcic ◽

Takashi Ueda ◽

Mark P. Coseo ◽

Elizabeth Vassallo

Keyword(s):

Somatic Embryos ◽

Sucrose Concentration ◽

Soluble Carbohydrates ◽

Zygotic Embryos ◽

Substrate Availability ◽

Galactinol Synthase ◽

Substrate Feeding ◽

Inositol Uptake

Soybean (Glycine max (L.) Merrill) seeds accumulate sucrose, raffinose, stachyose and lesser amounts of galactopinitol A, galactopinitol B and fagopyritol B1 in axis and cotyledon tissues as part of the seed maturation process. Somatic embryos appear to be deficient in D-pinitol and galactopinitols, indicating a lack of synthesis by embryo tissues in vitro. Isolated immature soybean zygotic embryos were fed myo-inositol, D-pinitol, D-chiro-inositol and sucrose, individually and in combination, to evaluate the role of substrate availability on galactosyl cyclitol accumulation during precocious maturation. Feeding myo-inositol transiently doubled galactinol accumulation with little effect on other soluble carbohydrates. Feeding D-pinitol increased free D-pinitol 8-fold, galactopinitol A 4.5-fold and galactopinitol B 4.2-fold. Stachyose concentration was 2-fold higher in cotyledons after feeding D-pinitol than after feeding D-chiro-inositol. Feeding D-chiro-inositol increased fagopyritol B1 17-fold in the axis and 7-fold in the cotyledons, but did not increase other soluble carbohydrates. Feeding D-pinitol and D-chiro-inositol together reduced uptake of D-chiro-inositol and steady-state accumulation of galactinol and galactopinitols by 50%, compared to feeding D-pinitol alone. Increasing sucrose concentration from 0 to 200 mM had no effect. Recombinant soybean galactinol synthase, heterologously expressed in Escherichia coli, catalysed the synthesis of fagopyritol B1 and galactinol, but not galactopinitols. These results were consistent with the following interpretations: D-pinitol and D-chiro-inositol were transported from maternal tissues and not synthesized in the embryo, D-chiro-inositol uptake into embryos may be reduced by D-pinitol, fagopyritol B1 was synthesized by galactinol synthase while galactopinitols were not, and fagopyritol B1 and galactopinitols accumulated in response to the supply of free D-chiro-inositol and D-pinitol to embryos.

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Diffusible Compounds Produced by Hanseniaspora osmophila and Gluconobacter cerinus Help to Control the Causal Agents of Gray Rot and Summer Bunch Rot of Table Grapes

Antibiotics ◽

10.3390/antibiotics10060664 ◽

2021 ◽

Vol 10 (6) ◽

pp. 664

Author(s):

Matías Olivera ◽

Ninoska Delgado ◽

Fabiola Cádiz ◽

Natalia Riquelme ◽

Iván Montenegro ◽

...

Keyword(s):

Mycelial Growth ◽

Inhibitory Effect ◽

Biocontrol Agents ◽

Environmental Cost ◽

Antifungal Compounds ◽

Table Grapes ◽

Dual Cultures ◽

Bunch Rot ◽

Direct Bioautography

Gray and summer bunch rot are important diseases of table grapes due to the high economic and environmental cost of their control with synthetic fungicides. The ability to produce antifungal compounds against the causal agents Botrytis, Aspergillus, Penicillium, and Rhizopus of two microorganisms isolated from table grapes and identified as Hanseniaspora osmophila and Gluconobacter cerinus was evaluated. In dual cultures, both biocontrol agents (together and separately) inhibited in vitro mycelial growth of these pathogens. To identify the compounds responsible for the inhibitory effect, extractions were carried out with organic solvents from biocontrol agents separately. Through dual cultures with pathogens and pure extracts, only the hexane extract from H. osmophila showed an inhibitory effect against Botrytis cinerea. To further identify these compounds, the direct bioautography technique was used. This technique made it possible to determine the band displaying antifungal activity at Rf = 0.05–0.2. The compounds present in this band were identified by GC-MS and compared to the NIST library. The most abundant compounds, not previously reported, corresponded to alkanes, ketones, alcohols, and terpenoids. H. osmophila and G. cerinus have the potential to control the causal agents of gray and summer bunch rot of table grapes.

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AVALIAÇÃO DO REAL POTENCIAL INIBIDOR DE EXTRATOS ETANÓLICOS DE Ottonia martiana SOBRE Cylindrocladium spathulatum E Botrytis cinerea

FLORESTA ◽

10.5380/rf.v43i2.20199 ◽

2013 ◽

Vol 43 (2) ◽

pp. 225

Author(s):

Miriam Machado Cunico ◽

Celso Garcia Auer ◽

Marlon Wesley Machado Cunico ◽

Obdulio Gomes Miguel ◽

Patricio Peralta Zamora ◽

...

Keyword(s):

Factorial Design ◽

Botrytis Cinerea ◽

Mycelial Growth ◽

Black Spot ◽

Gray Mold ◽

Causal Agent ◽

In Vitro Testing ◽

Ethanolic Extracts ◽

Antifungal Potential

Extratos etanólicos de anestesia, Ottonia martiana Miq., foram reavaliados quanto à inibição do crescimento micelial dos fungos Cylindrocladium spathulatum (pinta-preta da erva-mate) e Botrytis cinerea (mofo-cinzento do eucalipto), por meio do planejamento fatorial. A ocorrência de decomposição de bioativos no processo de autoclavagem também foi investigada, por meio de teste de eficiência de extratos filtrados (filtro Millipore) e esterilizados (autoclave) no controle dos fitopatógenos, nas concentrações de 1, 10, 100 e 1000 ppm. Os extratos etanólicos filtrado e esterilizado inibiram o crescimento micelial dos fungos e foram mais ativos frente a B. cinerea.O extrato filtrado exibiu maior potencial antifúngico que o extrato esterilizado. O processo de esterilização por autoclavagem causou pequena decomposição dos bioativos presentes no extrato de anestesia.Palavras-chave: Anestesia; mofo-cinzento; pinta-preta. Abstract Fungitoxic potential of ethanolic extracts of anestesia in the control of phytopathogenic diseases. The antifungal potential of anestesia, Ottonia martiana Miq. was reassessed by factorial design, in vitro testing of fungal mycelial growth compared to the pathogenic isolates Cylindrocladium spathulatum, causal agent of black spot onyerba mate, and Botrytis cinerea causal agent of gray-mold on eucalypts. Occurrence of decomposition of bioactive of the autoclaving process was investigated using foliar detached test compared to the pathogens (1000 ppm). Ethanolic extracts - EBEtOH (filtered and autoclaved) inhibited the mycelial growth of C. spathulatum and B. cinerea (1000 ppm) and were more pronounced against B. cinerea (43.6 % and 68.9 %). EBEtOH filtered (0.22 µm) presented higher activity than EBEtOH autoclaved (C. spathulatum: 52.8 % and 43.6 %, B. cinerea: 68.9 % and 43.6 %), suggesting little decomposition ofbioactive after autoclaving. EBEtOH filtrate presented potential inhibition of 28 % in eucalypt leaves against B. cinerea. Keywords: Ottonia martiana; black spot; gray-mold.

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In vitro evaluation of fungal antagonists of Phytophthora nicotianae

Plant Protection Science ◽

10.17221/10577-pps ◽

2017 ◽

Vol 38 (SI 2 - 6th Conf EFPP 2002) ◽

pp. 634-637

Author(s):

R. Nicoletti ◽

F. Raimo ◽

E. Cozzolino

Keyword(s):

Mycelial Growth ◽

Central Italy ◽

Phytophthora Nicotianae ◽

Aspergillus Sydowii ◽

Black Shank ◽

Culture Filtrates ◽

Dual Cultures ◽

Penicillium Brevicompactum ◽

Fusarium Chlamydosporum

As tobacco black shank epidemics caused by Phytophthora nicotianae occurred in central Italy in the late 1990s, fungal antagonists of the pathogen were searched in the rhizosphere of tobacco plants. Isolates of Aspergillus sydowii, Fusarium chlamydosporum, Gliocladium roseum, Penicillium brevicompactum, P. chrysogenum, Scopulariopsis candida and Trichoderma harzianum were recovered. Antagonism of these isolates toward P. nicotianae was evaluated in vitro: even if no hyphal interactions were observed in dual cultures, aberration in mycelial growth and morphology of sporangia occurred in most cases. Unlike those of T. harzianum, concentrated culture filtrates of A. sydowii, F. chlamydosporum, G. roseum, P. brevicompactum, P. chrysogenum, inhibited growth of all P. nicotianae isolates tested, while culture filtrates of S. candida caused aberrant mycelial growth.

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Blue sky’s the limit? Somatic embryogenesis as a means of propagating recalcitrant blue spruce (Picea pungens) cultivar Hoopsii

10.1101/700518 ◽

2019 ◽

Author(s):

Jordan Demone ◽

Jingqin Mao ◽

Shen Wan ◽

Maryam Nourimand ◽

Äsbjörn Erik Hansen ◽

...

Keyword(s):

Somatic Embryogenesis ◽

Somatic Embryos ◽

Growing Season ◽

Zygotic Embryos ◽

Embryo Abortion ◽

Blue Spruce ◽

Picea Pungens ◽

Initiation Frequency ◽

Propagation Methods

AbstractThe ‘triple-blue’ cultivar of blue spruce (Picea pungens Hoopsii) is notably recalcitrant towards the realm of traditional vegetative propagation methods. Its ability to naturally proliferate is limited by ovule and embryo abortion during the growing season, leading to low viable seed yield. In this study, we established a protocol using somatic embryogenesis (SE) as a means of propagating this popular ornamental cultivar. We collected cones from Hoopsii trees at seven different timepoints throughout the growing season (mid-June to late July in Ottawa (Plant Hardiness Zone 5A)). Female megagametophytes were harvested following each collection and immature zygotic embryos were plated onto induction media. Early somatic embryos began developing from the embryonic tissue (ET) three to five weeks following induction. The highest ET initiation frequency occurred from embryos collected June 20–July 10, suggesting that developmental stage of the embryo was a significant factor in SE induction. The conversion of mature somatic embryos into plantlets (emblings) was completed in eight–ten weeks at a rate of 92.8%. In this study, we demonstrate that in vitro somatic embryogenesis using our optimized protocol is a fast and prolific method for the mass propagation of Hoopsii blue spruce. This is the first report on the production of somatic Hoopsii emblings.

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Coconut Tissue Culture: The Indian Initiatives, Experiences and Achievements

CORD ◽

10.37833/cord.v33i2.48 ◽

2017 ◽

Vol 33 (2) ◽

pp. 11

Author(s):

Anitha Karun

Keyword(s):

Tissue Culture ◽

Somatic Embryos ◽

Culture Media ◽

Zygotic Embryo ◽

Shoot Meristem ◽

Direct Organogenesis ◽

Zygotic Embryos ◽

Immature Inflorescence ◽

High Yielding Varieties

Coconut is one of the principal crops of India cultivated in over 35 districts mainly in the southern states. The productivity of the crop is declining in many of the traditionally cultivated regions owing to ageing plantations as well as biotic and abiotic stresses. These plantations are to be replanted with high yielding varieties/hybrids for which adequate quantity of quality planting material is not available. Even though tissue culture research was initiated in many laboratories in the country, the work was eventually phased out in most of the laboratories for want of a repeatable protocol. At ICAR-CPCRI, coconut tissue culture programs have been continuing for the past three decades. The attempts made include experimentation with different explants viz., immature inflorescence, plumular tissues, mature palm shoot meristem, ovary and anthers and different culture media supplemented with varying levels and types of hormones. Some of the successful protocols developed at the Institute include coconut zygotic embryo culture for collection and exchange of germplasm, cryopreservation and retrieval of zygotic embryos and pollen and plantlet regeneration from plumular tissues. Even though ICAR-CPCRI has succeeded in obtaining plantlets via direct organogenesis from inflorescence explants, the absence of friable calli formation from explants, the low rate of somatic embryo formation, large number of cultures turning to abnormal shoot development, non conversion of somatic embryos into plantlets, and formation of abnormal somatic embryos remain the major bottlenecks. Gene expression studies are being currently undertaken to decipher the molecular basis of in vitro recalcitrance.

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Effects of methyl jasmonate and gums formed in stone fruit trees on in vitro ethylene production by mycelium of verticillium dahliae and alternaria alternata

Journal of Horticultural Research ◽

10.2478/johr-2013-0026 ◽

2013 ◽

Vol 21 (2) ◽

pp. 87-93

Author(s):

Elżbieta Węgrzynowicz-Lesiak ◽

Anna Jarecka Boncela ◽

Justyna Góraj ◽

Marian Saniewski

Keyword(s):

Methyl Jasmonate ◽

Verticillium Dahliae ◽

Ethylene Production ◽

Alternaria Alternata ◽

Pathogenic Fungi ◽

Fruit Trees ◽

Stone Fruit ◽

Mycelium Growth

ABSTRACT The knowledge about the role of jasmonates in ethylene production by pathogenic fungi is ambiguous. In this study, we describe the effect of methyl jasmonate (JA-Me) and gums formed in stone fruit trees on the growth and in vitro ethylene production by mycelium of Verticillium dahliae and Alternaria alternata. Methyl jasmonate at concentrations of 100, 250 and 500 μg·cm-3 inhibited the mycelium growth of V. dahliae and A. alternata, proportionally to the concentrations used. After 8 days of incubation, JA-Me at concentration of 500 μg·cm-3 limited the area of mycelium of these pathogens by 7-8 times but did not entirely inhibited the pathogen growth. Addition of gums produced by trees of cherry and peach to a medium containing 40 μg·cm-3 JA-Me did not influence the mycelium growth of V. dahliae, but gums of plum and apricot trees stimulated mycelium growth, in comparison to JA-Me only. Methyl jasmonate at concentrations of 2 and 40 μg·cm-3 stimulated the ethylene production by mycelium of V. dahliae and A. alternata. It is possible that methyl jasmonate stimulated ethylene production in mycelium of these pathogens through interaction with some fractions of galactans formed during hydrolysis of agar. The lack of interaction of JA-Me with polysaccharides of stone fruit trees gums concerning ethylene production was documented and it needs further explanation.

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Somatic Embryogenesis using Immature Zygotic Embryos from Developing Fruits of Papaya (Carica papaya)

HortScience ◽

10.21273/hortsci.30.4.783e ◽

1995 ◽

Vol 30 (4) ◽

pp. 783E-783

Author(s):

S.K. Dhir ◽

U.L. Yadava

Keyword(s):

Somatic Embryogenesis ◽

Somatic Embryos ◽

Carica Papaya ◽

Induction Medium ◽

Zygotic Embryos ◽

Synthetic Seed ◽

Factors Affecting ◽

Secondary Embryos ◽

Potential Use

An efficient protocol has been developed for the in vitro multiplication of papaya (Carica papaya L.) through somatic embryogenesis utilizing immature zgotic embryos. Somatic embryos were initiated on MS basel media supplemented with 5 mg·liter–1 2,4-D, 400 mg·liter–1 glutamine, and 6% sucrose. After culturing for 2 months, 65% of the explants became highly embryogenic. Each explant produced 50 to 80 embryos in 4 months on culture induction medium. Frequency of embryogenesis was increased (75 to 150 somatic embryos on 80% explants) upon supplementing medium with 4% maltose as a carbon source and 100 mg·liter–1 L-asparagine. The embryogenic callus appeared yellow and embryos at different stages of development were well-organized. On regular subculturing, these cultures continued to produce secondary embryos. Following their transfer to the hormone-free medium supplemented with 4% maltose, these embryos germinated. The somatic embryogenesis system is rapid, repetitive, and highly proliferative. Thus, this system may have a potential use in the development of synthetic seed and transgenic papaya plants. Details of important factors affecting somatic embryogenesis will be discussed.

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Antibiotic combinations: should they be tested?

Clinical Microbiology Reviews ◽

10.1128/cmr.1.2.139 ◽

1988 ◽

Vol 1 (2) ◽

pp. 139-156 ◽

Cited By ~ 97

Author(s):

G M Eliopoulos ◽

C T Eliopoulos

Keyword(s):

Antimicrobial Activity ◽

Animal Models ◽

Screening Methods ◽

In Vitro Testing ◽

Synergistic Interactions ◽

Human Infections ◽

Antibiotic Interactions ◽

Synergy Testing

When antibiotic combinations are used to provide a broader spectrum of antimicrobial activity or in an attempt to prevent the emergence of resistant organisms, it is rarely necessary or practical to perform tests of drug interactions in vitro. In vitro testing of combinations may be useful when combinations are used in an attempt to attain synergistic interactions. In some cases, screening methods can be used as substitutes for formal synergy testing. This paper examines the mechanisms of antibiotic interaction leading to synergism or antagonism, surveys attempts to correlate in vitro observations with efficacy in animal models, and reviews clinical data providing evidence for or against a useful role of synergistic antibiotic interactions in the treatment of human infections.

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