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Meira Ziv

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Islamic Azad University, Semnan Branch

Shaheed Benazir bhutto university sheringal

King Saud University

SANDEEP KUMAR CHANDRAWANSHI

Indira Gandhi Krishi Vishwavidyalaya, Raipur

Lorenzo Borselli

Universidad Autónoma de San Luis Potosí

Herat University

Ohio State University

Stephen Mukembo

University of Missouri Columbia

Pere Verdés Pijuan

CSIC (Consejo Superior de Investigaciones Científicas-Spanish National Research Council)

Helmholtz Centre for Environmental Research

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Papers by Meira Ziv

The Effect of Gibberellin and Cytokinin on Floral Development in Zantedeschia Spp. In Vivo and in Vitro

Acta Horticulturae, 2005

Zantedeschia spp. (Araceae) is a tuberous day-neutral plant in which flowering is not induced by ... more Zantedeschia spp. (Araceae) is a tuberous day-neutral plant in which flowering is not induced by environmental signals. Flower yield, however, is increased by treatments with gibberellin A 3 or gibberellin A 4+7 and benzyl adenine (BA). We examined the effect of GA 3 and BA on inflorescence differentiation in three experimental systems: sprouting tubers, intact growing plants and plantlets in tissue culture. A similar pattern of response was found in all the experimental systems. One application of GA 3 resulted in inflorescence differentiation in the apical bud of the main shoot on the tuber as well as in plantlets in vitro. Continuous application of BA weakened apical dominance imposed by the main shoot and thus enabled the sprouting of inhibited axillary buds. Application of BA accompanied by one application of GA 3 resulted in inflorescence differentiation in the apical and axillary buds in the main and secondary shoots of the tuber as well as in plantlet in vitro. Thus, BA affected flowering indirectly by promoting axillary bud growth that responded to the GA 3 treatment. These results suggest that in day-neutral Zantedeschia the meristem is responsive to GA 3 regardless of tuber size, plant age, or meristem position. A change in GA 3 level may play a central role in the transition from the vegetative to the reproductive stage, and both gibberellins and cytokinins are involved in floral initiation and development. Plantlets in vitro can serve, therefore, as a model system for studying inflorescence development in day-neutral plants.

Expression of Viral Resistance in Transformed Petunia Plants Regenerated in Vitro

Acta Horticulturae, 2005

Vegetatively propagated trailing petunia is sensitve to virus infection. Attempts were made to de... more Vegetatively propagated trailing petunia is sensitve to virus infection. Attempts were made to develop a transformation protocol to introduce genes for virus resistance. Leaf segments from in vitro plants of two Cascadias varieties were cultured in vitro. Plants were regenerated from meristematic cell clusters that developed on segments cultured on a selected medium containing BA and NAA. Transformation was carried out with Agrobacterium. tumefaciens strains EHA105 and LBA4404. EHA105 carrying the plasmids pME504, pGA492PVY or pGA492PVYm and LBA4404 carrying pCMV N/B23, were used as a vector system for transformation. The plasmid pME504 carried the β-Glucuronidase (GUS) as a reporter gene and pGA492PVY carried the last three cistron of PVY (Protease-Replicase-Coat protein). The pGA492PVYm plasmid contained the same genes as described above with one distinction, the gene encoded the replicase had a mutation. The presence of acetosyringone during the incubation stage of the leaf segments increased the transformation efficiency. A total of 55 transgenic plants belonging to 55 independent lines transformed with a defective CMV replicase gene were challenged with CMV. Using the ELISA assay, two of the lines were found to be resistant to the virus while all the rest were susceptible. In addition, a total of 22 transgenic plants belong to 22 independent lines transformed with the plasmid pGA492PVY were also challenged by PVY. Using ELISA assay, two lines were found to have a delay in symptom development. A total of 23 transgenic plants transformed with the plasmid pGA492PVYM were also challenged by PVY. Using ELISA assay, only one line was found to be resistant to the virus. Southern blot analysis of resistant and susceptible transgenic plants showed the presence of the insert. The implication of these results is discussed.

Somatic Embryogenesis and Synthetic Seed in Apium graveolens (Celery)

Somatic Embryogenesis and Synthetic Seed II, 1995

Celery (Apium graveolens) is normally a biennial plant, but can complete its life cycle in a year... more Celery (Apium graveolens) is normally a biennial plant, but can complete its life cycle in a year if subjected to low temperatures. In the vegetative phase (the first year) the plant is composed mostly of petioles and leaves (60 cm in height), with a condensed shoot that does not elongate. The stem elongates during the second year, after vernalization, and the plant grows to 1–2 m in height. The stem terminates in a compound umbellate flower. Two types of celery are grown for commercial use: the green and the golden, self-balancing varieties.

Necrosis in grapevine buds (Vitis vinifera cv. Queen of Vineyard) III. Endogenous gibberellin levels in leaves and buds

The endogenous content of free and bound gibberellins (GA) in leaves and buds of Queen of Vineyar... more The endogenous content of free and bound gibberellins (GA) in leaves and buds of Queen of Vineyard grapevines was determined. Lateral buds on shoots from vigorous vines had about double the free GA activity of buds from less vigorous vines. No difference in the activity of bound GA was found. The GA content in the leaves of Queen of Vineyard was uniform, regardless of the vigor of the plants. The relation between vigor, GA content and bud necrosis in Queen of Vineyard vines is discussed and a causal dependence is suggested.

The Contribution of Biotechnology to Breeding, Propagation and Disease Resistance in Geophytes

Acta Horticulturae, 1997

Rescue of interspecific lents hybrids by means of embryo culture

Plant Cell Tissue and Organ Culture, 1984

Bud Regeneration and Growth from Transgenic and Non-Transgenic Aspen (Populus tremula) Root Explants

Biology of Root Formation and Development, 1997

Poplars, including aspen, (Populus tremula), are fast growing trees employed in the wood industry... more Poplars, including aspen, (Populus tremula), are fast growing trees employed in the wood industry and have a potential value for biomass and energy production. Vegetative propagation is carried out by cuttings, root suckers and grafting, but an increase of the propagation efficiency is highly desired. In vitro procedures are becoming available for efficient large-scale clonal propagation of poplar genotypes. These procedures can benefit from large-scale root culture in liquid media, based on the natural ability of aspen for shoot bud formation on roots (Carmi, 1994). The effect of different types of root expiants upon bud regeneration of aspen was studied using root segments from adventitious roots that formed on stem sections of two transgenic lines that harbored the rolB and rolC genes, and one non-transgeme line.

Reconsideration of the term ‘vitrification’ as used in micropropagation

Plant Cell, Tissue and Organ Culture, 1992

The term vitrification is currently used to describe two types of processes related to tissue-cul... more The term vitrification is currently used to describe two types of processes related to tissue-cultured plant material. The first is used to describe organs and tissues having an abnormal morphological appearance and physiological function. The second is used to describe the transition from liquid to solid state, i.e. the formation of ice during low temperature storage of in vitro cultured cells, tissues and organs. Use of the same term to define two greatly different processes in the same research area can only lead to confusion, especially for key words. Thus it is appropriate to reconsider the usage of vitrification in the first sense mentioned above. It is recommended that the term vitrification should no longer be used to indicate plant material with an abnormal morphological appearance and physiological function, and should be substituted by the term 'hyperhydricity'.

Multidimensional large deformation waves by the theory of characteristics

The Journal of the Acoustical Society of America, 1988

A presentation is given of solutions to multidimensional wave propagation in solids. These soluti... more A presentation is given of solutions to multidimensional wave propagation in solids. These solutions are obtained by a method based on the theory of characteristics. While for one-dimensional analysis a characteristics formulation suffices, it must be realized that multidimensional analysis necessitates two additional steps. First, the characteristics formulation must be extended to accommodate strong discontinuities. Second, the characteristics numerical integration must be confined to each region of influence encountered in the solution domain. For nonlinear material motions a third step is essential consisting of an all-events method of integration that mutates along the actual existing waves. Only then is adequate resolution reached for multidimensional wave propagation problems; the numerical results are then intrinsically stable and computer usage is minimal. Since, in the resultant deformation, the various wave fronts are explicitly revealed, physical interpretation is ensure...

Carbohydrate, metabolic, and osmotic changes in scaled-up liquid cultures of Narcissus leaves

In Vitro Cellular & Developmental Biology - Plant, 2003

Summary The use of scaled-up liquid cultures could be an efficient system for mass propagation of... more

Ancymidol-enhanced hyperhydric malformation in relation to gibberellin and oxidative stress in liquid-cultured Narcissus leaves

In Vitro Cellular & Developmental Biology - Plant, 2004

The growth retardant ancymidol inhibited gibberellin biosynthesis and enhanced hyperhydric malfor... more The growth retardant ancymidol inhibited gibberellin biosynthesis and enhanced hyperhydric malformation of Narcissus leaf sections cultured in liquid medium. Superoxide dismutase activities were examined by spectrophotometry and native polyacrylamide gel analysis, and gibberellin and hydrogen peroxide levels were determined spectrophotometrically in either hyperhydric or non-hyperhydric leaf sections. In ancymidol-treated hyperhydric leaf sections, superoxide dismutase activity and hydrogen peroxide levels were higher during the initial culture period, when hyperhydric malformation occurred, than in control untreated leaf sections. At a later stage, when the meristematic centers started to form on ancymidol-enhanced hyperhydric leaf sections, superoxide dismutase activity, hydrogen peroxide, and gibberellin levels were significantly lower in hyperhydric leaf sections than in non-treated leaf sections. The changes in superoxide dismutase activities, hydrogen peroxide, and gibberellin levels appeared to be related to hyperhydric malformation and meristematic center initiation.

Bud proliferation and plant regeneration in liquid-cultured philodendron treated with ancymidol and paclobutrazol

Journal of Plant Growth Regulation, 1991

... Paclobutrazol Meira Ziv l&amp;#x27;z and Tamar Ariel ... 1986) and gladiolus (Ziv 1989, 1... more

The use of growth retardants for the regulation and acclimatization of in vitro plants

Progress in Plant Growth Regulation, 1992

Plant cells in vitro are capable of regenerating whole plants affording biotechnology a novel met... more Plant cells in vitro are capable of regenerating whole plants affording biotechnology a novel method for mass propagation of several economic plants (Murashige, 1977). Agricultural application of plant micropropagation is often impeded by low proliferation rates and lack of modern methods to overcome labour intensive manipulations. Scaling-up in liquid cultures, together with automation can provide an efficient economic micropropagation system (Levin et al., 1988).

Imaging of Potato Shoots for Automated Mass Micropropagation

Morphogenic Pattern of Nephrolepis Exaltata CV. Bostoniensis in Agar or Liquid Cultures: Implications for Micropropagation

Israel journal of botany, 2013

In agar cultures, the morphogenic pattern of Nephrolepis exaltata cv. Bostoniensis shoot tips is ... more In agar cultures, the morphogenic pattern of Nephrolepis exaltata cv. Bostoniensis shoot tips is directed mainly toward leaf unfolding and growth. Submerged shoot tips or meristemoids in liquid cultures produced mostly meristemoid clusters, with limited leaf development. Aeration in liquid cultures, in rotated flasks, or in bubble bioreactors, neither enhanced leaf formation nor inhibited meristemoid development. Higher levels of agar in the medium resulted in a smaller number of meristemoids and a larger number of leaves developing on meristemoid aggregates initiated in liquid medium. Large-scale liquid cultures provided an efficient method for the production of meristemoid clusters in N. exaltata cv. Bostoniensis, which were then separated mechanically and developed into normal plants.

The Control of Bioreactor Environment for Plant Propagation in Liquid Culture

Acta Horticulturae, 1995

Regulation of Large Scale Embryogenesis in Celery

Acta Horticulturae, 1990

Pod Formation and Its Geotropic Orientation in the Peanut, Arachis hypogaea L., in Relation to Light and Mechanical Stimulus

Annals of Botany, 1976

ABSTRACT Gynophore elongation, pod formation and pod orientation in the peanut plant {Arachis hyp... more

Ethylene and the geotropic response of lateral branches in peanuts (<italic>Arachis hypogaea</italic> L.)

Plant and Cell Physiology, 1976

The prostrate growth habit of runner-type peanut plants changed when treated with the ethylene-re... more The prostrate growth habit of runner-type peanut plants changed when treated with the ethylene-releasing compound CEPA: the horizontal branches became plagiotropically oriented and the plant assumed a bushy form. Treatment with CEPA caused a marked increase in ethylene evolution for about a week, which then decreased to the level of the control. Nevertheless, the branches maintained their newly assumed plagiotropic orientation. Ethylene evolution from isolated branch tips correlated with their age and orientation, being highest in old plagiotropic and lowest in old diatropic branches. Light intensity and quality which caused plagiotropic orientation of branches also caused an increase in ethylene evolution, while ethylene evolution was lowest under light conditions favouring diatropic orientation. Along with the changes to plagiotropic orientation by CEPA, an increase in GA-like substances and a decrease in growth inhibitors was observed in extracts from treated plants.

Somatic Embryos and Bulblet Development from Bioreactor Regenerated Meristematic Clusters of Nerine

Acta Horticulturae, 1995

The Effect of Gibberellin and Cytokinin on Floral Development in Zantedeschia Spp. In Vivo and in Vitro

Acta Horticulturae, 2005

Zantedeschia spp. (Araceae) is a tuberous day-neutral plant in which flowering is not induced by ... more Zantedeschia spp. (Araceae) is a tuberous day-neutral plant in which flowering is not induced by environmental signals. Flower yield, however, is increased by treatments with gibberellin A 3 or gibberellin A 4+7 and benzyl adenine (BA). We examined the effect of GA 3 and BA on inflorescence differentiation in three experimental systems: sprouting tubers, intact growing plants and plantlets in tissue culture. A similar pattern of response was found in all the experimental systems. One application of GA 3 resulted in inflorescence differentiation in the apical bud of the main shoot on the tuber as well as in plantlets in vitro. Continuous application of BA weakened apical dominance imposed by the main shoot and thus enabled the sprouting of inhibited axillary buds. Application of BA accompanied by one application of GA 3 resulted in inflorescence differentiation in the apical and axillary buds in the main and secondary shoots of the tuber as well as in plantlet in vitro. Thus, BA affected flowering indirectly by promoting axillary bud growth that responded to the GA 3 treatment. These results suggest that in day-neutral Zantedeschia the meristem is responsive to GA 3 regardless of tuber size, plant age, or meristem position. A change in GA 3 level may play a central role in the transition from the vegetative to the reproductive stage, and both gibberellins and cytokinins are involved in floral initiation and development. Plantlets in vitro can serve, therefore, as a model system for studying inflorescence development in day-neutral plants.

Expression of Viral Resistance in Transformed Petunia Plants Regenerated in Vitro

Acta Horticulturae, 2005

Vegetatively propagated trailing petunia is sensitve to virus infection. Attempts were made to de... more Vegetatively propagated trailing petunia is sensitve to virus infection. Attempts were made to develop a transformation protocol to introduce genes for virus resistance. Leaf segments from in vitro plants of two Cascadias varieties were cultured in vitro. Plants were regenerated from meristematic cell clusters that developed on segments cultured on a selected medium containing BA and NAA. Transformation was carried out with Agrobacterium. tumefaciens strains EHA105 and LBA4404. EHA105 carrying the plasmids pME504, pGA492PVY or pGA492PVYm and LBA4404 carrying pCMV N/B23, were used as a vector system for transformation. The plasmid pME504 carried the β-Glucuronidase (GUS) as a reporter gene and pGA492PVY carried the last three cistron of PVY (Protease-Replicase-Coat protein). The pGA492PVYm plasmid contained the same genes as described above with one distinction, the gene encoded the replicase had a mutation. The presence of acetosyringone during the incubation stage of the leaf segments increased the transformation efficiency. A total of 55 transgenic plants belonging to 55 independent lines transformed with a defective CMV replicase gene were challenged with CMV. Using the ELISA assay, two of the lines were found to be resistant to the virus while all the rest were susceptible. In addition, a total of 22 transgenic plants belong to 22 independent lines transformed with the plasmid pGA492PVY were also challenged by PVY. Using ELISA assay, two lines were found to have a delay in symptom development. A total of 23 transgenic plants transformed with the plasmid pGA492PVYM were also challenged by PVY. Using ELISA assay, only one line was found to be resistant to the virus. Southern blot analysis of resistant and susceptible transgenic plants showed the presence of the insert. The implication of these results is discussed.

Somatic Embryogenesis and Synthetic Seed in Apium graveolens (Celery)

Somatic Embryogenesis and Synthetic Seed II, 1995

Celery (Apium graveolens) is normally a biennial plant, but can complete its life cycle in a year... more Celery (Apium graveolens) is normally a biennial plant, but can complete its life cycle in a year if subjected to low temperatures. In the vegetative phase (the first year) the plant is composed mostly of petioles and leaves (60 cm in height), with a condensed shoot that does not elongate. The stem elongates during the second year, after vernalization, and the plant grows to 1–2 m in height. The stem terminates in a compound umbellate flower. Two types of celery are grown for commercial use: the green and the golden, self-balancing varieties.

Necrosis in grapevine buds (Vitis vinifera cv. Queen of Vineyard) III. Endogenous gibberellin levels in leaves and buds

The endogenous content of free and bound gibberellins (GA) in leaves and buds of Queen of Vineyar... more The endogenous content of free and bound gibberellins (GA) in leaves and buds of Queen of Vineyard grapevines was determined. Lateral buds on shoots from vigorous vines had about double the free GA activity of buds from less vigorous vines. No difference in the activity of bound GA was found. The GA content in the leaves of Queen of Vineyard was uniform, regardless of the vigor of the plants. The relation between vigor, GA content and bud necrosis in Queen of Vineyard vines is discussed and a causal dependence is suggested.

The Contribution of Biotechnology to Breeding, Propagation and Disease Resistance in Geophytes

Acta Horticulturae, 1997

Rescue of interspecific lents hybrids by means of embryo culture

Plant Cell Tissue and Organ Culture, 1984

Bud Regeneration and Growth from Transgenic and Non-Transgenic Aspen (Populus tremula) Root Explants

Biology of Root Formation and Development, 1997

Poplars, including aspen, (Populus tremula), are fast growing trees employed in the wood industry... more Poplars, including aspen, (Populus tremula), are fast growing trees employed in the wood industry and have a potential value for biomass and energy production. Vegetative propagation is carried out by cuttings, root suckers and grafting, but an increase of the propagation efficiency is highly desired. In vitro procedures are becoming available for efficient large-scale clonal propagation of poplar genotypes. These procedures can benefit from large-scale root culture in liquid media, based on the natural ability of aspen for shoot bud formation on roots (Carmi, 1994). The effect of different types of root expiants upon bud regeneration of aspen was studied using root segments from adventitious roots that formed on stem sections of two transgenic lines that harbored the rolB and rolC genes, and one non-transgeme line.

Reconsideration of the term ‘vitrification’ as used in micropropagation

Plant Cell, Tissue and Organ Culture, 1992

The term vitrification is currently used to describe two types of processes related to tissue-cul... more The term vitrification is currently used to describe two types of processes related to tissue-cultured plant material. The first is used to describe organs and tissues having an abnormal morphological appearance and physiological function. The second is used to describe the transition from liquid to solid state, i.e. the formation of ice during low temperature storage of in vitro cultured cells, tissues and organs. Use of the same term to define two greatly different processes in the same research area can only lead to confusion, especially for key words. Thus it is appropriate to reconsider the usage of vitrification in the first sense mentioned above. It is recommended that the term vitrification should no longer be used to indicate plant material with an abnormal morphological appearance and physiological function, and should be substituted by the term 'hyperhydricity'.

Multidimensional large deformation waves by the theory of characteristics

The Journal of the Acoustical Society of America, 1988

A presentation is given of solutions to multidimensional wave propagation in solids. These soluti... more A presentation is given of solutions to multidimensional wave propagation in solids. These solutions are obtained by a method based on the theory of characteristics. While for one-dimensional analysis a characteristics formulation suffices, it must be realized that multidimensional analysis necessitates two additional steps. First, the characteristics formulation must be extended to accommodate strong discontinuities. Second, the characteristics numerical integration must be confined to each region of influence encountered in the solution domain. For nonlinear material motions a third step is essential consisting of an all-events method of integration that mutates along the actual existing waves. Only then is adequate resolution reached for multidimensional wave propagation problems; the numerical results are then intrinsically stable and computer usage is minimal. Since, in the resultant deformation, the various wave fronts are explicitly revealed, physical interpretation is ensure...

Carbohydrate, metabolic, and osmotic changes in scaled-up liquid cultures of Narcissus leaves

In Vitro Cellular & Developmental Biology - Plant, 2003

Summary The use of scaled-up liquid cultures could be an efficient system for mass propagation of... more

Ancymidol-enhanced hyperhydric malformation in relation to gibberellin and oxidative stress in liquid-cultured Narcissus leaves

In Vitro Cellular & Developmental Biology - Plant, 2004

The growth retardant ancymidol inhibited gibberellin biosynthesis and enhanced hyperhydric malfor... more The growth retardant ancymidol inhibited gibberellin biosynthesis and enhanced hyperhydric malformation of Narcissus leaf sections cultured in liquid medium. Superoxide dismutase activities were examined by spectrophotometry and native polyacrylamide gel analysis, and gibberellin and hydrogen peroxide levels were determined spectrophotometrically in either hyperhydric or non-hyperhydric leaf sections. In ancymidol-treated hyperhydric leaf sections, superoxide dismutase activity and hydrogen peroxide levels were higher during the initial culture period, when hyperhydric malformation occurred, than in control untreated leaf sections. At a later stage, when the meristematic centers started to form on ancymidol-enhanced hyperhydric leaf sections, superoxide dismutase activity, hydrogen peroxide, and gibberellin levels were significantly lower in hyperhydric leaf sections than in non-treated leaf sections. The changes in superoxide dismutase activities, hydrogen peroxide, and gibberellin levels appeared to be related to hyperhydric malformation and meristematic center initiation.

Bud proliferation and plant regeneration in liquid-cultured philodendron treated with ancymidol and paclobutrazol

Journal of Plant Growth Regulation, 1991

... Paclobutrazol Meira Ziv l&amp;#x27;z and Tamar Ariel ... 1986) and gladiolus (Ziv 1989, 1... more

The use of growth retardants for the regulation and acclimatization of in vitro plants

Progress in Plant Growth Regulation, 1992

Plant cells in vitro are capable of regenerating whole plants affording biotechnology a novel met... more Plant cells in vitro are capable of regenerating whole plants affording biotechnology a novel method for mass propagation of several economic plants (Murashige, 1977). Agricultural application of plant micropropagation is often impeded by low proliferation rates and lack of modern methods to overcome labour intensive manipulations. Scaling-up in liquid cultures, together with automation can provide an efficient economic micropropagation system (Levin et al., 1988).

Imaging of Potato Shoots for Automated Mass Micropropagation

Morphogenic Pattern of Nephrolepis Exaltata CV. Bostoniensis in Agar or Liquid Cultures: Implications for Micropropagation

Israel journal of botany, 2013

In agar cultures, the morphogenic pattern of Nephrolepis exaltata cv. Bostoniensis shoot tips is ... more In agar cultures, the morphogenic pattern of Nephrolepis exaltata cv. Bostoniensis shoot tips is directed mainly toward leaf unfolding and growth. Submerged shoot tips or meristemoids in liquid cultures produced mostly meristemoid clusters, with limited leaf development. Aeration in liquid cultures, in rotated flasks, or in bubble bioreactors, neither enhanced leaf formation nor inhibited meristemoid development. Higher levels of agar in the medium resulted in a smaller number of meristemoids and a larger number of leaves developing on meristemoid aggregates initiated in liquid medium. Large-scale liquid cultures provided an efficient method for the production of meristemoid clusters in N. exaltata cv. Bostoniensis, which were then separated mechanically and developed into normal plants.

The Control of Bioreactor Environment for Plant Propagation in Liquid Culture

Acta Horticulturae, 1995

Regulation of Large Scale Embryogenesis in Celery

Acta Horticulturae, 1990

Pod Formation and Its Geotropic Orientation in the Peanut, Arachis hypogaea L., in Relation to Light and Mechanical Stimulus

Annals of Botany, 1976

ABSTRACT Gynophore elongation, pod formation and pod orientation in the peanut plant {Arachis hyp... more

Ethylene and the geotropic response of lateral branches in peanuts (<italic>Arachis hypogaea</italic> L.)

Plant and Cell Physiology, 1976

The prostrate growth habit of runner-type peanut plants changed when treated with the ethylene-re... more The prostrate growth habit of runner-type peanut plants changed when treated with the ethylene-releasing compound CEPA: the horizontal branches became plagiotropically oriented and the plant assumed a bushy form. Treatment with CEPA caused a marked increase in ethylene evolution for about a week, which then decreased to the level of the control. Nevertheless, the branches maintained their newly assumed plagiotropic orientation. Ethylene evolution from isolated branch tips correlated with their age and orientation, being highest in old plagiotropic and lowest in old diatropic branches. Light intensity and quality which caused plagiotropic orientation of branches also caused an increase in ethylene evolution, while ethylene evolution was lowest under light conditions favouring diatropic orientation. Along with the changes to plagiotropic orientation by CEPA, an increase in GA-like substances and a decrease in growth inhibitors was observed in extracts from treated plants.

Somatic Embryos and Bulblet Development from Bioreactor Regenerated Meristematic Clusters of Nerine

Acta Horticulturae, 1995