Yaser Dewir | Kafrelsheikh University (original) (raw)

Papers by Yaser Dewir

Research paper thumbnail of Flowering of Euphorbia millii Plantlets In Vitro as Affected by Paclobutrazol, Light Emitting Diodes (LEDs) and Sucrose

Acta Horticulturae, 2007

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Nutrient utilization during in vitro flowering of Spathiphyllum (Poster presentation)

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Biochemical and Physiological Aspects of Hyperhydricity in Liquid Culture System

ABSTRACT Large-scale liquid cultures and automation have proven the potential to resolve manual h... more ABSTRACT Large-scale liquid cultures and automation have proven the potential to resolve manual handling of in vitro cultures at various stages and decreases production cost. However, hyperhydricity is a major problem during in vitro culture of many crops in liquid culture systems. The environment inside culture vessel normally used in plant micropropagation is characterized by high humidity, limited gaseous exchange between the internal atmosphere of the culture vessel and its surrounding environment, and the accumulation of ethylene, conditions that may induce physiological disorders. Hyperhydricity is a disorder of tissue-cultured plants where leaves become translucent and stems swollen, distorted and brittle. Although numerous hypotheses have been put forward to explain hyperhydricity but there is still a lack of knowledge about the nature of signals responsible for hyperhydricity and the metabolic processes which are affected by its development. The concept of stress in relation to hyperhydricity is not completely established. Therefore, it remains difficult to assume that hyperhydric tissues are stressed. Previous studies argued that abnormal morphology observed in hyperhydricity could be attributed to changes occurring at cellular level due to the modifications of membrane composition or DNA content. In order to understand stress and morphological responses in hyperhydric tissues, in the present article, we are reviewing different biochemical and physiological mechanisms of hyperhydricity in several plant species.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Indirect shoot organogenesis and plantlets regeneration from stem of ornamental Dieffenbachia maculata cv. Marianna

Acta Biologica Szegediensis, 2007

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Effect of Light-Emitting Diode on Growth and Shoot Proliferation of Euphorbia millii and Spathiphyllum cannifolium

Horticulture Environment and Biotechnology, 2005

Bookmarks Related papers MentionsView impact

Research paper thumbnail of 埃及古代农业的历史

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Physiological responses of suspension-cultured Carnation cells to gamma rays irradiation and high temperature stress 辐射和高温胁迫康乃馨悬浮培养细胞生长的影响

RefDoc Bienvenue - Welcome. Refdoc est un service / is powered by. ...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Flowering of Euphorbia Millii Plantlets in Vitro as Affected by Paclobutrazol, Light Emitting Diodes (Leds) and Sucrose

Acta Horticulturae, 2007

Bookmarks Related papers MentionsView impact

Research paper thumbnail of In Vitro Flowering of Spathiphyllum Cannifolium: Influences of Gibberellic Acid, Culture Type and Sucrose Concentration

Acta Horticulturae, 2006

ABSTRACT

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Factors affecting ex vitro rooting and growth of Spathiphyllum plantlets in the microponic culture system

Wonye kwahak kisulchi = Korean journal of horticultural science and technology /

Bookmarks Related papers MentionsView impact

Research paper thumbnail of In vitro flowering of Sathiphyllum cannifolium: Influences of gibberellic acid, culture type and sucrose concentration

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Ornamental Euphorbia and Spathiphyllum: Application of Bioreactor System and Microponics for Large-scale Production, In vitro Flowering and its Physiology

ABSTRACT

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Hyperhydricity: stress related phenomenon?

Wonye kwahak kisulchi = Korean journal of horticultural science and technology /

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Weight loss and antioxidants degradation in spears of five asparagus cultivars during cold and freeze storage

Australian Journal of Crop Science

Asparagus (Asparagus officinalis L) is considered as a vegetable rich in antioxidants. The presen... more Asparagus (Asparagus officinalis L) is considered as a vegetable rich in antioxidants. The present study investigated and compared the weight loss and degradation of antioxidants including ascorbic acid (ASC), glutathione (GSH) and cysteine (CYS) in spears of five asparagus cultivars (Bonlim, Eposs, Mars, Thielim and Vulkan). Spears were stored either under cold storage at 4 °C for 12 days or were deep frozen at - 20 °C for 12 months. The results showed that there are significant differences among asparagus cultivars with respect to their weight loss and antioxidants content of ASC, GSH and CYS. Weight loss and degradation of antioxidants were increased with increasing storage duration. At the end of 12 days period of cold storage, the cultivar Eposs showed the highest weight loss with 3.14%, while for the cultivar Vulkan, the lowest weight loss with 2.14% was recorded. When spears were deep frozen, the weight loss was lower than that recorded under cold storage. After 6 months of s...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of The control of in vitro flowering and association of glutathione metabolism

Floral transition is a complex biological event in the life cycle of flowering plants. In vitro c... more Floral transition is a complex biological event in the life cycle of flowering plants. In vitro culture techniques have important applications towards understanding the flowering process. A single parameter can be investigated to assess its effect on flowering. Investigations on this nature have focused upon the manipulation of media components and culture conditions. Approximately eight decades of in vitro flowering research has been conducted, however, it is difficult to predict how and when flower is to be initiated. This chapter describes various factors controlling in vitro flowering with emphasis on recent findings. The reviewed studies show that in vitro flowering can provide a model system for studying the “switch-on” flowering mechanism and provide means for conducting in vitro breeding. In addition, other applications include; production of early flowering pot plants for commercial market as well as test tube bouquets. The focus of this chapter highlights the relationship ...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Hyperhydricity in African violet (Saintpaulia ionantha H. Wendl) – biochemical aspects of normal versus hyperhydric shoots regenerated via direct adventitious shoots formation

PROPAGATION OF ORNAMENTAL PLANTS

African violet (Saintpaulia ionantha H. Wendl) is one of the most easily and commonly tissue-cult... more African violet (Saintpaulia ionantha H. Wendl) is one of the most easily and commonly tissue-cultured ornamental plants. Despite this, there are limited reports on the direct adventitious shoots from any organ, most papers reporting on an indirect route through callus. In this study, adventitious shoots were induced directly from leaf and petiole explants from in vitro plantlets derived from shoot tip culture. Murashige and Skoog (MS) medium supplemented with 0.2 mg l-1 6-benzyladenine and 0.1 mg l-1 kinetin resulted in 91.65% direct shoot formation from leaf explants and 70% from petiole explants while 32.5 and 17.5 shoots formed per leaf and petiole explant, respectively. The origin of shoots was histologically demonstrated. The potential role of antioxidant enzymes in protecting hyperhydric plantlets from oxidative injury was examined by analyzing antioxidant enzyme activities of hyperhydric and normal tissues. Activities of catalase (CAT), peroxidase (POD), polyphenol oxidase (P...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Biochemical and Physiological Aspects of Hyperhydricity in Liquid Culture System

Production of Biomass and Bioactive Compounds Using Bioreactor Technology, 2014

ABSTRACT Large-scale liquid cultures and automation have proven the potential to resolve manual h... more ABSTRACT Large-scale liquid cultures and automation have proven the potential to resolve manual handling of in vitro cultures at various stages and decreases production cost. However, hyperhydricity is a major problem during in vitro culture of many crops in liquid culture systems. The environment inside culture vessel normally used in plant micropropagation is characterized by high humidity, limited gaseous exchange between the internal atmosphere of the culture vessel and its surrounding environment, and the accumulation of ethylene, conditions that may induce physiological disorders. Hyperhydricity is a disorder of tissue-cultured plants where leaves become translucent and stems swollen, distorted and brittle. Although numerous hypotheses have been put forward to explain hyperhydricity but there is still a lack of knowledge about the nature of signals responsible for hyperhydricity and the metabolic processes which are affected by its development. The concept of stress in relation to hyperhydricity is not completely established. Therefore, it remains difficult to assume that hyperhydric tissues are stressed. Previous studies argued that abnormal morphology observed in hyperhydricity could be attributed to changes occurring at cellular level due to the modifications of membrane composition or DNA content. In order to understand stress and morphological responses in hyperhydric tissues, in the present article, we are reviewing different biochemical and physiological mechanisms of hyperhydricity in several plant species.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Influences of explant type and enzyme incubation on isolated protoplast density and viability in two garlic cultivars

Bookmarks Related papers MentionsView impact

Research paper thumbnail of In vitro propagation and preliminary results of Agrobacterium-mediated genetic transformation of Cordyline fruticosa

South African Journal of Botany, 2015

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Indirect shoot organogenesis and plantlets regeneration from stem of ornamental Dieffenbachia maculata cv. Marianna

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Flowering of Euphorbia millii Plantlets In Vitro as Affected by Paclobutrazol, Light Emitting Diodes (LEDs) and Sucrose

Acta Horticulturae, 2007

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Nutrient utilization during in vitro flowering of Spathiphyllum (Poster presentation)

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Biochemical and Physiological Aspects of Hyperhydricity in Liquid Culture System

ABSTRACT Large-scale liquid cultures and automation have proven the potential to resolve manual h... more ABSTRACT Large-scale liquid cultures and automation have proven the potential to resolve manual handling of in vitro cultures at various stages and decreases production cost. However, hyperhydricity is a major problem during in vitro culture of many crops in liquid culture systems. The environment inside culture vessel normally used in plant micropropagation is characterized by high humidity, limited gaseous exchange between the internal atmosphere of the culture vessel and its surrounding environment, and the accumulation of ethylene, conditions that may induce physiological disorders. Hyperhydricity is a disorder of tissue-cultured plants where leaves become translucent and stems swollen, distorted and brittle. Although numerous hypotheses have been put forward to explain hyperhydricity but there is still a lack of knowledge about the nature of signals responsible for hyperhydricity and the metabolic processes which are affected by its development. The concept of stress in relation to hyperhydricity is not completely established. Therefore, it remains difficult to assume that hyperhydric tissues are stressed. Previous studies argued that abnormal morphology observed in hyperhydricity could be attributed to changes occurring at cellular level due to the modifications of membrane composition or DNA content. In order to understand stress and morphological responses in hyperhydric tissues, in the present article, we are reviewing different biochemical and physiological mechanisms of hyperhydricity in several plant species.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Indirect shoot organogenesis and plantlets regeneration from stem of ornamental Dieffenbachia maculata cv. Marianna

Acta Biologica Szegediensis, 2007

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Effect of Light-Emitting Diode on Growth and Shoot Proliferation of Euphorbia millii and Spathiphyllum cannifolium

Horticulture Environment and Biotechnology, 2005

Bookmarks Related papers MentionsView impact

Research paper thumbnail of 埃及古代农业的历史

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Physiological responses of suspension-cultured Carnation cells to gamma rays irradiation and high temperature stress 辐射和高温胁迫康乃馨悬浮培养细胞生长的影响

RefDoc Bienvenue - Welcome. Refdoc est un service / is powered by. ...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Flowering of Euphorbia Millii Plantlets in Vitro as Affected by Paclobutrazol, Light Emitting Diodes (Leds) and Sucrose

Acta Horticulturae, 2007

Bookmarks Related papers MentionsView impact

Research paper thumbnail of In Vitro Flowering of Spathiphyllum Cannifolium: Influences of Gibberellic Acid, Culture Type and Sucrose Concentration

Acta Horticulturae, 2006

ABSTRACT

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Factors affecting ex vitro rooting and growth of Spathiphyllum plantlets in the microponic culture system

Wonye kwahak kisulchi = Korean journal of horticultural science and technology /

Bookmarks Related papers MentionsView impact

Research paper thumbnail of In vitro flowering of Sathiphyllum cannifolium: Influences of gibberellic acid, culture type and sucrose concentration

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Ornamental Euphorbia and Spathiphyllum: Application of Bioreactor System and Microponics for Large-scale Production, In vitro Flowering and its Physiology

ABSTRACT

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Hyperhydricity: stress related phenomenon?

Wonye kwahak kisulchi = Korean journal of horticultural science and technology /

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Weight loss and antioxidants degradation in spears of five asparagus cultivars during cold and freeze storage

Australian Journal of Crop Science

Asparagus (Asparagus officinalis L) is considered as a vegetable rich in antioxidants. The presen... more Asparagus (Asparagus officinalis L) is considered as a vegetable rich in antioxidants. The present study investigated and compared the weight loss and degradation of antioxidants including ascorbic acid (ASC), glutathione (GSH) and cysteine (CYS) in spears of five asparagus cultivars (Bonlim, Eposs, Mars, Thielim and Vulkan). Spears were stored either under cold storage at 4 °C for 12 days or were deep frozen at - 20 °C for 12 months. The results showed that there are significant differences among asparagus cultivars with respect to their weight loss and antioxidants content of ASC, GSH and CYS. Weight loss and degradation of antioxidants were increased with increasing storage duration. At the end of 12 days period of cold storage, the cultivar Eposs showed the highest weight loss with 3.14%, while for the cultivar Vulkan, the lowest weight loss with 2.14% was recorded. When spears were deep frozen, the weight loss was lower than that recorded under cold storage. After 6 months of s...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of The control of in vitro flowering and association of glutathione metabolism

Floral transition is a complex biological event in the life cycle of flowering plants. In vitro c... more Floral transition is a complex biological event in the life cycle of flowering plants. In vitro culture techniques have important applications towards understanding the flowering process. A single parameter can be investigated to assess its effect on flowering. Investigations on this nature have focused upon the manipulation of media components and culture conditions. Approximately eight decades of in vitro flowering research has been conducted, however, it is difficult to predict how and when flower is to be initiated. This chapter describes various factors controlling in vitro flowering with emphasis on recent findings. The reviewed studies show that in vitro flowering can provide a model system for studying the “switch-on” flowering mechanism and provide means for conducting in vitro breeding. In addition, other applications include; production of early flowering pot plants for commercial market as well as test tube bouquets. The focus of this chapter highlights the relationship ...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Hyperhydricity in African violet (Saintpaulia ionantha H. Wendl) – biochemical aspects of normal versus hyperhydric shoots regenerated via direct adventitious shoots formation

PROPAGATION OF ORNAMENTAL PLANTS

African violet (Saintpaulia ionantha H. Wendl) is one of the most easily and commonly tissue-cult... more African violet (Saintpaulia ionantha H. Wendl) is one of the most easily and commonly tissue-cultured ornamental plants. Despite this, there are limited reports on the direct adventitious shoots from any organ, most papers reporting on an indirect route through callus. In this study, adventitious shoots were induced directly from leaf and petiole explants from in vitro plantlets derived from shoot tip culture. Murashige and Skoog (MS) medium supplemented with 0.2 mg l-1 6-benzyladenine and 0.1 mg l-1 kinetin resulted in 91.65% direct shoot formation from leaf explants and 70% from petiole explants while 32.5 and 17.5 shoots formed per leaf and petiole explant, respectively. The origin of shoots was histologically demonstrated. The potential role of antioxidant enzymes in protecting hyperhydric plantlets from oxidative injury was examined by analyzing antioxidant enzyme activities of hyperhydric and normal tissues. Activities of catalase (CAT), peroxidase (POD), polyphenol oxidase (P...

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Biochemical and Physiological Aspects of Hyperhydricity in Liquid Culture System

Production of Biomass and Bioactive Compounds Using Bioreactor Technology, 2014

ABSTRACT Large-scale liquid cultures and automation have proven the potential to resolve manual h... more ABSTRACT Large-scale liquid cultures and automation have proven the potential to resolve manual handling of in vitro cultures at various stages and decreases production cost. However, hyperhydricity is a major problem during in vitro culture of many crops in liquid culture systems. The environment inside culture vessel normally used in plant micropropagation is characterized by high humidity, limited gaseous exchange between the internal atmosphere of the culture vessel and its surrounding environment, and the accumulation of ethylene, conditions that may induce physiological disorders. Hyperhydricity is a disorder of tissue-cultured plants where leaves become translucent and stems swollen, distorted and brittle. Although numerous hypotheses have been put forward to explain hyperhydricity but there is still a lack of knowledge about the nature of signals responsible for hyperhydricity and the metabolic processes which are affected by its development. The concept of stress in relation to hyperhydricity is not completely established. Therefore, it remains difficult to assume that hyperhydric tissues are stressed. Previous studies argued that abnormal morphology observed in hyperhydricity could be attributed to changes occurring at cellular level due to the modifications of membrane composition or DNA content. In order to understand stress and morphological responses in hyperhydric tissues, in the present article, we are reviewing different biochemical and physiological mechanisms of hyperhydricity in several plant species.

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Influences of explant type and enzyme incubation on isolated protoplast density and viability in two garlic cultivars

Bookmarks Related papers MentionsView impact

Research paper thumbnail of In vitro propagation and preliminary results of Agrobacterium-mediated genetic transformation of Cordyline fruticosa

South African Journal of Botany, 2015

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Indirect shoot organogenesis and plantlets regeneration from stem of ornamental Dieffenbachia maculata cv. Marianna

Bookmarks Related papers MentionsView impact