Thidiazuron induced somatic embryogenesis in Coffea arabica L. and Coffea canephora P ex Fr.

The rapid direct and repetitive somatic embryogenesis in Coffea arabica and C. canephora genotypes was tested on Murashige and Skoog medium (MS) containing thidiazuron (TDZ) (1-phenyl-3-(1,2,3,-thiadiazol-5-yl)urea) in concentrations of 2.27–11.35s M. Segments taken from cotyledon leaf, first leaf and stalk of regenerated plantlets produced clusters of somatic embryos directly from cut portions of explants on TDZ (9.08 M) containing medium within a period of two months. Subculturing of these embryo clusters produced more secondary embryos on reduced TDZ (0.045–0.91M) containing medium and these subsequently developed into plantlets (80–85%) on development medium followed by rooting on MS basal medium. This direct somatic embryogenesis from leaf and hypocotyl explants in Coffea sp. is a strong evidence of cell totipotency. The rapid somatic embryo induction protocol would be useful for the mass propagation, direct regeneration and genetic transformation of selected elite lines

AgNO3 - a potential regulator of ethylene activity and plant growth modulator

The aim of this review is to critically analyze the role of silver nitrate (AgNO3) in modulating plant growth and development. In recent years, basic studies on ethylene regulation opened new vistas for applied research in the area of micro-propagation, somatic embryogenesis, in vitro flowering, growth promotion, fruit ripening, and sex expression. Silver nitrate has proved to be a very potent inhibitor of ethylene action and is widely used in plant tissue culture. Few properties of silver nitrate such as easy availability, solubility in water, specificity and stability make it very useful for various applications in exploiting plant growth regulation and morphogenesis in vivo and in vitro. Silver ion mediated responses seem to be involved in polyamines, ethyleneand calcium- mediated pathways, and play a crucial role in regulating physiological process including morphogenesis. The molecular basis for regulation of morphogenesis under the influence of silver nitrate is completely lacking. This review compiles published reports of silver nitrate-mediated in vitro and in vivo studies and focuses on fundamental and applied aspects of plant growth modulation under the influence of silver nitrate

Induction of in vitro flowering in Capsicum frutescens under the influence of silver nitrate and cobalt chloride and pollen transformation

The influence of silver nitrate (AgNO3) and cobalt chloride (CoCl2) on shoot multiplication and in vitro flowering in Capsicum frutescens Mill. was investigated. Exogenous administration of AgNO3 and CoCl2 at a concentration of 30 \ub5M resulted in the maximum tissue response in terms of shoot length and number of shoots after 45 days culturing on MS medium. Both silver nitrate (40 \ub5M) and cobalt chloride (30 \ub5M) influenced in vitro flowering after 25 and 45 days respectively. This is the first report on in vitro flowering in C. frutescens. The study also demonstrated successful transformation of pollen obtained from the in vitro flowers. Since capsicum is highly recalcitrant to in vitro plant regeneration, the results of the study may be highly useful in transformation of capsicum using germ free in vitro flowers

AgNO3 - a potential regulator of ethylene activity and plant growth modulator

The aim of this review is to critically analyze the role of silver nitrate (AgNO3) in modulating plant growth and development. In recent years, basic studies on ethylene regulation opened new vistas for applied research in the area of micro-propagation, somatic embryogenesis, in vitro flowering, growth promotion, fruit ripening, and sex expression. Silver nitrate has proved to be a very potent inhibitor of ethylene action and is widely used in plant tissue culture. Few properties of silver nitrate such as easy availability, solubility in water, specificity and stability make it very useful for various applications in exploiting plant growth regulation and morphogenesis in vivo and in vitro. Silver ion mediated responses seem to be involved in polyamines, ethyleneand calcium- mediated pathways, and play a crucial role in regulating physiological process including morphogenesis. The molecular basis for regulation of morphogenesis under the influence of silver nitrate is completely lacking. This review compiles published reports of silver nitrate-mediated in vitro and in vivo studies and focuses on fundamental and applied aspects of plant growth modulation under the influence of silver nitrate

Induction of in vitro flowering in Capsicum frutescens under the influence of silver nitrate and cobalt chloride and pollen transformation

The influence of silver nitrate (AgNO3) and cobalt chloride (CoCl2) on shoot multiplication and in vitro flowering in Capsicum frutescens Mill. was investigated. Exogenous administration of AgNO3 and CoCl2 at a concentration of 30 µM resulted in the maximum tissue response in terms of shoot length and number of shoots after 45 days culturing on MS medium. Both silver nitrate (40 µM) and cobalt chloride (30 µM) influenced in vitro flowering after 25 and 45 days respectively. This is the first report on in vitro flowering in C. frutescens. The study also demonstrated successful transformation of pollen obtained from the in vitro flowers. Since capsicum is highly recalcitrant to in vitro plant regeneration, the results of the study may be highly useful in transformation of capsicum using germ free in vitro flowers

Thidiazuron induced somatic embryogenesis in Coffea arabica L. and Coffea canephora P ex Fr.

The rapid direct and repetitive somatic embryogenesis in Coffea arabica and C. canephora genotypes was tested on Murashige and Skoog medium (MS) containing thidiazuron (TDZ) (1-phenyl-3-(1,2,3,-thiadiazol-5-yl)urea) in concentrations of 2.27–11.35s M. Segments taken from cotyledon leaf, first leaf and stalk of regenerated plantlets produced clusters of somatic embryos directly from cut portions of explants on TDZ (9.08 M) containing medium within a period of two months. Subculturing of these embryo clusters produced more secondary embryos on reduced TDZ (0.045–0.91M) containing medium and these subsequently developed into plantlets (80–85%) on development medium followed by rooting on MS basal medium. This direct somatic embryogenesis from leaf and hypocotyl explants in Coffea sp. is a strong evidence of cell totipotency. The rapid somatic embryo induction protocol would be useful for the mass propagation, direct regeneration and genetic transformation of selected elite lines

Variation in in vitro Morphogenic Response to Growth Regulators in Soybean Genotypes from India and Bulgaria

Soybean (Glycinae max (L.) Merrill.) is receiving great global importance due to its nutraceutical value but its cultivation suffers the problems of biotic/abiotic stress. To improve soybean germplasm biotechnological approach can be applied. The objectives of the experiments were to study the possibilities for establishment of in vitro cultures which can be used for genetic manipulations and modelling of stress. In vitro morphogeneic response of two Indian (Hardee and JS 335), one Bulgarian (Daniela) and one american (Hodson) soybean cultivars were studied using plant growth regulators. Using cotyledonary nodes as explants, high organogenic response was observed for cv Daniela and cv Hodson on media containig BAP and IBA. TDZ induced multiple shoot buds in all the cultivars, with varying degree of response and it was found to be genotype specific. A maximum of 8 shoot buds were obtained from cotyledonary node explants in presence of TDZ (0.5 mg/l) for the cv. Hardee. A negative correlation was observed between bud number and size for the Bulgarian cultivars. The results indicate the stimulating effect of TDZ on organogenesis and the interaction of genotype and culture media, which can be utilized for crop improvement using tissue culture techniques