The Experts below are selected from a list of 81 Experts worldwide ranked by ideXlab platform
Claudio Stasolla - One of the best experts on this subject based on the ideXlab platform.
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improved development of microspore Derived Embryo cultures of brassica napus cv topaz following changes in glutathione metabolism
Physiologia Plantarum, 2006Co-Authors: Mark F Belmonte, Stephen J Ambrose, Andrew R S Ross, Suzanne R Abrams, Claudio StasollaAbstract:Glutathione has been shown to play an important role during Embryo development in both plant and animal systems. The effects of altered glutathione metabolism during microspore-Derived Embryos (MDEs) of Brassica napus were investigated following exogenous application of reduced glutathione (GSH), its oxidized form (GSSG) and buthionine sulfoximine (BSO), an inhibitor of glutathione de novo synthesis. Applications of BSO which lowered the cellular glutathione redox status, i.e. GSH/(GSH + GSSG), enhanced significantly the quality of the Embryos and their ability to convert into viable plants. Histological analyses revealed that inclusions of BSO in the culture medium altered the pattern of storage product accumulation in the Embryos and improved the architecture of the shoot apical meristems (SAMs). Compared with their control counterparts which showed severe signs of SAM deterioration, such as the formation of intercellular spaces and differentiation of the meristematic cells, BSO-treated Embryos had well-organized SAMs. The improved SAM organization observed in the presence of BSO also correlated with the proper localization pattern of WUSCHEL, a SAM molecular marker gene which was miss-expressed in control Embryos. The beneficial effects of BSO on Embryo development and conversion were ascribed to the increasing levels of ABA. The concentration of this growth regulator in BSO-treated Embryos was always higher than that of control Embryos during the second half of the maturation period. Furthermore, many structural alterations induced by BSO could be reproduced in Embryos cultured in the presence of ABA. Taken together, these results suggest that a lowering of the glutathione redox status during Embryo development may represent a metabolic switch needed for increasing the endogenous levels of ABA, which is required for successful completion of the developmental program.
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Improved development of microspore‐Derived Embryo cultures of Brassica napus cv Topaz following changes in glutathione metabolism
Physiologia Plantarum, 2006Co-Authors: Mark F Belmonte, Stephen J Ambrose, Andrew R S Ross, Suzanne R Abrams, Claudio StasollaAbstract:Glutathione has been shown to play an important role during Embryo development in both plant and animal systems. The effects of altered glutathione metabolism during microspore-Derived Embryos (MDEs) of Brassica napus were investigated following exogenous application of reduced glutathione (GSH), its oxidized form (GSSG) and buthionine sulfoximine (BSO), an inhibitor of glutathione de novo synthesis. Applications of BSO which lowered the cellular glutathione redox status, i.e. GSH/(GSH + GSSG), enhanced significantly the quality of the Embryos and their ability to convert into viable plants. Histological analyses revealed that inclusions of BSO in the culture medium altered the pattern of storage product accumulation in the Embryos and improved the architecture of the shoot apical meristems (SAMs). Compared with their control counterparts which showed severe signs of SAM deterioration, such as the formation of intercellular spaces and differentiation of the meristematic cells, BSO-treated Embryos had well-organized SAMs. The improved SAM organization observed in the presence of BSO also correlated with the proper localization pattern of WUSCHEL, a SAM molecular marker gene which was miss-expressed in control Embryos. The beneficial effects of BSO on Embryo development and conversion were ascribed to the increasing levels of ABA. The concentration of this growth regulator in BSO-treated Embryos was always higher than that of control Embryos during the second half of the maturation period. Furthermore, many structural alterations induced by BSO could be reproduced in Embryos cultured in the presence of ABA. Taken together, these results suggest that a lowering of the glutathione redox status during Embryo development may represent a metabolic switch needed for increasing the endogenous levels of ABA, which is required for successful completion of the developmental program.
Haeyoung Na - One of the best experts on this subject based on the ideXlab platform.
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Microspore-Derived Embryo Formation and Morphological Changes during the Isolated Microspore Culture of Radish (Raphanus sativus L.)
Korean Journal of Horticultural Science & Technology, 2014Co-Authors: Han Young Park, Haeyoung NaAbstract:Raphanus sativus L. cv. Taebaek, a efficiently microspore-Derived Embryo (MDE)-forming cultivar, and ‘Chungwoon’, a non-MDE-forming cultivar were selected as donor plants for isolated microspore culture. Radish flower bud of 2.0 (small, S), 4.0 (medium, M), and 6.0 (large, L) ± 0.5 ㎜ in length were isolated to determine the temporal relationship between flower bud size and MED yield. Anatomical observations revealed no difference in the structure of the flower buds between the two cultivars. In both cultivars, the stigmas were much longer than the floral leaf in M-sized flower buds. The MDE yields for ‘Taebaek’ per petri dish were 6.6 and 1.3 for M- and L-sized of flower buds, respectively, but MDE formation was not induced in the S flower buds. On the other hand, ‘Chungwoon’ failed to form MDEs in all flower buds. The microspore density of ‘Taebaek’ was 1.3 times more than that of ‘Chungwoon’ for M sized flower buds. Of the M-sized buds from ‘Taebaek’ and ‘Chungwoon’, 92.1 and 81.6%, respectively, were in the late uninucleate microspore stage, which is characterized by the highest frequency of MDE formation. Anatomical observations of MDE formation revealed that the microspores were able to divide to form a primordium from which cell division took place continuously in the ‘Teabeak’ cultivar. However, the microspores of ‘Chungwoon’ failed to progress beyond the primodium stage, resulting in lack of MDE formation. By contrast, after the formation of the primordium, various developmental stages of embyos from microspore were observed in the ‘Taebaek’ cultivar. These results can be used to determine MDE forming potentials of radish cultivars.
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Microspore-Derived Embryo formation in radish (Raphanus sativus L.) according to nutritional and environmental conditions
Horticulture Environment and Biotechnology, 2011Co-Authors: Changhoo Chun, Hanyong Park, Haeyoung NaAbstract:Composition of nutrient media, flower bud size, sucrose concentration, heat shock stress, and ethylene inhibitor could have marked effects on microspore Embryogenesis. No microspore-Derived Embryos (MDE) were formed when the microspores were isolated from radish (Raphanus sativus L.) flower buds of 1.0–2.5 mm in size, whereas MDE were formed with microspores isolated from 2.5–4.5 and 4.5–6.5 mm flower buds. The microspores isolated from 2.5–4.5 mm flower buds showed high Embryo yields. MDE formation was highest when 150 g·L−1 sucrose was added to the half strength Nitsch & Nitsch (NLN) liquid medium, but at sucrose concentrations less than 100 g·L−1 there was no MDE formation. Microspores cultured on half strength NLN liquid medium containing 0.05 mg·L−1 silver nitrate (AgNO3) produced the most MDE, showing more than two-fold increase in yield compared to those cultured on medium without AgNO3. A heat shock pretreatment of microspores at 32°C for 24 h gave high-frequency production of MDE when compare to higher or lower temperatures; no MDE were formed at 42.5°C. The highest yield of MDE was observed when microspores were Derived from 2.5–4.5 mm flower buds cultured on half strength NLN medium containing 150 g·L −1 sucrose, 0.05 mg·L−1 AgNO3, and precultured with heat shock pretreatment of microspores at 32°C for 24 h, followed by incubation 25°C for 30 days. A polyploidy test indicated that 19.7% of the microspore-Derived plants were doubled haploid, other plants were haploid, and chimeras were haploid and diploid.
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the effects of plant growth regulators activated charcoal and agno3 on microspore Derived Embryo formation in broccoli brassica oleracea l var italica
Horticulture Environment and Biotechnology, 2011Co-Authors: Haeyoung Na, Jungho Kwak, Changhoo ChunAbstract:Embryos Derived from isolated microspore culture are of great importance for producing homozygous plants for breeding. Microspore culture can reduce time and laborious effort in the breeding of Brassica plants. Microspore Derived Embryos (MDE) formation in broccoli (Brassica oleracea L. var. italica Plenck) was studied with different plant growth regulators (PGRs), activated charcoal, and silver nitrate (AgNO3) to determine the optimal chemical conditions in the microspore culture. A 6-benzylaminopurine (BA) concentration of 0.05 mg L−1 resulted in increased MDE formation compared to those at other BA concentrations. Compared to the 0.05 mg L−1 BA concentration, fewer MDEs were formed in BA concentrations exceeding 0.1 mg L−1, similar to those cultured on medium without BA. However, 0.5× Nitsch & Nitsch (NLN) liquid medium supplemented with 0.05 mg L−1 napthalene acetic acid (NAA) and BA was more effective in inducing MDE formation than was BA alone. The higher MDE formation rate was observed in 0.5× NLN liquid culture medium containing 0.05 mg L−1 NAA and 0.01 mg L−1 BA. The MDE yield was significantly higher in all concentrations when activated charcoal was added to the microspore culture media. The optimal concentration of activated charcoal was 1.0 mg per petri dish, and the optimum AgNO3 concentration was 0.1 mg L−1, which induced MDE formation to 26.2 Embryos, compared to 11.6 Embryos without AgNO3.
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Microspore Derived Embryo formation and doubled haploid plant production in broccoli ( Brassica oleracea L. var italica ) according to nutritional and environmental conditions
African Journal of Biotechnology, 2011Co-Authors: Haeyoung Na, Jungho Kwak, Gui-young Hwang, Moo Koung Yoon, Changhoo ChunAbstract:In cell culture, the maintenance of proper growing conditions is a key approach for improving the formation of Embryos, and is useful in the production of doubled haploid (DH) plants. Optimal nutritional and environmental conditions for the microspore culture of Brassica oleracea L. var italica were determined in order to reduce time and effort in breeding. The optimal conditions for microspore Embryo formation differed depending on genotype. Microspore-Derived Embryos (MDE) formation was influenced by the strength of the NLN medium, the microelement and sugar concentration, and the heat shock temperature and period. The 0.5XNLN liquid medium was the most favorable for MDE formation. The most efficient formation of MDE was observed in the 0.5X NLN liquid medium, without the addition of microelements. When 13 or 15% sucrose was added to the 0.5X NLN liquid medium, the amount of normal MDE formation increased. The optimum heat shock temperature and period for MDE formation was 32.5°C and 24 h, respectively. A polyploidy test indicated that 30% of the microspore Derived plants were diploid throughout the Embryogenesis process.
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Microspore-Derived Embryo Formation in Response to Cold Pretreatment, Washing Medium, and Medium Composition of Radish (Raphanus sativus L.)
Korean Journal of Horticultural Science & Technology, 2011Co-Authors: Changhoo Chun, Haeyoung NaAbstract:Cold pretreatment, washing medium and composition of nutrient media may have marked effects on microspore Embryogenesis. When microspores isolated from radish (Raphanus sativus L. cv. Gwanhun) flower buds were washed with Nitsch & Nitsch (NLN) medium liquid medium containing 130 g?L -1 sucrose (NLN-13), yields of microspore-Derived Embryos were greater than when using B5 liquid medium containing 130 g?L -1 sucrose. Microspore viability is known to decrease rapidly with storage; however, in this experiment, microspore viability was maintained for 24 h at 4°C without media. Among the various medium concentrations used (0.25×, 0.5×, 1.0×, 2.0×, and 4.0× NLN liquid medium), 0.5× NLN liquid medium induced the most efficient formation of microspore-Derived Embryos. In addition, microspore-Derived Embryos yields were greater when microspores were cultured in 0.5× NLN liquid medium supplemented with 0.25×, 0.5×, and 1.0× NLN microelements, compared to medium not supplemented with microelements. In this study, the highest yield of microspore-Derived Embryos was observed when the microspores Derived from flower buds were washed using NLN-13 liquid medium and then cultured on 0.5× NLN liquid medium supplemented with 0.25× NLN microelements, followed by incubation at 25°C for 30 days.
Mark F Belmonte - One of the best experts on this subject based on the ideXlab platform.
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improved development of microspore Derived Embryo cultures of brassica napus cv topaz following changes in glutathione metabolism
Physiologia Plantarum, 2006Co-Authors: Mark F Belmonte, Stephen J Ambrose, Andrew R S Ross, Suzanne R Abrams, Claudio StasollaAbstract:Glutathione has been shown to play an important role during Embryo development in both plant and animal systems. The effects of altered glutathione metabolism during microspore-Derived Embryos (MDEs) of Brassica napus were investigated following exogenous application of reduced glutathione (GSH), its oxidized form (GSSG) and buthionine sulfoximine (BSO), an inhibitor of glutathione de novo synthesis. Applications of BSO which lowered the cellular glutathione redox status, i.e. GSH/(GSH + GSSG), enhanced significantly the quality of the Embryos and their ability to convert into viable plants. Histological analyses revealed that inclusions of BSO in the culture medium altered the pattern of storage product accumulation in the Embryos and improved the architecture of the shoot apical meristems (SAMs). Compared with their control counterparts which showed severe signs of SAM deterioration, such as the formation of intercellular spaces and differentiation of the meristematic cells, BSO-treated Embryos had well-organized SAMs. The improved SAM organization observed in the presence of BSO also correlated with the proper localization pattern of WUSCHEL, a SAM molecular marker gene which was miss-expressed in control Embryos. The beneficial effects of BSO on Embryo development and conversion were ascribed to the increasing levels of ABA. The concentration of this growth regulator in BSO-treated Embryos was always higher than that of control Embryos during the second half of the maturation period. Furthermore, many structural alterations induced by BSO could be reproduced in Embryos cultured in the presence of ABA. Taken together, these results suggest that a lowering of the glutathione redox status during Embryo development may represent a metabolic switch needed for increasing the endogenous levels of ABA, which is required for successful completion of the developmental program.
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Improved development of microspore‐Derived Embryo cultures of Brassica napus cv Topaz following changes in glutathione metabolism
Physiologia Plantarum, 2006Co-Authors: Mark F Belmonte, Stephen J Ambrose, Andrew R S Ross, Suzanne R Abrams, Claudio StasollaAbstract:Glutathione has been shown to play an important role during Embryo development in both plant and animal systems. The effects of altered glutathione metabolism during microspore-Derived Embryos (MDEs) of Brassica napus were investigated following exogenous application of reduced glutathione (GSH), its oxidized form (GSSG) and buthionine sulfoximine (BSO), an inhibitor of glutathione de novo synthesis. Applications of BSO which lowered the cellular glutathione redox status, i.e. GSH/(GSH + GSSG), enhanced significantly the quality of the Embryos and their ability to convert into viable plants. Histological analyses revealed that inclusions of BSO in the culture medium altered the pattern of storage product accumulation in the Embryos and improved the architecture of the shoot apical meristems (SAMs). Compared with their control counterparts which showed severe signs of SAM deterioration, such as the formation of intercellular spaces and differentiation of the meristematic cells, BSO-treated Embryos had well-organized SAMs. The improved SAM organization observed in the presence of BSO also correlated with the proper localization pattern of WUSCHEL, a SAM molecular marker gene which was miss-expressed in control Embryos. The beneficial effects of BSO on Embryo development and conversion were ascribed to the increasing levels of ABA. The concentration of this growth regulator in BSO-treated Embryos was always higher than that of control Embryos during the second half of the maturation period. Furthermore, many structural alterations induced by BSO could be reproduced in Embryos cultured in the presence of ABA. Taken together, these results suggest that a lowering of the glutathione redox status during Embryo development may represent a metabolic switch needed for increasing the endogenous levels of ABA, which is required for successful completion of the developmental program.
Changhoo Chun - One of the best experts on this subject based on the ideXlab platform.
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Microspore-Derived Embryo formation in radish (Raphanus sativus L.) according to nutritional and environmental conditions
Horticulture Environment and Biotechnology, 2011Co-Authors: Changhoo Chun, Hanyong Park, Haeyoung NaAbstract:Composition of nutrient media, flower bud size, sucrose concentration, heat shock stress, and ethylene inhibitor could have marked effects on microspore Embryogenesis. No microspore-Derived Embryos (MDE) were formed when the microspores were isolated from radish (Raphanus sativus L.) flower buds of 1.0–2.5 mm in size, whereas MDE were formed with microspores isolated from 2.5–4.5 and 4.5–6.5 mm flower buds. The microspores isolated from 2.5–4.5 mm flower buds showed high Embryo yields. MDE formation was highest when 150 g·L−1 sucrose was added to the half strength Nitsch & Nitsch (NLN) liquid medium, but at sucrose concentrations less than 100 g·L−1 there was no MDE formation. Microspores cultured on half strength NLN liquid medium containing 0.05 mg·L−1 silver nitrate (AgNO3) produced the most MDE, showing more than two-fold increase in yield compared to those cultured on medium without AgNO3. A heat shock pretreatment of microspores at 32°C for 24 h gave high-frequency production of MDE when compare to higher or lower temperatures; no MDE were formed at 42.5°C. The highest yield of MDE was observed when microspores were Derived from 2.5–4.5 mm flower buds cultured on half strength NLN medium containing 150 g·L −1 sucrose, 0.05 mg·L−1 AgNO3, and precultured with heat shock pretreatment of microspores at 32°C for 24 h, followed by incubation 25°C for 30 days. A polyploidy test indicated that 19.7% of the microspore-Derived plants were doubled haploid, other plants were haploid, and chimeras were haploid and diploid.
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the effects of plant growth regulators activated charcoal and agno3 on microspore Derived Embryo formation in broccoli brassica oleracea l var italica
Horticulture Environment and Biotechnology, 2011Co-Authors: Haeyoung Na, Jungho Kwak, Changhoo ChunAbstract:Embryos Derived from isolated microspore culture are of great importance for producing homozygous plants for breeding. Microspore culture can reduce time and laborious effort in the breeding of Brassica plants. Microspore Derived Embryos (MDE) formation in broccoli (Brassica oleracea L. var. italica Plenck) was studied with different plant growth regulators (PGRs), activated charcoal, and silver nitrate (AgNO3) to determine the optimal chemical conditions in the microspore culture. A 6-benzylaminopurine (BA) concentration of 0.05 mg L−1 resulted in increased MDE formation compared to those at other BA concentrations. Compared to the 0.05 mg L−1 BA concentration, fewer MDEs were formed in BA concentrations exceeding 0.1 mg L−1, similar to those cultured on medium without BA. However, 0.5× Nitsch & Nitsch (NLN) liquid medium supplemented with 0.05 mg L−1 napthalene acetic acid (NAA) and BA was more effective in inducing MDE formation than was BA alone. The higher MDE formation rate was observed in 0.5× NLN liquid culture medium containing 0.05 mg L−1 NAA and 0.01 mg L−1 BA. The MDE yield was significantly higher in all concentrations when activated charcoal was added to the microspore culture media. The optimal concentration of activated charcoal was 1.0 mg per petri dish, and the optimum AgNO3 concentration was 0.1 mg L−1, which induced MDE formation to 26.2 Embryos, compared to 11.6 Embryos without AgNO3.
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Microspore Derived Embryo formation and doubled haploid plant production in broccoli ( Brassica oleracea L. var italica ) according to nutritional and environmental conditions
African Journal of Biotechnology, 2011Co-Authors: Haeyoung Na, Jungho Kwak, Gui-young Hwang, Moo Koung Yoon, Changhoo ChunAbstract:In cell culture, the maintenance of proper growing conditions is a key approach for improving the formation of Embryos, and is useful in the production of doubled haploid (DH) plants. Optimal nutritional and environmental conditions for the microspore culture of Brassica oleracea L. var italica were determined in order to reduce time and effort in breeding. The optimal conditions for microspore Embryo formation differed depending on genotype. Microspore-Derived Embryos (MDE) formation was influenced by the strength of the NLN medium, the microelement and sugar concentration, and the heat shock temperature and period. The 0.5XNLN liquid medium was the most favorable for MDE formation. The most efficient formation of MDE was observed in the 0.5X NLN liquid medium, without the addition of microelements. When 13 or 15% sucrose was added to the 0.5X NLN liquid medium, the amount of normal MDE formation increased. The optimum heat shock temperature and period for MDE formation was 32.5°C and 24 h, respectively. A polyploidy test indicated that 30% of the microspore Derived plants were diploid throughout the Embryogenesis process.
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Microspore-Derived Embryo Formation in Response to Cold Pretreatment, Washing Medium, and Medium Composition of Radish (Raphanus sativus L.)
Korean Journal of Horticultural Science & Technology, 2011Co-Authors: Changhoo Chun, Haeyoung NaAbstract:Cold pretreatment, washing medium and composition of nutrient media may have marked effects on microspore Embryogenesis. When microspores isolated from radish (Raphanus sativus L. cv. Gwanhun) flower buds were washed with Nitsch & Nitsch (NLN) medium liquid medium containing 130 g?L -1 sucrose (NLN-13), yields of microspore-Derived Embryos were greater than when using B5 liquid medium containing 130 g?L -1 sucrose. Microspore viability is known to decrease rapidly with storage; however, in this experiment, microspore viability was maintained for 24 h at 4°C without media. Among the various medium concentrations used (0.25×, 0.5×, 1.0×, 2.0×, and 4.0× NLN liquid medium), 0.5× NLN liquid medium induced the most efficient formation of microspore-Derived Embryos. In addition, microspore-Derived Embryos yields were greater when microspores were cultured in 0.5× NLN liquid medium supplemented with 0.25×, 0.5×, and 1.0× NLN microelements, compared to medium not supplemented with microelements. In this study, the highest yield of microspore-Derived Embryos was observed when the microspores Derived from flower buds were washed using NLN-13 liquid medium and then cultured on 0.5× NLN liquid medium supplemented with 0.25× NLN microelements, followed by incubation at 25°C for 30 days.
Andrew R S Ross - One of the best experts on this subject based on the ideXlab platform.
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improved development of microspore Derived Embryo cultures of brassica napus cv topaz following changes in glutathione metabolism
Physiologia Plantarum, 2006Co-Authors: Mark F Belmonte, Stephen J Ambrose, Andrew R S Ross, Suzanne R Abrams, Claudio StasollaAbstract:Glutathione has been shown to play an important role during Embryo development in both plant and animal systems. The effects of altered glutathione metabolism during microspore-Derived Embryos (MDEs) of Brassica napus were investigated following exogenous application of reduced glutathione (GSH), its oxidized form (GSSG) and buthionine sulfoximine (BSO), an inhibitor of glutathione de novo synthesis. Applications of BSO which lowered the cellular glutathione redox status, i.e. GSH/(GSH + GSSG), enhanced significantly the quality of the Embryos and their ability to convert into viable plants. Histological analyses revealed that inclusions of BSO in the culture medium altered the pattern of storage product accumulation in the Embryos and improved the architecture of the shoot apical meristems (SAMs). Compared with their control counterparts which showed severe signs of SAM deterioration, such as the formation of intercellular spaces and differentiation of the meristematic cells, BSO-treated Embryos had well-organized SAMs. The improved SAM organization observed in the presence of BSO also correlated with the proper localization pattern of WUSCHEL, a SAM molecular marker gene which was miss-expressed in control Embryos. The beneficial effects of BSO on Embryo development and conversion were ascribed to the increasing levels of ABA. The concentration of this growth regulator in BSO-treated Embryos was always higher than that of control Embryos during the second half of the maturation period. Furthermore, many structural alterations induced by BSO could be reproduced in Embryos cultured in the presence of ABA. Taken together, these results suggest that a lowering of the glutathione redox status during Embryo development may represent a metabolic switch needed for increasing the endogenous levels of ABA, which is required for successful completion of the developmental program.
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Improved development of microspore‐Derived Embryo cultures of Brassica napus cv Topaz following changes in glutathione metabolism
Physiologia Plantarum, 2006Co-Authors: Mark F Belmonte, Stephen J Ambrose, Andrew R S Ross, Suzanne R Abrams, Claudio StasollaAbstract:Glutathione has been shown to play an important role during Embryo development in both plant and animal systems. The effects of altered glutathione metabolism during microspore-Derived Embryos (MDEs) of Brassica napus were investigated following exogenous application of reduced glutathione (GSH), its oxidized form (GSSG) and buthionine sulfoximine (BSO), an inhibitor of glutathione de novo synthesis. Applications of BSO which lowered the cellular glutathione redox status, i.e. GSH/(GSH + GSSG), enhanced significantly the quality of the Embryos and their ability to convert into viable plants. Histological analyses revealed that inclusions of BSO in the culture medium altered the pattern of storage product accumulation in the Embryos and improved the architecture of the shoot apical meristems (SAMs). Compared with their control counterparts which showed severe signs of SAM deterioration, such as the formation of intercellular spaces and differentiation of the meristematic cells, BSO-treated Embryos had well-organized SAMs. The improved SAM organization observed in the presence of BSO also correlated with the proper localization pattern of WUSCHEL, a SAM molecular marker gene which was miss-expressed in control Embryos. The beneficial effects of BSO on Embryo development and conversion were ascribed to the increasing levels of ABA. The concentration of this growth regulator in BSO-treated Embryos was always higher than that of control Embryos during the second half of the maturation period. Furthermore, many structural alterations induced by BSO could be reproduced in Embryos cultured in the presence of ABA. Taken together, these results suggest that a lowering of the glutathione redox status during Embryo development may represent a metabolic switch needed for increasing the endogenous levels of ABA, which is required for successful completion of the developmental program.