Abstract
Somatic embryogenesis in pumpkin can be induced on auxin-containing medium but also on hormone-free medium containing 1 mM ammonium (NH4+) as the sole source of nitrogen. Growth of ammonium-induced embryogenic tissue was slow and caused considerable acidification of the culture medium. In order to distinguish NH4+ effects from pH effects, the NH4-only medium was buffered with MES but no further differentiation was observed. Proembryogenic cell clusters, consisted of small spherical cells with dense cytoplasma, could develop into late stage embryos only after the re-supply of nitrogen in form of nitrate or L-glutamine. Suboptimal supply of nitrogen starvation led to a marked decline in protein biosynthesis, whereas it induced an increase in the level of lipid peroxidation, as estimated by malondialdehyde (MDA). The activities of antioxidative enzymes superoxide dismutase (SOD) and soluble peroxidase (POD) were high in tissues growing into NH4+ medium, and decreased after re-supply of nitrogen what indicated oxidative stress in the tissue assimilating only NH4+. In addition, ammonium-induced embryogenic tissue was characterized by elevated activity of esterase, the early marker of somatic embryogenesis, what was in accordance with highly proembryogenic state of the culture. Together, results show that the induction and development of embryogenic competence in pumpkin is associated with the oxidative stress as induced by nitrogen limitation.
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Claims 8
Claim · model-written summary
Ammonium alone induced pumpkin somatic embryogenesis on hormone-free medium.
- Taxon
- pumpkine0
- Treatment
- 1 mM ammonium (NH4+)e0
- Outcome
- Somatic embryogenesise0
- Comparator
- auxin-containing mediume0
Not reportedDirection
Verbatim
e0“Somatic embryogenesis in pumpkin can be induced on auxin-containing medium but also on hormone-free medium containing 1 mM ammonium (NH4+) as the sole source of nitrogen”
Claim · model-written summary
Ammonium-induced embryogenic tissue grew slowly and acidified the medium.
Verbatim
e0“Growth of ammonium-induced embryogenic tissue was slow and caused considerable acidification of the culture medium”
t0“PUMPKIN”
Claim · model-written summary
MES buffering of ammonium-only medium produced no further differentiation.
- Taxon
- PUMPKINt0
- Treatment
- buffered with MESe0
- Outcome
- differentiatione0
- Direction
- no further differentiatione0
Not reportedComparator
Verbatim
e0“the NH4-only medium was buffered with MES but no further differentiation was observed”
t0“PUMPKIN”
Claim · model-written summary
Proembryogenic clusters reached late embryo stages only after nitrate or L-glutamine resupply.
- Taxon
- PUMPKINt0
- Organ / stage
- Proembryogenic cell clusterse0
- Treatment
- re-supply of nitrogen in form of nitrate or L-glutaminee0
- Outcome
- develop into late stage embryose0
Not reportedComparatorDirection
Verbatim
e0“Proembryogenic cell clusters, consisted of small spherical cells with dense cytoplasma, could develop into late stage embryos only after the re-supply of nitrogen in form of nitrate or L-glutamine”
t0“PUMPKIN”
Claim · model-written summary
Nitrogen limitation decreased protein biosynthesis.
- Taxon
- PUMPKINt0
- Treatment
- Suboptimal supply of nitrogen starvatione0
- Outcome
- protein biosynthesise0
- Direction
- declinee0
Not reportedComparator
Verbatim
e0“Suboptimal supply of nitrogen starvation led to a marked decline in protein biosynthesis”
t0“PUMPKIN”
Claim · model-written summary
Nitrogen limitation increased lipid peroxidation estimated by MDA.
- Taxon
- PUMPKINt0
- Treatment
- Suboptimal supply of nitrogen starvatione0
- Outcome
- lipid peroxidatione0
- Direction
- increasee0
Not reportedComparator
Verbatim
e0“Suboptimal supply of nitrogen starvation led to a marked decline in protein biosynthesis, whereas it induced an increase in the level of lipid peroxidation, as estimated by malondialdehyde (MDA)”
t0“PUMPKIN”
Claim · model-written summary
SOD and POD activities were high on ammonium medium and decreased after nitrogen resupply.
Verbatim
e0“The activities of antioxidative enzymes superoxide dismutase (SOD) and soluble peroxidase (POD) were high in tissues growing into NH4+ medium, and decreased after re-supply of nitrogen”
t0“PUMPKIN”
Claim · model-written summary
Ammonium-induced embryogenic tissue had elevated esterase activity.
Verbatim
e0“ammonium-induced embryogenic tissue was characterized by elevated activity of esterase, the early marker of somatic embryogenesis”
t0“PUMPKIN”
The same questions in other papers
ammonium · growth · Cucurbita (pumpkins)Results agree
2 papers in the same direction as this paper
- positive
- positive
nitrogen · growth · Cucurbita (pumpkins)Positive and negative results
11 papers in the same direction as this paper · 2 in the opposite direction
- no effect
- no effect
- positive
10 papers more in this group
See all 14 papers →nitrogen · quality: protein · Cucurbita (pumpkins)Results agree
1 paper in the same direction as this paper
This paper is about lacking the nutrient, so it counts the other way round here.
- positive
Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.