Search results for "cotyledon"
showing 10 items of 21 documents
Regeneration of herbicide-tolerant black locust transgenic plants by SAAT
2003
A protocol based on SAAT (sonication-assisted Agrobacterium-mediated transformation) has been developed to obtain herbicide-resistant transgenic black locust (Robinia pseudoacacia L.) plants. Cotyledon explants were co-cultivated with Agrobacterium AGL1 strain carrying the pTAB16 plasmid (bar and gusA genes). The effects of bacterial concentration (OD550 of 0.3, 0.6, 0.8) and method of infection (sonication vs immersion) on bacterial delivery were determined by assaying cotyledons for transient beta-glucuronidase expression 3 days after infection. SAAT increases transient expression efficiency especially at an OD550 of 0.6. After determining bacterial concentration and infection method, oth…
High‐resolution histographical mapping of glucose concentrations in developing cotyledons of Vicia faba in relation to mitotic activity and storage p…
1998
Summary Previous studies provided evidence that the carbohydrate status triggers developmental processes in the growing cotyledons ofVicia faba. We describe here the high-resolution mapping of glucose concentrations in tissue sections of developing faba bean cotyledons by quantitative bioluminescence and single-photon imaging. Patterns of local glucose distributions are compared with tissue cell type, mitotic index and the distribution pattern of starch. During cotyledon differentiation, gradients in the glucose concentration emerge which are related to the particular cell type. Higher concentrations are found in non-differentiated premature regions of the cotyledon whereas mature starch-ac…
Effects of Acifluorfen-methyl on cucumber cotyledons : porphyrin accumulation
1988
Abstract The nitrodiphenyl ether herbicide acifluorfen-methyl and the pyridine derivative LS 82-556 induce porphyrin accumulation in green cucumber cotyledons. When experiments are done with intact plants absorbing the herbicide through the roots, that accumulation is light-dependent. 3-(3,4-Dichlorophenyl)-1,1-dimethylurea (DCMU) which prevents cellular damages under these conditions (M. Matringe and R. Scalla, Pestic. Biochem. Physiol. 26 , 150 (1986), also inhibits porphyrin accumulation. In contrast, when detached cotyledons are cut into pieces and floated on herbicide solutions, porphyrins accumulate in the dark. Accordingly, DCMU does not inhibit porphyrin accumulation or protect the …
Stimulation of root and somatic embryo production in Euconymus europaeus L. by an inhibitor of polyamine biosynthesis
1995
In vitro formation of roots and somatic embryos is obtained from cotyledon explants of a Spindle tree (Euonymus europaeus L.) cultured on two different media: a medium inducing callus formation and the production of roots, and a medium inducing callus formation, root and somatic embryo production. We studied the effects of α-difluoromethylornithine (DFMO), a specific, irreversible inhibitor of ornithine decarboxylase (ODC) on root and somatic embryo production, growth and titers of putrescine in Euonymus explants and explant-derived calli. Early changes in putrescine levels were detected in both cultures before the visible emergence of roots or somatic embryos. DFMO rapidly inhibited putres…
Biomechanics and functional morphology of a climbing monocot.
2015
Climbing monocots can develop into large bodied plants despite being confined by primary growth. In our study on Flagellaria indica we measured surprisingly high stem biomechanical properties (in bending and torsion) and we show that the lack of secondary growth is overcome by a combination of tissue maturation processes and attachment mode. This leads to higher densities of mechanically relevant tissues in the periphery of the stem and to the transition from self-supporting to climbing growth. The development of specialised attachment structures has probably underpinned the evolution of numerous other large bodied climbing monocot taxa.
Comparison of iron acquisition from Fe–pyoverdine by strategy I and strategy II plants
2011
; Iron is an essential micronutrient for plants and associated microorganisms. However, the bioavailability of iron in cultivated soils islow. Plants and microorganisms have thus evolved active strategies of iron uptake. Two different iron uptake strategies have been described in dicotyledonous and monocotyledonous graminaceous species. In bacteria,this strat-egy relies on the synthesis of siderophores. Pyoverdines, a major class of siderophores produced byfluorescent pseudomo-nads, were previously shown topromote ironnutrition of the dicotyledonous species ArabidopsisthalianaL.(Heynh.), whereas contradictory reports were made on the contribution of those siderophores to the nutrition of g…
Direct Organogenesis from Cotyledons in Cultivars of Citrus clementina Hort. ex Tan
2011
An efficient protocol to induce shoot buds regeneration in Citrus clementina cultivars (“Monreal”, “SRA 63” and “SRA 64”) by direct organogenesis has been developed using cotyledons as explants. Cotyledons transversely cut in three segments and entire ones were cultured on Murashige and Skoog (1962) solidified medium containing vitamins, 500 mg·l−1 malt extract, 50 g·l−1 sucrose and supplemented with three different concentrations of BAP (8.8, 13.2 and 17.6 μM). In all three cultivars the entire cotyledons showed more shoot morphogenic potential than transversely cut ones and after 60 incubation days the optimum BAP concentration was 17.6 μM in “Monreal” (50% ± 2.89% of frequency regenerati…
Differences in the activity and distribution of peroxidases from three different portions of germinating Brassica oleracea seeds
2002
Peroxidase (POD, EC 1.11.1.7) activity, cellular localization and isozyme patterns were investigated in the seed integument, cotyledon and embryo axis of Brassica oleracea cv. Cappuccio during pregermination and seedling growth. Seeds started to germinate after 24 h of imbibition. POD activity was localized in the pigmented layer of the integument and in procambial strands of the cotyledon and embryo axis in the first 24 h of imbibition. It was localized in the integumental cells of palisade, pigmented and aleurone layers and in epidermal, meristematic, procambial cells and xylem elements of the root and hypocotyl after 48 h of imbibition. POD activity increased during germination and early…
In vitroplant regeneration and gene transfer in the wild tomatoLycopersicon cheesmanii
2001
SummaryThis paper reports on protocols for in vitro plant regeneration, gene transfer and on shoot salt tolerance from two accessions of L. cheesmanii (Riley). Shoot organogenesis was achieved on media with zeatin or BA/IAA combinations. The two accessions tested, LA1401 and LA530, showed differences in both their aptitude to regenerate and their salt tolerance in vitro. The accession LA530 had a higher organogenic potential than LA1401 (97% vs. 80% of organogenic explants). In contrast, none of the LA530 isolated shoots rooted when cultured in full strength MS-modified medium supplemented with 200.mM NaCl while 93% of shoots from LA1401 formed roots. Finally, Agrobacterium-mediated transfo…
In Vitro Propagation of Sideritis angustifolia Lag.
1987
Summary Hypocotyl, root and cotyledon explants from 30 day old seedlings of Sideritis angustifolia Lag. were cultured on Murashige and Skoog nutrient medium. Organogenesis of roots and shoots was induced with treatments containing BA or KIN in combination with NAA, IAA or 2,4-D, however, those combinations including NAA and BA were optimal. Most regenerated shoots developed roots when transferred to medium without growth regulators. Rooted plantlets were successfully transplanted into soil.