Plant dicotyledonous

F. Shinmachi, I. Flasegawa, A. Noguchi, and J. Yazaki, Characterization of iron deficiency response system with riboflavin secretion in some dicotyledonous plants. Plant Nutrition for Sustainable Food Production and Environment (T, Ando, K. Fujita, T. Mae, H. Mat.sumoto, S. Mori, and J. Sekiya, eds.), Kluwer Academic Publishers, Dordrecht, 1997, p. 277. 

Especially in dicotyledonous plant species such as tomato, chickpea, and white lupin (82,111), with a high cation/anion uptake ratio, PEPC-mediated biosynthesis of carboxylates may also be linked to excessive net uptake of cations due to inhibition of uptake and assimilation of nitrate under P-deficient conditions (Fig. 5) (17,111,115). Excess uptake of cations is balanced by enhanced net re-lea,se of protons (82,111,116), provided by increased bio.synthesis of organic acids via PEPC as a constituent of the intracellular pH-stat mechanism (117). In these plants, P deficiency-mediated proton extrusion leads to rhizosphere acidification, which can contribute to the. solubilization of acid soluble Ca phosphates in calcareous soils (Fig. 5) (34,118,119). In some species (e.g., chickpea, white lupin, oil-seed rape, buckwheat), the enhanced net release of protons is associated with increased exudation of carboxylates, whereas in tomato, carboxylate exudation was negligible despite intense proton extrusion (82,120). 

The use of microbial siderophores by dicotyledonous plants appears to involve uptake of the entire metallated chelate (42-44), or an indirect process in which the siderophore undergoes degradation to release iron (45). As demonstrated in initial studies examining this question, there was concern that iron uptake from microbial siderophores may be an artifact of microbial iron uptake in which radiolabeled iron is accumulated by root-colonizing microorganisms (46). Consequently, evidence for direct uptake of iron from microbial siderophores has required the use of axenic plants. In experiments with cucumber, it was shown that the microbial siderophore ferrioxamine B could be used as an iron source at concentrations as low as 5 pM and that the siderophore itself entered the plant (42). 

The latter substance, as is well known, interferes with nuclear division in plants. Temple-man and Sexton (35) showed that, contrary to the effects of the phenoxyacetic acids, the arylurethanes destroy cereals more readily than the dicotyledonous plants. 

I The distinction between mono-and dicotyledonous plants is quite simple monocotyledons are flowering plants which have only one seed leaf, and usually have parallel-veined leaves, flower parts in multiples of three, and no secondary growth in stems and roots, whereas dicotyledons are flowering plants with two seed leaves (cotyledons), net-veined leaves, flower parts in fours and fives, and in woody plants have cambium, a layer of formative cells between the wood and the bark the cells increase by division and differentiate to form new wood and bark. 

The seeds of dicotyledonous plants have two cotyledons, or seed leaves, which are part of the embryo. The cotyledons usually are the main storage tissue, although in some plants (such as castor bean) the endosperm also has a storage function. During development in the field, seeds gradually accumulate storage oils, proteins and carbohydrates (Table 3.1). In the seed, the cotyledon structure is relatively simple. The remainder of the embryo, the embryonic axis, consists mostly of undifferentiated cells, but provascular tissue can be detected that develops into vascular tissue in the seedling. 

Potato type II (Potll) inhibitors are disulfide-rich peptides of approximately 50 amino acids in size. They were first discovered in leaves, seeds, and other organs of Solanaceae and are a source of much interest as plant defense proteins. Recently, Barta et analyzed expressed sequence tag (EST) and genomic data and discovered 11 genes that code for Potll inhibitors in various monocotyledonous and dicotyledonous plants. Potll inhibitors are expressed as large precursor proteins that contain up to eight sequence repeats of the inhibitor precursor. In one particularly fascinating case from the ornamental tobacco (N. data), the precursor adopts a circular permuted structure.Barta et al. observed that genes outside the Solanaceae family seem... 

From June to September 1971, 74 dicotyledonous species were collected on the 3 km Test Area, and 33 additional species were found during the June 1973 survey. The most Important dicotyledonous plants found Invading the test area were rough buttonweed, Dlodla teres Walt poverty weed, Hypericum gentlanoldes L. and common polypremum, Polypremum procumbens L. 

The secondary metabolites of the endophytic fungi associated with dicotyledonous plants (dicots) are chemically diverse (Table 1). There is an equal diversity in the activities of these compounds, including antibacterial, antifungal, nematicidal, phytotoxic, cytotoxic, antineoplastic, anti-insectant, anti-herbivory, and a variety of other activities. The compounds isolated, structurally elucidated, and explored biologically in the short time since previous reviews continue to display that same wide array of chemical and biological diversity. 

Steiner U et al., Molecular characterization of a seed transmitted clavicipitaceous fungus occurring on dicotyledoneous plants (Convolvulaceae), Planta 224 533— 544, 2006. 

Flecking on the upper surface of leaves is a common symptom of ozone injury on dicotyledonous plants. A single fleck is a small line of dead tissue that appears white, yellow, or brown... 

Smith, B. G., Harris, P. J., Melton, L. D., Newman, R. H. (1998). Crystalline cellulose in hydrated primary cell walls of three monocotyledons and one dicotyledon. Plant Cell Physiol, 39, 711-720. 

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