Dicotyledonous plant species

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). 

Root cultures can be established from root tips taken from many plants. Fast growing root cultures can be obtained from dicotyledonous plant species by infection with the microorganism Agrobacterium rhizogens. 

On average, the ash and macro element contents of the tested monocotyledonous and dicotyledonous plant species decreased from the end of April to the middle of... 

This chapter is concerned with describing methods involved in production and characterization of transformed root cultures from alkaloid-synthesizing dicotyledonous plant species. It should be noted that a large number of secondary metabolites which are not classed as alkaloids have been reported to be produced by transformed root cultures (reviewed by Hamill and Rhodes 1993). Thus the technology is apparently applicable to production of any secondary metabolite produced by roots of dicotyledonous plants. A list of alkaloids reported to be produced by transformed root cultures is presented in Table 1. 

In recent years it has become apparent that dicotyledonous plant species contain two distinctive forms of the enzyme acetyl CoA carboxylase, type I a single polypeptide of >220 kDa, and, type II a complex of smaller proteins BC, BCCP and CTa and p. To fully achieve the potential for the genetic manipulation of lipid products from crops a detailed understanding of fatty acid synthesis is required. This is dependent upon a full characterisation of the proteins involved, and more specifically on the pivotal enzyme ACCase. 

Despite increased citrate accumulation in roots of Zn-deficient rice plants, root exudation of citrate was not enhanced. However, in distinct adapted rice cultivars, enhanced release of citrate could be observed in the presence of high bicarbonate concentrations in the rooting medium, a stress factor, which is frequently associated with Fe and Zn deficiency in calcareous soils (235) (Hajibo-huid, unpublished). This bicarbonate-induced citrate exudation has been related to improved Zn acquisition in bicarbonate-tolerant and Zn-efficient rice genotypes (Fig. 9) (23S). Increased exudation of sugars, amino acids, and phenolic compounds in response to Zn deficiency has been reported for various dicotyledonous and monocotyledonous plant species and seems to be related to increased... 

The objective of this paper was to investigate the anticlastogenic and antitoxic effects exerted by HS of various origin and nature on several monocotyledon and dicotyledon herbaceous plant species treated with different mutagenic and phytotoxic compounds. 

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. 

Proanthocyanidins are plant phenolic biopolymers that consist of flavanoid monomer units. Two major classes of proanthocyanidins occur those that possess a resorcinol-pattern A-ring (Figure 1) and those that possess a phloroglucinol-pattern A-ring. The latter are by far the most common, occurring in a high proportion of monocotyledonous and dicotyledonous plants (1,2). The resorcinol-pattern proanthocyanidins are confined to a few genera of tropical or subtropical hardwoods and associated shrubby species (2), but are economically important, since the internationally commercially predominant wattle (3,4) and quebracho... 

The mint family (Labiatae or Lamiaceae) is a large group of dicotyledonous plants occurring worldwide in all types of climates except in extreme arctic and antarctic conditions. There are about 3,000 species in the mint family and 200 genera. The most diverse groups are the genus Salvia with 500 species, Hyptis with 350 species, and Scutellaria, Coleus, Plectranthus, and Stachys, each with 200 species. 

Lachance et al. [50] also conducted a suite of experiments to evaluate the potential of HMX to accumulate in several plant species. Consistent with other reports, the highest concentrations were found in the leaves, followed by roots and stems. The bioaccumulation potential for HMX was lower than that for RDX, and was independent of soil concentration. Indeed, Lachance et al. [50] showed that [14C]HMX was accumulated by different plant species with maximum BAF of 2.2. No distinction could be made regarding clear differences between monocotyledonous and dicotyledonous species in bioaccumulation potential under these conditions (Table 10.8). 

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