T. aestivum

Incorporation of [1-13C] Ferulic Acid. [1-13C] ferulic acid 5a, synthesized as previously described (26), was administered for 21-28 days to seedlings of L. leucocephala and T. aestivum following germination. The solid state C-13 spectra so obtained are shown in Figs. 2a and 2b, respectively. Note that these are difference spectra, obtained by subtraction of natural abundance resonances from that of the C-13 enriched samples, i.e., only C-13 enhanced resonances are evident. 

Figure 2. 13C NMR solid state difference spectra of (a) L. leucocephala and (b) T. aestivum (24) root tissue previously administered [1-13C] ferulic acid 5a. Fig. 2c shows the difference spectrum of a DHP polymer, derived from [1-13C] coniferyl alcohol 2a (29). CP/MAS spectra were obtained at 50 MHz on a Varian XL-200 Spectrophotometer equipped with a Doty Scientific MAS Probe. SSB = spinning side band.

As can be seen from Fig 2b, the solid state C-13 nmr spectrum of T. aestivum also shows sets of enhanced resonances at 61 ppm and 169.6-174.9 ppm respectively (24). However, their relative intensities are very different from that observed for L. leucocephala. Indeed, it can immediately be seen that very little reduction of the administered precursor to hydroxymethyl analogues (at 61 ppm) has occurred. On the other hand, the dominant resonances at 169.6 and 174.9 ppm are coincident with bound hydroxycin-namic acids (e.g. ferulic 5a) and its esters (31). Subsequent analysis of its isolated acetal lignin derivative (32) indicated that much of the lignin contained hydroxycinnamate residues (33). 

Incorporation of [2-13C] Ferulic Acid. Figs. 3a and 3b show the results obtained when [2-13C] ferulic acid 5b was administered to L. leucocephala (25) and T. aestivum L. (24), respectively. In the case of L. leucocephala, the dominant resonance observed at 82.7 ppm was coincident to that of... 

Incorporation of [3-13C] Ferulic Acid 5c. Figs. 4a and 4b show the results obtained following uptake of [3-13C] ferulic acid 5c to L. leucocephala and T. aestivum L., respectively the spectrum shown in Fig. 4c corresponds to a synthetic DHP polymer from [2-13C] coniferyl alcohol 2c. 

PCR reaction (25 yL final volume) contained Taq polymerase, 100 pmoles of the oligonucleotides primers, 2500 pmoles dNTP, T. aestivum genomic DNA (20 to 100 ng). 25 to 30 cycles were performed. A 1 min denaturation step at 94°C was followed by a hybridization step at 60 or 62°C for 0.5 to 2 min, followed by a 1.5 min elongation step at 72°C. The experiment was terminated by a 4 min step at 72°C. The PCR fragments were purified using Wizard PCR prep kit, either directly or after electrophoresis separation, and were cloned in the PGEM-T vector. The plasmidic DNA were first restriction analyzed, and then sequenced by MWG Biotech (Germany). 

Figure 13.5 Allelic variation in 4x wheats and their mutant forms. SDS-PAGE patterns of total seed proteins from (1 and 5) T. durum Des. And T. durum 788-control forms, (2, 3,4, 6, 7, 8, and 9 mutant forms type sphaerococcum). Lane 10 and 11 - T. aestivum. 12-LMW standart [13].

Figure 13.6 A-PAGE analysis of gliadins. Lanes 1, T. tauschii accessi 4-8, T. aestivum cvs Kite, RAC704, RAC746, Meeting, Cheyenne 9, T. tauschii accession CPI 110750 10, T. tauschii accession CPI 110856 and 11, T. tauschii accession AUS 18913 [20].

Figure 13.10 SDS-PAGE of seed storage proteins of T. aestivum L., cv S. ranozreika 2 and their mutant forms. Lane 1- control of T. aestivum, 2,4,5, 6, and 7 are lanes of mutant forms type sphaerococcum. The HMW-glutenin subunits are with high weight (more than 160,000), and well separated from other prolamins [13].

Wheat (Triticum aestivum), first leaf Wheat (T. aestivum), third leaf Wheat (T. aestivum), fifth leaf Yellow-poplar (Liriodendron tulipifera)... 

A feature shown by all developing seeds is the drop in levels of free gibberellin as the seed matures. This is preceded by one (e.g. T. aestivum [197], Echinocystis... 

Changing levels of cytokinin can be followed during seed development. Cytokinin in Z. mays kernels, for example, reaches a peak 11 days after pollination and declines considerably over another 10 days [120]. A similar pattern is found in T, aestivum (Fig. 3.31). One major and two minor peaks are seen in Pisum arvense (field pea) which coincide with the maximum volume of the endosperm and with the two periods of rapid growth of the whole seed and embryo [35]. The cytokinins of immature seeds are thought, therefore, to be involved in the phases of growth and development. Whether or not they also represent a store of hormone for later germination and growth is uncertain. 

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