Triticum species

The exudation of allelochemicals by living plants is one of the basic tenets of allelopathy theory and would be an indispensable component of any harnessed crop capacity against weeds.9 The exudation of relatively large amounts of key phenolics and benzoxazinoids from wheat (Triticum aestivum) cultivars (and other Triticum species) may well serve as an easily measured indicator of valuable... 

Gautier, M. R, P. Cosson, A. Guirao, R. Alary, and P. Joudrier. 2000. Puroindoline genes are highly conserved in diploid ancestor species but absent in tetra-ploid Triticum species. Plant Science 153 81-91. 

Another limitation to the studies in Table 1 is the small number of plant species tested. Primarily monocotyledonous plants have been studied, although McClure et al. (26) found ferulic acid inhibitory in soybean. The restriction of studies to monocots is probably because the mechanism of mineral absorption has been more fully elucidated with monocots. Harper and Balke (32) reported some minor differences in the inhibition of K+ absorption by salicylic acid among oats (Avena sativa L.), wheat (Triticum aestlvum L.), barley, and maize roots. 

Only four plant species, i.e., Vicia faba, Allium cepa, Pisum sativum and Triticum turgidum, responded adequately to the Feulgen procedure, and were considered for use in the successive experiments. These species, together with the corresponding mutagenic compounds used and the mutagenicity tests adopted (see below in Sect. 2.4.) are listed in Table 4. 

In addition to highly variable root to shoot ratios (0.01-1.22) the use of these values is complicated by (1) ratios that are hybrid, variety, and species-specific and (2) below-ground allocations that are impacted by stress (Herbert et al. 2001 Bradford et al. 2005 Amos and Walters 2006 Johnson et al. 2006). For example, Johnson et al. (2006) used root to shoot ratios of 0.82,0.55, and 0.62 for wheat (Triticum aestivum), com, and soybean (Glycine max), respectively whereas Amos and Walters (2006) reported that root to shoot ratios increased with N and P deficiencies and decreased with increasing water stress, population, shade, and soil compaction. 

Malcherek, K., Breuer, J., Schumphan, L, and Schmidt, B., 1998, Metabolism of 4-nitrophenol in asepticaly cultivated plants of the species wheat (Triticum aestivum L.), soybean Glycine max L.), wild oat Avena fatua L.) and com cockle Agrostemma githago L.). J. Plant Physiol. 153 192-199. 

To identify ferulic acid, Liebl and Worsham ( ) used weed species in their bioassays that were actually growing in association with wheat (Triticum aestivum L.) in the environment. Thus, there is diversity in terms of which plant species are used in bioassays to indicate biological activity. 

The most common wheat species used in food production is ordinary wheat, also called bread wheat (Triticum aestivum). It is an allohexaploid (AABBDD), in which the genomes were obtained by spontaneous hybridization of T. turgidum (AABB) and Aegilops tauschii (DD) about 10,000 years ago (Vasil, 2007). Other grown wheat species are tetraploidal durum wheat T. durum, used in pasta production and small amounts of hexaploidal spelt T. spelta and tetraploidal T. polonicum (Curtis et al. 2002). 

The Major Crops Of The World. Mangelsdorf,xhas said that since the dawn of history man has used about 3000 species of plants for food. Perhaps 150 of these are in world commerce today, but only 10 percent of these really feed the people of the world. Mangelsdorf1s 15 species include five cereals rice (Oryza sativa), wheat (Triticum spp.), maize (Zea mays), sorghum (Sorghum cerealeTt and... 

Aach, H., Bose, G. and Graebe, J.E. (1995) Ent-kaurene biosynthesis in a cell-free system from wheat (Triticum aestivum) seedlings and the localisation of ent-kaurene s)mthetase in plastids of three species. Planta, 197, 333-42. 

SENSITIVE PLANTS Species of the getter a Pioea, Pinux, Larix, Tilia, Fagus, Malus, Hordeum, Avena, Secale, Triticum 0.09 0.08 0.40 0.35... 

In a first series of experiments Avena sativa, which had been a weed in rye fields before it became a so called secondary crop, Triticum aestivum and Vida faba L. roots or whole plants as model systems were incubated in presence of BOA [179]. All the three species were able to absorb the substance when 100 pM were applied. With 500 pM BOA Vicia faba failed in taking up and root tips were killed by the compound as indicated by blackening during the course of incubation. The cereals were still able to absorb BOA, Triticum aestivum without and Avena sativa with a lag phase of 10 - 15 h. In Avena sativa the uptake seems to be an active process, which succumbs under oxygen deficiency and, as ascertained by incubations in presence of only IpM BOA, takes place against the concentration gradient (Schulz and Wieland, unpublished). 

Phenoxazinone production was as well observed in incubation media of Secale cereale, but not in such of Vida faba and Triticum aestivum [180]. The compounds can be detected is well in incubation media of several dicotyledonous species [187]. Since surface sterilization of oat caryopses with NaOCl did not prevent phenoxazinone production, it is possible that the responsible microorganism(s) are located within the caryopses. Phenoxazinone itself has an inhibitory effect on oat radicle elongation, probably caused by intercalation of the phenoxazinone ring system to DNA, as it is known from the phenoxazinone ring system of the transcription inhibitor actinomycin D, an antibiotic produced by Strepto-myces species. 

Marshall D, Tunali B, Nelson LR. Occurrence of fungal endophytes in species of wild Triticum. Crop Sci 39 1507-1512, 1999. 

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