Effects of glyphosate on isolated maize mitochondria

The effects of the herbicide glyphosate (K+ salt) on isolated maize mitochondria have been investigated. Protein synthesis, oxygen uptake (state 3 and state 4 respiration) and passive swelling were inhibited at concentrations in the 10−6–10−2 M range. No decrease of the respiratory control ratio (RCR) or stimulation of ATPase activity by glyphosate (K+ salt) were observed. It is concluded that the previously reported decrease of the RCR and ATPase stimulation by glyphosate (isopropylamine salt) were probably due to the isopropylamine moiety or to impurities of the technical product

Present progress in the characterization of Triticum aestivum/Aegilops ventricosa transfer lines

In the laboratory of M. Metzlaff, genome specific DNA probes from Hordeum vulgare were cloned and characterized by H. Junghans. Regarding repeated DNA sequences our further investigations will concéntrate on the proofof alien chromatin in the wheat -Ae. markgrafii crossing material and on the enlargement of the investigation to their distribution in Poaceae species

Localización cromosómica de una peroxidasa de la Clase III de trigo.

En un estudio previo se caracterizaron, alinearon y relacionaron 20 genes que codifican para peroxidasas de trigo. Las secuencias deducidas de estos genes se agruparon en siete grupos, TaPrx108 a TaPrx114, de acuerdo a la similitud entre ellas y con peroxidasas de la Clase III de otras especies. Los genes correspondientes a tres de estos grupos (TaPrx111, TaPrx112 y TaPrx113) mostraron inducción en respuesta a la infección por Heterodera avenae en una línea de trigo resistente. Tres de los genes, TaPrx111-A, TaPrx112-D y TaPrx113-F, fueron localizados en el cromosoma 2BS y posiblemente estén ligados entre si. En el presente estudio, el gen de la peroxidasa TaPrx109-C, fue asignado al brazo largo del cromosoma 1B

Introgression of Aegilops triuncialis into Triticum aestivum. A progress report.

A. Delibes, I. López-Braña, M. Mena y F. García-Olmedo. 1988. Introgression of Aegüops triuncialis into Triticum aestivum. A progress report. An. Aula Dei 19 (1-2): 189-194. The wild grass Aegüops triuncialis (genomes CCUU) has been crossed with the tetraploid wheat Triticum turgidum (AABB) and the resulting ABCU sterile hybrid has been rescued with pollen from the hexaploid T. aestivum (AABBDD). Seven spikes from two hybrid plants were pollinated with pollen from T. aestivum cv. Almatense and 8 kernels were obtained. After five rounds of selfing, plants with 28 to 41 chromosomes have been derived. Low fertility (3-5 viable kernels per plant) was observed throughout the process. Further crosses to T. aestivum will be performed to obtain stable lines that will be screened for Ae. triuncialis genetic material with the aid of previously identified biochemical chromosome markers and specially developed DNA probes

Effects of introgressed 4Nv Aegilops ventricosa chromosome on yield and yield components in bread wheat.

Effects of introgressed 4Nv Aegilops ventricosa chromosome on yield and yield components in bread whea

Characterization of wheat/Aegilops ventricosa introgression and addition lines corresponding to the Mv genome.

Stable wheat-Aegilops introgression lines with 42 chromosomes (H-93), derived by repeated selfing from a cross (Triticum turgidum x Aegilops ventricosa) x T. aestivum, have been characterized using the following DNA probes and isozyme markers: (1) single or low-copy DNA fragments from Ae. ventricosa; (2) known cDNA probes corresponding to 1-thionin, monomeric -amylase inhibitor, the CM3 subunit of tetrameric -amylase inhibitor, and sucrose synthase from wheat; (3) anonymous cDNA probes from wheat that have been mapped by Sharp et al. (1989); (4) isozyme markers corresponding to aconitase, shikimate dehydrogenase, adenylate kinase, and endopeptidase. Meiotic metaphases of appropriate hybrids involving selected H-93 lines have been investigated by the Giemsa C-banding technique. The substitution of whole chromosomes [(5A) 5Mv; (4D) 4Mv; (5D) 5Mv; (7D) 7Mv] and chromosomal segments (1Mv; 3Mv; 5Mv; 7Mv) from the Mv genome of Aegilops ventricosa has been demonstrated. The distribution of selected markers among putative wheat-Ae. ventricosa addition lines has also been investigated. The 7Mv addition has been characterized for the first time, while the identity of the previously reported 5Mv and 6Mv additions has been confirmed

Analysis of Ascorbate Peroxidase Genes Expressed in Resistant and Susceptible Wheat Lines Infected by Heterodera avenae.

Changes in ascorbate peroxidase (APX) enzyme activity in response to nematode (Heterodera avenae) attack were studied in roots of three hexaploid wheat lines carrying Cre2, Cre5, or Cre7 nematode resistance genes and the susceptible Triticum aestivum cv. Anza. A spectrophotometric analysis was carried out with root extracts of infected plants 4, 7, 11, and 14 days after nematode inoculation using uninfected plant as control. APX induction in infected resistant genotypes was similar and higher than in the susceptible control. The introgression wheat/Aegilops ventricosa H-93-8 line, carrying the Cre2 gene, and its parental line H-10-15 as susceptible control were used to analyze whether this increase of activity was correlated with the induction of APX gene expression. Genes encoding cytosolic forms of APX were induced in roots of both lines in response to nematode infection. This induction took place both earlier and with greater intensity in the resistant line than in the susceptible one, and it was also higher in the root area at the site of nematode attachment

Peroxidase expression in a cereal cyst nematode (Heterodera avenae) resistant hexaploid wheat line.

The incompatible interaction between plant and pathogen is often determined by the hypersensitive reaction (HR). This response is associated with accumulation of reactive oxygen species (ROS), which results in adverse growth conditions for pathogens. Two major mechanisms involving either NADPH oxidases or peroxidases have been proposed for generation of ROS. Peroxidases (PER, EC 1.11.1.7), present in all land plants, are members of a large multigenic family with high number of isoforms involved in a broad range of physiological processes. PER genes, which are expressed in nematode feeding sites, have been identified in several plant species (Zacheo et al. 1997). A strong correlation between HR and PER activities at four and seven days post nematode infection, was detected in roots of wheat lines carrying Cre2, Cre5 (from Ae. ventricosa) or Cre7 (from Ae. triuncialis) Heterodera avenae resistance genes (Andrés et al. 2001; Montes et al. 2003, 2004). We have studied changes in root of peroxidase mRNAs levels after infection by H. avenae of a wheat/Ae. ven¬tricosa introgression line (H-93-8) carrying Cre2 (Delibes et al. 1993). We also report and classify the predicted protein sequences derived from complete peroxidase transcripts

Effects of the 4N(v) chromosome from Aegilops ventricosa on agronomic and quality traits in bread wheat

Advanced wheat lines carrying the Hessian fly resistance gene H27 were obtained by backcrossing the wheat/Aegilops ventricosa introgression line, H-93-33, to commercial wheat cultivars as recurrent parents. The Acph-N v 1 marker linked to the gene H27 on the 4Nv chromosome of this line was used for marker assisted selection. Advanced lines were evaluated for Hessian fly resistance in field and growth chamber tests, and for other agronomic traits during several crop seasons at different localities of Spain. The hessian fly resistance levels of lines carrying the 4Nv chromosome introgression (4D/4Nv substitution and recombination lines that previously were classified by in situ hybridisation) were high, but always lower than that of their Ae. ventricosa progenitor. Introgression lines had higher grain yields in infested field trials than those without the 4Nv chromosome and their susceptible parents, but lower grain yields under high yield potential conditions. The 4Nv introgression was also associated with later heading, and lower tiller and grain numbers/m2 . In addition, it was associated with longer and more lax spikes, and higher values of grain weight and grain protein content. However, the glutenin and gliadin expression, as well as the bread-making performance, were similar to those of their recurrent parent

Characterization of endosperm proteins and bread-making quality in wheat breeding lines carrying resistance genes for Mayetiola destructor and/or Heterodera avenae.

The experimental material included thirteen bread wheat-breeding lines that carry genes for resistance to M. destruc¬tor and/or H. avenae. The sources of these resistances are the wild species Ae. triuncialis and Ae. ventricosa (lines TR and H-93, respectively) (Delibes et al. 1993, 1997; Romero et al. 1998). We have determined the composition in HMW-glutenin subunits (related with bread-making quality), puroindoline proteins (related with hardness of grain), and waxy proteins (related with starch viscosity). In addition to, of prolamins by electrophoresis SDS-PAGE indicated the homogeneity of the lines