Fine mapping of root lesion nematode (Pratylenchus thornei) resistance loci on chromosomes 6D and 2B of wheat.

Resistance QTL to root lesion nematode (Pratylenchus thornei) in wheat (Triticum aestivum), QRlnt.sk-6D and QRlnt.sk-2B, were mapped to intervals of 3.

A comparative gene analysis with rice identified orthologous group II HKT genes and their association with Na(+) concentration in bread wheat.

Background: Although the HKT transporter genes ascertain some of the key determinants of crop salt tolerance mechanisms, the diversity and functional role of group II HKT genes are not clearly understood in bread wheat. The advanced knowledge on rice HKT and whole genome sequence was, therefore, used in comparative gene analysis to identify orthologous wheat group II HKT genes and their role in trait variation under different saline environments.

Results: The four group II HKTs in rice identified two orthologous gene families from bread wheat, including the known TaHKT2;1 gene family and a new distinctly different gene family designated as TaHKT2;2.

QTL for resistance to root lesion nematode (Pratylenchus thornei) from a synthetic hexaploid wheat source.

A whole genome average interval mapping approach identified eight QTL associated with P. thornei resistance in a DH population from a cross between the synthetic-derived wheat Sokoll and cultivar Krichauff. Pratylenchus thornei are migratory nematodes that feed and reproduce within the wheat root cortex, causing cell death (lesions) resulting in severe yield reductions globally.

Genetic analysis of tolerance to the root lesion nematode Pratylenchus neglectus in the legume Medicago littoralis.

Background: The nematode Pratylenchus neglectus has a wide host range and is able to feed on the root systems of cereals, oilseeds, grain and pasture legumes. Under the Mediterranean low rainfall environments of Australia, annual Medicago pasture legumes are used in rotation with cereals to fix atmospheric nitrogen and improve soil parameters. Considerable efforts are being made in breeding programs to improve resistance and tolerance to Pratylenchus neglectus in the major crops wheat and barley, which makes it vital to develop appropriate selection tools in medics.

Characterization of resistance to Pratylenchus thornei (Nematoda) in wheat (Triticum aestivum): attraction, penetration, motility, and reproduction.

Lines from a cross between two wheat (Triticum aestivum) cultivars with contrasting resistance phenotypes to Pratylenchus thornei (Nematoda) were investigated to determine the stage at which resistance occurs. Host resistance was examined at nematode attraction to and penetration of roots and nematode motility, maturation, and reproduction within roots. There was no significant difference in the rate at which P.

Genetic analysis of tolerance to boron toxicity in the legume Medicago truncatula.

Background: Medicago truncatula Gaertn. (barrel medic) is cultivated as a pasture legume for its high protein content and ability to improve soils through nitrogen fixation. Toxic concentrations of the micronutrient Boron (B) in agricultural soils hamper the production of cereal and leguminous crops.

New insights into the infection process of Rhynchosporium secalis in barley using GFP.

Through the use of a Rhynchosporium secalis isolate transformed with the green fluorescent protein gene and LASER scanning confocal microscopy (LSCM), fungal development during the R. secalis/barley interaction was analysed. Each infection stage was investigated from 0.

Genetic structure of South Australian Pyrenophora teres populations as revealed by microsatellite analyses.

The aim of this study was to determine the genetic structure of South Australian field populations of the barley net blotch pathogens, Pyrenophora teres f. sp. teres (PTT) and P.

Identification of a chemically induced point mutation mediating herbicide tolerance in annual medics (Medicago spp.).

Background And Aims: Sulfonylurea (SU) herbicides are used extensively in cereal-livestock farming zones as effective and cheap herbicides with useful levels of residual activity. These residues can persist beyond the cropping year, severely affecting legumes in general, and annual medics in particular, resulting in reduced dry matter production, lower seed yields and decreased nitrogen fixation. A strand medic cultivar, Medicago littoralis 'Angel', has been developed via chemical mutagenesis with tolerance to SU soil residues.

Rust and downy mildew resistance in pearl millet (Pennisetum glaucum) mediated by heterologous expression of the afp gene from Aspergillus giganteus.

The cDNA encoding the antifungal protein AFP from the mould Aspergillus giganteus was introduced into two pearl millet (Pennisetum glaucum) genotypes by particle bombardment. Stable integration and expression of the afp gene was confirmed in two independent transgenic T0 plants and their progeny using Southern blot and RT-PCR analysis. In vitro infection of detached leaves and in vivo inoculation of whole plants with the basidomycete Puccinia substriata, the causal agent of rust disease, and the oomycete Sclerospora graminicola, causal agent of downy mildew, resulted in a significant reduction of disease symptoms in comparison to wild type control plants.

Expression of transgenic stilbene synthases in wheat causes the accumulation of unknown stilbene derivatives with antifungal activity.

The expression of foreign phytoalexins in a new host is thought to increase fungal resistance, since host-specific pathogens have not experienced selection for detoxifying or metabolising the novel antifungal compounds. Two resveratrol synthase genes vst1 and vst2 from grapevine (Vitis vinifera L.) and the pinosylvin synthase gene pss from pine (Pinus sylvestris L.