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Improved Resistance to Septoria in Superior Varieties (IMPRESSIV) - LK0945

The aim of this project is to enable wheat breeders to improve the effectiveness of breeding for resistance to septoria tritici blotch. This may be achieved by using genes which control disease effectively but do not have undesirable side-effects on plant performance. This will lead to the production of a steady supply of wheat varieties which have good resistance to septoria and are well-adapted to UK conditions.

The purpose of the IMPRESSIV project is to apply new knowledge of the genetics of resistance to septoria to improve methods of breeding for resistance in wheat varieties. This will support agriculture which is economically and environmentally sustainable.

Recent work on septoria at the JIC has been funded by DEFRA, Syngenta SA and by a successful DEFRA-sponsored LINK project, ‘Breeding for Improved Resistance to Septoria Tritici’ (BIRST). There are essentially two types of resistance to septoria.
· Specific resistance is effective against some isolates of the septoria fungus, Mycosphaerella graminicola, but not others. It is controlled by single genes (SR-genes) of large effect, one of which, Stb6, has been shown to follow the gene-for-gene relationship.
· Partial resistance is partially effective against all M. graminicola isolates tested and is mainly expressed in adult plants. Some genes for partial resistance (PR-genes) have been mapped, but a large proportion of partial resistance appears to be controlled by many genes with small effects, dispersed throughout the genome.
· In this concept note, R-genes means resistance genes in general, including SR-genes and PR-genes.
11 Objective(s)
11.1 Scientific objective(s)
(Please number 1, 2, 3 etc...)
There are three specific objectives. They are closely-related and inter-dependent, as the work plan indicates.
1. To investigate the cost to plant performance of resistance to septoria tritici blotch and of particular genes for septoria resistance.
1.1 To test whether partial resistance (PR) is correlated with a reduction in yield.
1.2 To test whether genes which confer greater PR incur a higher yield penalty.
1.3 To investigate whether the level of PR is related to the effectiveness of induced resistance.
2. To quantify the value of particular specific resistance genes for controlling septoria in the field.
2.1 To quantify, quickly and approximately, the value of four specific resistance (SR) genes for reducing septoria levels in the field.
2.2 To quantify more precisely the value of 12 SR-genes for field disease control.
2.3 To test whether combinations of SR-genes are especially effective in septoria control.
3. To increase the precision, and therefore the usefulness, of knowledge about genes for septoria resistance in UK wheat varieties.
3.1 To investigate the genetics of a source of septoria-susceptibility, apparently introduced into UK wheat varieties in the mid-1960’s.
3.2 To determine why the expression of the most important SR-gene, Stb6, differs among varieties.
3.3 To research the genetics of Pastiche, a fairly modern variety with very good resistance controlled by unknown genes.
3.4 To investigate the allelism of certain SR-genes which are beyond the capacity of BIRST to study.
3.5 To map the most useful SR genes as precisely as possible, using publicly-available microsatellite markers.
3.6 To postulate SR-genes in newly-released wheat varieties.

11.2 Interdependence of objectives
· In general, few objectives are inter-dependent.
· Objectives 1.2, 1.3 and 3.3 are dependent on the plant material developed under Objective 1.1.
· Objectives 2.1 and 2.2 are conceptually closely related but are not inter-dependent, as they will use different plant material.
· Objectives 2.1 and 3.5 will use the same plant populations which have already been developed.
· Certain methods will be used throughout the entire project, such as laboratory and glasshouse pathology tests for septoria resistance, using methods developed by JIC, and DNA marker technology.
Time-Scale and Cost
From: 2004

To: 2010

Cost: £759,309
Contractor / Funded Organisations
Home Grown Cereals Authority, Syngenta Crop Protection UK Ltd, Nickerson UK Ltd, Elsoms Seeds Ltd, Advanta, Sejet Planteforaedling I/S, SW Seeds Ltd, John Innes Centre (BBSRC)
Arable Farming              
LINK Programme              
Sustainable Farming and Food              
Sustainable Production              
Fields of Study
Arable Crops