Genetic base broadening for cereals: problems and goals. Vytautas Ruzgas Lithuanian Institute of Agriculture

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1 Genetic base broadening for cereals: problems and goals Vytautas Ruzgas Lithuanian Institute of Agriculture

2 The main reason why we should think about genetic base broadening The majority of top varieties have quite narrow genetic pedigree. From the biological point of view it is not desirable Resistance to pathogenes is a permanent problem. Resistance genes are effective not forever New goals require a new gene pool for plant breeding.

3 Some examples: Common bunt is a limiting factor for organic farming. For a long time it was not a problem due to seed treatment in conventional agriculture For the development of varieties resistant to common bunt the breeders need of appropriate parental material For new farming systems (ploughless etc.) farmers need a new varieties resistant to Tan spot, Fusarium etc. The range of varieties available for farmers and genetic collections is rather small. Climate warming causes a new problems Roots: a new area for research acctivity

4 Thous. ha Area under organic farming in Lithuania 70, ,0 4,0 4,7 6,4 8,8 23,3 43, planas

5 Susceptibility to Common bunt in winter wheat collection (more than 2000 varieties and lines were investigated over the period ) 80,0 70,0 68,4 60,0 50,0 % 40,0 30,0 20,0 10,0 0,0 0,1 0,5 1,0 10,0 20,0 0 0,1-5,0 5,1-10,0 10,1-30,0 30,1-50,0 50,1-100,0 Infecion %

6 Genetic base broadening possibilities using varieties of distant geographic origin To obtain more diverse gene pool for breeding programmes the Lithuanian Institute of Agriculture joined the International Facultative and Winter Wheat Observation Nursery project, initiated by CIMMYT. The varieties for this project were collected from distant origin, majority from South regions Since 1993 more than 3000 varieties and lines have been investigated Some varieties were included in the crossing combinations to get the initial material for further crosses

7 What was the adaptation of winter wheat varieties from Southern countries under Lithuanian conditions? - High air humidity - Chilly summers - Changeable air temperatures in winter, sometimes -25..C 0

8 Varieties (Investigated 940 varieties) Varieties from South regions: susceptibility to winter conditions, Lithuania, Širvinta = 0-20 % 2 = % 3 = % 4 = % 5 = % 6 = % 7 = % 8 = % 9 = % Suscepibility, scores

9 Varieties (investigated 851) 250 Grain yield, Standard early variety) 85 Standard late variety) Grain yield, t/ha 3

10 (Varieties,%) Protein content of winter wheat varieties from South countries , , Širvinta ,3 < 10.5 % % % > 14 % Grain protein content

11 Varieties Wheat from South regions: resistance to diseases, Standartd, late 210 Standard, early Septoria tritici Erysiphe graminis resistantat, 9 - very susceptible

12 The majority of the winter wheat varieties from arid climate countries exhibited sufficient winter hardiness. The varieties from arid climate countries were noted for early maturity. This trait is valuable in the context of climate warming in the Baltic see region. Resistance to Drechslera tritici-repentis is a promising trait, but further studies are needed. The greatest constraints of the varieties from arid climate countries to be included in breeding programmes are low grain yield and susceptibility to powdery mildew.

13 Starch quality Starch quality of winter wheat grain is a recent problem. Starch producing industry requires wheat grain characterised by: - high starch quality: -higher share of granules > 10 µm - waxy wheat, whose starch consists of amyl pectin and has no amylase

14 Starch granules: distribution of size The size of granules is a limiting factor of starch quality, properties of dough, output of alcohol and other properties

15 Section of waxy wheat grain Waxy wheat starch has no reaction with iodine

16 Waxy wheat is desirable in dietary bread- making For peoples who do not tolerate the gluten Ordinary wheat Waxy wheat Blending of waxy and ordinary wheat

17 The main limiting factors in breeding programmes Most starch type varieties have low content of big- sized granules Most waxy wheat varieties are low yielding and susceptible to diseases, lodging problems etc. Great part of waxy wheat varieties are not fully waxy in all 3 genomes Limited gene resources

18 Collection of waxy and exotic wheat

19 Farmers are interested only in high yielding top varieties

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21 The ultimate task for pre-breeding: development of new attractive varieties with improved genetic value

22 U Thank you for attention!