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All generations are evaluated in field under natural infection

and selected generations are tested under artificial infection.

For high pressure of diseases the spreader varieties are sown

between F

plots and in the disease nurseries in 2.5 m distance.

In F

we have used old Czech variety DIANA I, which is very

susceptible to all diseases. In later generations artificial

infections are applied in special hill plots disease nurseries,

every disease in one nursery with special spreader variety

(SPARTA for leaf rust, DANUBIA and WINZI for yellow rust

etc.) The mixture of races is used for infections. Yellow rust

resistance was overcomed 3 times in our country during last

25 years (races Ibis, Clement and Sleipner), the most serious

epidemic of yellow rust occured in 60's and 70's after

registration of susceptible varieties DIANA I, FANAL, SAVA

and ZLATNA DOLINA.

Leaf rust has become very important in the last years and

also in cooler regions. Stem rust is only dangerous in some

warmer areas and resistance genes Sr 31, Sr 29 have ramained

effective for the last 25 years.

Foliar fungal diseases of wheat caused by

S e p t o r ia ,

S t a g o n o s p o r a

and

P y r e n o p h o r a

species have become

economically significant for the wheat growing in Czech

republic, because the changes in the cropping systems.

S e p to ria

t r it ic i

and

P y re n o p h o ra

have occured more widely in last 5

years.

S e p to ria , S ta g o n o sp o ra

and

P yre n o p h o ra

spp. induce a

decrease in assimilation, developmental retardation, premature

leaf disiccation and reduction TKW. Yield losses may reach

30-50% (Horcicka, Markova, Hanisova et.all, in press).

Fusarium head blight resistance breeding has special

crossing programme with testing in artificial infection

conditions. Virus diseases (BYDV) are tested on the company

trials level at VURV Ruzyne.

Annually resistant varieties on 10% acreage in Czech

republic have saved about 200 mil. Kc (Hanisova et. al, 1997)

Screening for frost resistance under artificial test was

included in the Stupice breeding programme since 1973.

Annually about 2000 entries have been evaluated in

generations F2, F5, F

....Fn and parents lines prepared for

crossing. Methods for testing were adapted for breeding

purposes. Each entry is evaluated during winter in 2-3 field-

laboratory tests (FL-hardening under natural conditions and

laboratory freezing temperatures) and 2 laboratory tests (L-

adaptation of KOCH methode). In our tests for 95% probability

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