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Developing Winter Wheat Germplasm of Woodlands EcotypeYu,V Olshanski, II.K Kotko,1 L.N Sheredeko,1 and VP. Andriyash'During the past two decades harmful diseases of winter wheat capable of decreasing yield by 30% andmore have spread widely on the right-bank forest-steppe zone and the woodlands of Ukraine, These areseptoria, certain types of roots rots. powdery mildew and enzyme-mycosis depletion of grain, Theirinvariable epiphytotlcs revealed the absence of resistant genotypes in the assortment of winter wheatvarieties cultivated in the region. Due to this a great number of cultivars were introduced into the region.including poorly adapted ones, Suffice it to say that more than 20 cultivars have been Included in the statevariety register list in this zone. This multivarietal phenomenon affects all-state systems of elite seedproduction negatively.The lack of breeding material resistant and/or tolerant to above mentioned diseases and adapted towoodland conditions represents a major breeding challenge. Since 1980 much attention has been paid todisease resistance, along with productivity and grain quality, Up to 3000-5000 entries were screenedannually, including 300-800 from collection nurseries.It was found that among materials being used in the breeding process there are no genotypes which areabsolutely resistant to root rots and septoria. Therefore one should only consider the degree of susceptibilitywhich does not cause serious yield losses. For most types of root rots and septaria, a level of 10-20% wasestablished and for powdery mildew, 25-30%. In 1981-1988 two cultivars relatively resistant to mostaggressive diseases were identified (Table 1). In addition varieties Capelle Desprez, VPM-1, Roazon(France); Walda Holma (Sweden); Vala. Siavia (Czech Republic), Remus, Pivot (Germany); Fuzz. Oasis.Arthur (USA), some accessions of T spe/ta. Aegi/ops cilindrica; wheat-AgroPYron and wheat-Aegi/opsintermediate forms also demonstrated some resistance. However, when being crossed many of them causeproblems due to poor winter hardiness and bread making properties. Cultivars from Mironovka WheatInstitute as well as those from Russia (Tambovitsa 12, Don 85, Severnaya zarya) and Ukraine (Donetskaya48, Kharkovskaya 50, Kharkovskaya 90. Strumok Odesskiy) are the best parents for crossing.The weather conditions of 1994 allowed excellent differentiation for winter hardiness; data for some entriesidentified are presented in Table 2. The combination of traits mentioned above makes it possible to developnew breeding material representing woodlands ecotype.A number of resistant varieties and lines have been developed by the department of breeding and seedproduction of the Ukrainian Academy of Agrarian Sciences. These are Polesskaya 87, Polesskaya 90,7126-93 developed under artificial disease inoculation (Table 3).Variety Po[esskaya 90 has been released in the region of Kiev Breeding Center. It is characterized by highdisease resistance with comparatively insignificant advantage in yield over the check (+0.22 tlha). The grainquality of this variety is very good and it is classified as valuable quality wheat. It does not need chemicaltreatment against diseases and therefore is environmentally safe. The area planted under Polesskaya 90totals about 50,000 ha., Ukrainian Institute of Agronomy, pia Chabany, Kiev reg, 255205 Ukraine.46