Genetic basis of loose smut resistance in Ukrainian, Russian, and U.S. winter and spring wheats.

S.V. Rabinovich, I.N. Chernyaeva, E.J. Afonskaya, and E.M. Dolgova.

Resistance of T. aestivum L. to loose smut (Ustilago tritici Pers.) was studied during 1991ñ95 by artificial inoculation. The level of infected heads was 70 % in winter and 38 % in spring wheats. Twenty-five percent of the winter wheat cultivars and 10 % of the spring wheats were loose smut-resistant

Winter wheat. Wheat cultivars developed at the Institute for Plant Breeding and Genetics (SGI) in Odessa take a special place among the resistant lines. The first investigations on disease-resistance breeding in Odessa were by A.A. Sapegin at the Academy for Sciences of the USSR. In the 1930s, he acknowledged the urgency for research on the breeding of resistant cultivars. For the first time in the Ukraine, he artificially infected plants and developed the first domestic spring wheat cultivar, Milturum 274, with resistance to loose smut and bunt.

Among modern varieties of Odessa breeding, descendants from the 1930s cultivar Zemka, resistant through all years of its cultivation (1929ñ60), possess high resistance to U. tritici (Krivchenko 1984). Cultivars with Zemka in their pedigrees include Odeska 16 (ODS, a combination of hybrid lines selected from Odeska 12 `Zemka/Hostianum 237'), Odeska 51 (ODS 16 /Bezostaya 1 (BEZ)), Priboy (BEZ 1/ODS 16), and Odeska 66 (Aurore (AU)/ODS 51). These cultivars were used widely in production and breeding and became progenitors of the loose smut-resistant or moderately resistant cultivars Odeska Polukarlikova; Odeska 75; Stepnyak (selected from Priboy); the Moldavian wheats Beltskaya 60 and Piticul; the Krasnodar cultivar Saratnitsa; and the Tatarstanian wheats Meshinskaya (in the pedigree of Chernomorka, a derivative of ODS 16) and Meshinskaya 3.

In Odessa, in the 1980ñ90 cultivars Obriy, Olviya, and their descendants Zolotava and Belchanka 9 (Moldova), and Rufa (Russia), the resistance from ODS 16 is combined with the resistance from other cultivars. These cultivars include resistance from North American cultivar Red River 68 and the Mexican cultivars Lerma Rojo 64, Sonora 64, INIA 66, Jaral 66, Azteca 67, and others. Their loose smut resistance is from the American spring wheats Hope (pedigree: Russian T. dicoccum/Marquis//Prelude, with three dominant genes (Tingey et al. 1934) and Thatcher) and Jumillo from Italy (pedigree: T. durum/ Marquis//Kanred (a winter wheat)/Marquis.

Babajants and coworkers (1990) reported that the line FERR 220-85 (LR 64/2*KVZ//Koral odesky) had high loose smut and bunt resistance and that Peresvet (LR 64/2*KVZ) was the donor of the loose smut resistance (Babajants 1988). The combination of the Hope and Thatcher genotypes with the wheat-rye translocation 1BL·1RS in Kavkaz is implicated in this property.

Odessan cultivars Yubileyna 75, Chervona, and Odom, released in the 1990s, combine resistance of LR 64/KVZ with the resistance of ODS 16, Hope, and Thatcher. Yympel odesky inherited its resistance from the last three wheats and immunity from `Odeska 95 ODS 16/AU'. Cultivars of the Odesa Institute for Agriculture in the 1980ñ90s, Khlebodarka, Trofimovka, Burevestnik odesky, and Odeska ostista, selected at the SGI and older loose smut-resistant, Moldovian cultivars Belchanka and Moldova are the descendants of Erythrospermum 127. This cultivar gained its resistance from ODS 3, a descendant of Krimka (synonym Turkey).

An analysis of the pedigrees of resistant cultivars from the 1970ñ80s (Belotserkovska (BEL) 41, BEL 47, BEL 51, BEL 18, BEL 7, and Belotserkovska intensivna), and also the Byelorussian cultivar Suzorje (a descendant of Osetinskaya 3) released in the early 1990s, suggests that the North American cultivar Kawvale, with two dominant and three recessive loose smut-resistance genes, is the basis of resistance of all the aforementioned cultivars.

Krasnodarskaya 39 (pedigree: BEZ 1/Saratovskaya 3 (Hostianum 237/rye-wheat hybrid 434-151)) is one of the most effective sources of resistance. This cultivar was immune to loose smut in 4 years of testing. Hostianum 237 and the ryeñwheat hybrid 434-151 most probably are the sources of resistance. Among descendants of Krasnodarskaya 39 developed in 1980ñ90s are the resistant cultivars: Zimdar; Severokubanka (ODS 3 also in the pedigree), the Severokubanka derivatives Bezenchukskaya 380 and Pavlovka), Pavlovka descendants, and Spartanka. The Byelorussian wheats Kapylanka and Skifjanka (Hope and Thatcher also in pedigree) were selections from Spartanka.

Resistance for loose smut from A. glaucum, in combination with resistance for bunt, is present in Zarya, Yantarnaya 50, Moscowskaya nizkostebelnaya, Moscowskaya 70, Inna (immune to loose smut), and Zvezda. Agropyron glaucum is present in the pedigrees of two loose smut-resistant Siberian cultivars, Albidum 12 and Sibinka.

Loose smut resistance in North American cultivars Century (HRWW, Oklahoma) and Auburn (SRWW, Indiana), bred in 1980s, is caused by the presence of A. elongatum genetic material in their pedigrees. Of wheats bred in the 1970s, Larned (HRWW, Kansas) inherited its resistance from Hope, and Titan (SRWW, Ohio) and its parental cultivar from the 1950s Newsar (SRWW, Indiana) from Trumbull (SRWW). Trumbull, which was released in Ohio at the beginning of the 1900s, has a loose smut-resistance gene (Caldwell et al. 1947).

Spring wheat. All wheats bred in 1980ñ90s at the Yurjev Plant Production Institute are loose smut resistant. These cultivars include: Kharkivska 4, Kharkivska 6, Kharkivska 10, Kharkivska 12, and Kharkivska 16. All are moderately resistant to bunt also. The aforementioned cultivars originated from the cross `PPH 56 (A. glaucum in pedigree)/Selkirk', which is the basis of both the loose smut and bunt resistance. In addition, Saratovskaya 29 (UtS­29) is present in the pedigrees of Kharkivska 18 and Kharkivska 8, which are immune to loose smut. Kharkivska 8 also is resistant to bunt.

The source of resistance to loose smut in Russian cultivars of 1970ñ90s Spektr, Budimir, Kommunar 2, Zoryan, and Omskaya 22 and the Kazakhstanian cultivars Komsomolskaya 29, Kazakhstanskaya 19 (ODS 16 also in pedigree), Ulbinka 30, and Mereke, probably is Saratovskaya 29.

Among Russian wheats bred in the 1980ñ90s, those resistant to loose smut are Omskaya 20 and Sibirskaya 65 (derivatives of Graecum 114 with A. glaucum in the pedigree), Isheevskaya, Erythrospermum 817 (ERSP), and ERSP 819 (descendants of Zhygulevskaya (DC II 21-44 and sibs of Thatcher in pedigree) and ERSP 810 (of both sources). Kurskaya 263, Voronezhskaya 10, Vavilovskaya (selected from Selkirk), and Tselinnaya 24 (from Thatcher) also are resistant to loose smut.

Spring durum wheat resistance to common bunt and fruit fly injury in the northeastern forest-steppe region of the Ukraine.

E.M. Dolgova, N.K Ilchenko, and T.U. Markova.

For the breeding of cultivars resistant to common bunt (Tilletia tritici) and fruit fly injury (Oscinella frit, O. pusilla), 150 spring durum wheat cultivars were studied during 1991ñ1995. The tested wheats were inoculated with T. tritici. The average infection level for susceptible cultivars was 70 %. Highly resistant (< 10 % bunted heads) cultivars were Odeska 116 from the Ukraine; 207H3, Leucurum 812H2, Leucurum 813H8, and Atlant 24 from Russia; Kazakhstanskaya yantarnaya and Melanopus 90 from Kazakhstan; GK Basa from Hungary; Romeo, Kidur, and Primadur from France; Rodeo, Quadruro, and BC3 from Italy; Boohai from Ethiopia; Medora from Canada; Lloyd, and the lines D6962, D7733, D7798, D7812, D7958, D7983, D79103, D79120, D79122, D79168, D79209, D8016, D8019, D803, D8092, D81151, and D8257 from USA; and Altar 84 and CD28164 from Mexico. These cultivars are descendants of resistant and moderately resistant varieties. For example, Lloyd and Medora have resistance to common bunt in the climatic conditions of the Ukrainian Forest-Steppe, although ancestors Ward and Cando were moderately resistant, as were Edmore and Vic.

Resistance to fruit fly injury in the spring durum wheats was evaluated. The degree of injury was expressed as a percentage. For the tolerance to injury we use the coefficient of tolerance (CT), the ratio of the amount of productive stalk to the amount of injured stalk. Injury in the susceptible cultivars equaled an average of 64 % and their CT was 0.5. The best cultivars of medium resistance were injured no more than 35 % and their CT exceeded 1.5. These were Kharkivska 37 and Kharkivska 23 from the Ukraine; Novodonskaya, 35783-81, 3428C-88, Elan, Krasnokoutka 10, Bezentchoukskaya 182, Hordeiforme 816, Hordeiforme 1131, HB-1, and HT-32 from Russia; and Damsinskaya and Nauruz 1 from Kazakhstan.

Cultivars Kharkivska 37, Kharkivska 23, Elan, Krasnokoutka 10, and Bezentchoukskaya 182 are the descendants of Kharkivska 46, from which they derived their resistance to fruit fly injury.