ITEMS FROM CROATIA

Bc Institutes for Breeding and Production of Field Crops and

Plant Protection

Marulicev trg 5, HR-41000, Zagreb, Croatia.

The meaning of the Bc Institute for Breeding and Production of Field Crops - Zagreb, to wheat production in the Republic of Croatia.

S. Tomasovic, P. Javor, and B. Sesar.

Wheat breeding in Croatia began soon after the first attempts at using Mendelian rules (genetics) in the world of plant breeding. It was in the very beginning of this century. The first document, entitled `Crossing wheats squarehead x Banatska brkulja' was published in `Gospodarska smotra' by Prof. Gustav Bohutinsky in the year 1911.

The highest yielding variety, between two world wars, was the domestic variety, U1 (Osjecka sisulja), created by Prof. Mirko Koric. U1 was the leading variety until the use of Italian wheat varieties in our program. The new structure of the wheat plant of the Italian varieties and a new strategy in wheat production, in which higher yield is based on more plants per square unit plot, had an influence on wheat breeding throughout the world, as well as in Croatia. The new fashion of the Italian wheat variety was first accepted Dr. Josip Potocanac in Zagreb.

Dr. Potocanac tried to improve through breeding the inadequate winterhardiness and susceptibility to stem rust (Puccinia graminis f.sp. tritici) that, in some years, cause disasters in production of the Italian varieties. Combining the traits of Italian and American varieties, he created two famous wheat varieties, Zlatna dolina and Sanja, which were released in 1971.

Zlatna dolina received international appreciation and, in local wheat production, overcame the Italian varieties, because it yielded about 15 % higher than the leading variety, Libellula (Martinic-Jercic 1990). At the Bc Institute for Breeding and Production of Field Crops, 54 varieties of winter wheat were created (see Table 1).

After Zlatna dolina and Sanja, the varieties produced by the Bc Institute - Zagreb dominated over 70 % of the wheat fields of Croatia in 1984 and 50 % today. From the appearance of Zlatna dolina, wheat production in Croatia continually increased, owing to domestic varieties and the improvement of technology that enabled better utilization of its genetic potential (Fig. 1). Zlatna dolina, Sanja, Super zlatna, Baranjka, Lonja, Zagrepcanka, Adriana, and Korona were recognized in foreign countries (Potocanac and Javor; Javor; Tomasovic). For better stability and preservation of nature, we incorporated genetic resistance to the main fungal wheat diseases (stem rust, powdery mildew, Septoria spp., and Fusarium spp.). Their common characteristics are high yield potential, considerably above 10 t/ha; adaptability; and remarkable yield stability in production.

Line Zg 4160/91 produced 10,720 kg/ha, which is 91.73 % (886 kg) above the standard variety, Sana (Fig. 2). The relationships between yield and kernel and flour quality of the newest lines are markedly improved (See Tables 2 and 3). The percentage of total proteins increased in the new lines, as well as the elevation of sedimentation values.

New varieties, and especially the latest lines, distinguish themselves by their good farinological characters, for bread making quality, and a high capacity for water absorption. The achieved water absorption capacity is similar to that of most good bread-quality wheats. Increase in 1,000-kernel weight is markedly expressed relative to earlier varieties. The latest lines realized increased production per spike owing to incorporation of the Rm, Ts, and Nr genes. The new lines have improved stalk strength, making them very resistant to lodging.

Table 3. Quality values of the new winter wheat varieties of the Institute for Plant Breeding and Crop Production - Zagreb.

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Variety % of Value Quality Water Quality Quality Extension Resistance Ratio

protein (ml) class absorption % number group group (O/R)

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Darka 12.9 34.7 II 57.0 58.5 B1 166 230 1.38

Davorka 13.3 30.8 II 50.8 53.9 B2 187 355 1.89

Melita 12.4 33.8 II 55.5 55.1 B1 171 190 1.11

Olga 11.5 43.0 I-II 59.3 65.0 B1 147 245 1.32

Rina 12.0 38.0 II 50.0 35.4 C1 116 340 2.93

Rugvica 11.6 22.9 III 52.0 50.6 B2 116 340 2.93

Sandra 14.0 47.8 I 57.7 67.3 B1 139 215 1.54

Sutla 12.2 31.8 II 52.0 47.4 B2 129 470 3.64

Tina 13.8 64.4 I 53.8 63.8 B1 180 320 1.78

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Effective Sr and Pm resistance genes of wheat in Croatia.

Bogdan Koric.

In order to obtain cultivars with satisfactory resistance to disease, it is necessary to investigate the relationship between the cause of the disease and the resistance gene, thus, finding the real source of resistance. This is the approach we took at the Bc Institute for Breeding and Production of Field Crops in Zagreb in breeding domestic wheat cultivars by selection. The investigations began by testing the efficiency of Sr genes to resist stem rust infections. In 1968, the investigations were extended to finding efficient Pm resistance genes to the powdery mildew fungus.

The results of the investigations, from 1990 to 1994, showed varying percentages of efficiency of the Pm genes. Analyzing the genealogy of the newly recognized cultivars in 1993 and 1994, we can see that they do not contain any of the efficient Pm resistance genes (Table 1). The same applies to the Sr genes, where there is disagreement between efficient Sr genes and those incorporated into the genefundus by selection (Table 2).

Table 1. Efficiency of powdery mildew resistance genes from 1990-1994.

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Efficiency of Pm genes (% per year)

Resistance gene 1990 1991 1992 1993 1994

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Pm3b 45 46 78 59 30

Pm4b 84 69 66 57 63

Pm9 73 68 83 88 96

Pm2 + Mld - - 98 76 85

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Table 2. Efficiency of stem rust resistance genes.

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Resistance

gene Efficiency of Sr gene (%)

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Sr7a 99

Sr14 98

Sr11 82

Sr9e 78

Sr36 60

Sr21 50

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ITEMS FROM THE CZECH REPUBLIC

Research Institute for Crop Production, Prague - Ruzyne

Drnovski 507, CZ-161 06 Praha 6, Ruzyne, Czech Republic.

Evaluation of Czech and Slovak wheat land races and old cultivars from a quality point of view.

Z. Stehno, L. Dotlacil, and M. Manev.

The total volume of the Czech wheat genetic resources collection reached 9,234 accessions by the end of 1994. Among them, 672 accessions of Czech and Slovak origin have been included. Historically, the original Czech and Slovak wheat land races and old cultivars were gathered up at the end of the Second World War by small breeding and research stations. In the early 1950s, they were transmitted to the Research Institute for Crop Production in Prague-Ruzyne.

One set of these land races and old cultivars was examined in 1994 for their grain quality characters. Crude protein content, wet gluten content, gluten index (GI), and quick microsedimentation in sodium dodecyl sulphide (SDS) have been evaluated. Three contemporary wheats `Sparta', `Samanta', and `Ilona' have been used as check cultivars. Two of them, Samanta and Ilona, are classified in the `List of released cultivars' as very good from a bread making quality point of view. Sparta has a low baking quality.

Under a relatively dry and warm growing period in 1994, the land races and old cultivars exceeded check cultivars in crude protein content, wet gluten content, and sedimentation (SDS) value. Among land races and old wheats, Vouska z Tremosnice has had the highest crude protein content (16.63 %) and, simultaneously, a high wet gluten content (37.5 %). A very high protein content (16.52 %) and the highest wet gluten content have been measured simultaneously in Slovenska B.

Differences between check cultivars having high baking quality, Samanta and Ilona, and the low quality of Sparta have been confirmed by the results of the sedimentation microtest. In this parameter, the best results have been reached by Ceska presivka (8.1 ml) and Rokycanska sametka (7.6 ml).

For evaluation of gluten quality, the gluten index (GI) parameter has been used. Large differences are obvious between the check cultivars on one side and land races and old varieties on the opposite side. Only Slovenska 777 has a relatively high GI.

From the results of these preliminary experiments, we can conclude that Czech and Slovak land races and old cultivars could be good donors of crude protein content and wet gluten content, but their gluten quality (measured by GI) was low.

Table 1. Quality characters in Czech and Slovak land races and old cultivars of wheat.

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Crude protein SDS test Wet gluten

Land race/cultivar content (%) (ml) content (g/100g) GI (%)

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Check cultivars.

Sparta 13.28 4.70 22.50 87.00

Samanta 13.07 6.50 23.10 99.00

Ilona 13.24 6.30 23.30 99.00

Mean 13.20 5.83 22.97 95.00

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Czech and Slovak land races and old wheat cultivars.

Kostomlatska Sametka 14.81 6.50 34.00 72.00

Rokycanska Sametka 15.18 7.60 35.30 68.00

Vouska z Tremosnice 16.63 5.60 37.50 21.00

Bila od Dukovan 16.11 7.00 34.20 50.00

Hanacka Belka 16.19 6.50 39.40 36.00

Dobrovicka 10 15.32 6.20 35.70 35.00

Chlumecka 12 15.86 7.30 39.10 52.00

Ceska Presivka 15.29 8.10 37.20 59.00

Ruska Genealog. Belka 14.63 6.30 34.20 47.00

Pyselka 15.38 5.70 37.40 42.00

Zidlochov. Jubilej. Osinata 14.97 6.50 35.40 34.00

Slovenska B 16.52 6.80 41.90 45.00

Slovenska 777 15.84 8.30 35.50 91.00

Slovenska 2 16.50 5.50 38.30 34.00

Trebisovska 76 15.97 5.50 39.50 43.00

Viglasska Eervenoklasa 16.04 7.50 38.10 57.00

Mean 15.70 6.68 37.04 49.13

Standard deviation 0.63 0.90 2.28 17.38

Variance 0.40 0.80 5.19 302.12

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Earliness and photoperiodic response of some wheat cultivars in the Czech Republic.

J. Kosner and D. Zurkova.

Continuing the experiments of 1991, 1992 (Kosner and Bromova 1993), and 1993 (Kosner 1994), we observed earliness and the photoperiodic response of another collection of wheat varieties in 1994. This collection contained mostly newly-listed winter and spring varieties and new lines from the Czech Republic. The control varieties Sonora, photoperiod insensitive, with dominant alleles Ppd1 and Ppd2, and Zdar, photoperiod sensitive, were the same as in the former experiments.

As in the former experiments, all seeds of winter and spring wheat were vernalized for 8 weeks under 1-3FONT SIZE=2 FACE="WP MultinationalA Roman"/C and planted on 20th April (in 50FONT SIZE=2 FACE="WP MultinationalA Roman"/N longitude, a day length greater than 14 hours begins on this day) on a plot darkened (by automatic device) or nondarkened. The 10-hour day period was from 8 a.m. to 6 p.m. The period from the planting of vernalized plants to heading was scored.

The period from the planting of vernalized plants to heading, under a natural long-day (light period longer then 14 hours), was considered as the basic trait of earliness. Photoperiodic response was characterized by prolonging the period to heading by means of shortening the light period to 10 hours (the difference between the number of days to heading under a naturally long day and short day). Table 2 shows the results.

The dependence of earliness on photoperiodic response also was evaluated.

Table 2. The mean number of days to heading, under long and short days and the

difference in number of days caused by the change of day length.

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Days from planting to heading Prolongation

--------- -------------------------------------- of period to

Variety Growth Long day Short day heading

type (Basic (Photoperiod

earliness) sensitivity)

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Sonora spring 54.22 70.30 16.08

ST-127 spring 56.44 96.80 40.36

ST-125 spring 57.65 99.57 41.92

Aura winter 58.89 82.08 23.19

Bruta winter 60.33 77.18 16.84

Samanta winter 61.22 79.87 18.64

UH-7035 spring 61.67 104.92 43.25

Barbara winter 63.13 79.00 15.88

Sida winter 64.06 85.36 21.30

Zdar winter 65.54 112.00 46.46

Asta winter 66.17 110.00 43.83

Siria winter 66.28 111.80 45.52

Trane winter 68.33 129.20 60.87

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References.

Kosner J and Bromova P. 1993. Photoperiodic sensitivity of cultivars of the Czechoslovak wheat assortment. Ann Wheat Newslet 39:142-143.

Kosner J. 1994. Photoperiodic sensitivity of the wheat cultivars. Ann Wheat Newslet 40:97-98.

Disease resistance of wheat cultivars registered in the Czech Republic in 1994.

P. Bartos, R. Hanusova, and E. Stuchlikova.

In 1994, three advanced lines bred by the plant breeding company Selgen, one advanced line produced by the company Morstar, one advanced line from the Slovak plant breeding station at Solary, and the German cultivar Trane were registered in the Czech Republic.

Cv. Siria has good field resistance to leaf rust and powdery mildew. It possesses Pm4b and, very likely, also Pm2 and Pm6. The specific powdery mildew and leaf resistance genes seem to be derived from cv. Maris Marksman, one of its parental cultivars. Cv. Siria has field resistance to yellow rust, but it is susceptible to stem rust.

Cv. Mona possesses the 1BL-1RS translocation, hence, resistance genes Lr26, Yr9, Sr31, Pm8, and also Lr3. In the field, it has medium-resistance even to yellow rust races overcoming Yr9.

Cv. Asta is highly resistant to yellow rust. It also shows good powdery mildew resistance, having Pm2 and Pm6 derived from Maris Marksman, one of its parental cultivars. It also possesses Lr3 derived from its other parental cultivar, Akhtyrchanka. In the field, it is rarely effective, because leaf rust races virulent to Lr3 prevail in the Czech Republic. Cv. Asta possesses a gene for medium stem rust resistance.

Cv. Bruta shows above-average resistance to leaf rust in the field and medium resistance to yellow and stem rusts and powdery mildew.

Cv. Rexia has above-average resistance to leaf rust and powdery mildew, and medium resistance to stem and yellow rusts. The presence of Lr3 and Sr5 is probable.

Cv. Trane carries the 1BL-1RS translocation and differs from the cultivar Mona, which has the same translocation, by possessing higher resistance to powdery mildew and yellow rust to races virulent to Yr9.