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NATIONAL RESEARCH CENTER FOR WHEAT - EMBRAPA

Centro Nacional de Pesquisa de Trigo, BR 285, Km 174, Caixa Postal 451, 99001-970, Passo Fundo, Rio Grande do Sul, Brazil.

Wheat Brs 176: a new option for the southcentral area of the state of Paraná.

Leo de J.A. Del Duca, Aroldo G. Linhares, Cantídio N.A. de Sousa, Eliana M. Guarienti, João Carlos S. Moreira, Márcio S. Silva, Pedro L. Scheeren, Itacir Sandini, Celso Wobeto, and Rudimar Molin.

After 5 years of trials with clippings simulating animal grazing, in a partnership with the Fundação Agrária de Pesquisa Agropecuária (FAPA) and Fundação ABC, the wheat cultivar BRS 176 was indicated for cultivation in early sowing for grain production in the region 8 of Paraná State (PR). At Guarapuava and Carambeí (PR), with early sowing time for forage and grain production during the 1994-98 period, BRS 176 wheat had dry matter yields 24 % and 18 % higher with one clipping (1C) and two clippings (2C), respectively, than that of the check (common black oat), which yielded 1,187 kg/ha (1C) and 2,124 kg/ha (2C). BRS 176 grain yields for the treatment without clipping (WC), 1C, and 2C, were 16 %, 37 %, and 128 % greater, respectively. The average yields of the three early wheat checks, cultivars Embrapa 16, Trigo BR 23, and CEP 24 Industrial were 2,966 kg/ha (WC), 2,535 kg/ha (1C), and 922 kg/ha (2C). The average grain yield of the early wheats without clippings was 2,966 kg/ha, the normal condition of crops, whereas BRS 176 had average yields of 3,451 kg/ha grain (WC), 3,483 kg/ha of grain + 1,470 kg/ha of dry matter (1C), and 2,104 kg/ha of grain + 2,506 kg/ha of dry matter (2C).

BRS 176 was obtained as a secondary outcome of an experiment comparing selection methods, using the modified mass method, from the cross 'Hulha Negra / CNT 7 //Amigo / CNT 7'. BRS 176 has a late cycle for the conditions of the Paraná State, intermediate vegetative habit, medium plant height (100 cm in Guarapuava), erect flag leaf, haired and fusiform spikes, and grains with soft texture. The new cultivar is moderately susceptible to lodging, resistant to shattering, and moderately resistant to sprouting and aluminum soil conditions. At the seedling stage, it showed susceptibility or ununiformity to leaf rust under controlled conditions and intermediate susceptibility under field conditions. The cultivar is resistant to stem rust and susceptible to mildew under controlled conditions, but moderately resistant in the field. BRS 176 is moderately susceptible to glume blotch and scab, susceptible to the BYDV, and moderately resistant to WSBMV.

Wheat breeding for early sowing and use in double-purpose production.

Leo J.A. Del Duca, Ana C.A. Zanatta, Cantídio N.A. Sousa, Edson J. Iorczeski, Eliana M. Guarienti, Gilberto R. Cunha, Leila M. Costamilan, Márcio S. Silva, Martha Z. Miranda, Osmar Rodrigues, Pedro L. Scheeren, and Sandra P. Brammer.

The genetic improvement for adaptation to early sowing and use in double-purpose production seeks to develop wheat for the southern Brazilian region, aiming for sustainability of the agroecosystems regarding reduction of soil losses, needs for permanent green cover and winter alternatives in no-tillage systems, reductions of risks and costs, diversification of income, and activities integrating crop-cattle production. Results obtained with early sowing and for double-purpose production with BRS 176 and PF 87451 wheat genotypes in Rio Grande do Sul (RS), demonstrated the viability and the potential of such handling and diversification alternatives for the wheat crop (Tables 1 and 2). Yield advantages compared to the average of the early wheats and the black oat are shown. The use in double-purpose production could add sustainability and flexibility, because anticipated income from beef cattle, milk, or wool would not be dependent on climatic and market oscillations, even during the cycle of the crop, it also could be the most profitable activity, depending on the economic projections of the year.

For the Brazilian commercialization standard, BRS 176 is classified as soft wheat, indicated for cookies, confectionery, pizzas, and use with hard wheat for bread making and/or domestic use.

Hybridizations are made with winter and facultative wheats to lenghten the cycle and photoperiodic requirement up to flowering. Originating populations were selected by the genealogical and bulk methods or by a combination of both. Haplodiploidization activities also took place, through crossings with corn, to accelerate the selection of new lines. Selection activities in early sowing involved: a) preselection and final selection for cycle, diseases, and agronomic type; b) grazing of areas with segregants selected for double-purpose production; c) grain selection in the selected plants; and d) conduction of trials for grain yield and double-purpose production, with agronomic evaluations and quality tests for the different uses.

Agronomic, baking, and plant health characteristics of wheat cultivars and lines of the Paraná State Yield Trials, 1998.

L.J.A. Del Duca, E.M. Guarienti, L.M. Costamilan, M.S. Silva, M.Z. Miranda, and P.L. Scheeren.

Paraná is the most important wheat-producing state in Brazil. A nursery including 85 cultivars and lines tested in intermediate and final trials in Paraná state (PR) in 1998 was evaluated on field conditions at Embrapa, the National Wheat Research Center (Centro Nacional de Pesquisa de Trigo), Passo Fundo, RS. Information regarding complex diseases on the spike and powdery mildew was obtained in field conditions with natural infection (planting 6 June, 1998). The scale ranged from 0 (immune or without symptoms) to 5 (highly susceptible). For kernel note, the scale ranged from 1 (excellent) to 5 (very poor) and, besides grain plumpness, a severe scab infection was of fundamental importance in the graduation. Information on baking quality from the alveograph method (W = deformation energy of dough) at Embrapa, the National Wheat Research Center laboratory done from 1990-98 is shown. The data represent averages from different numbers of years for each genotype.

The genotypes below had the best performance for the following characteristics:

Complex diseases on spike (1 to 2) = CEP 24, CIT 96100, COODETEC 101, COODETEC 103, FUNDACEP 29, IA 963, IA 981, LD 941, OC 963, OC 965, OC 983, PF 9293, WT 95040, and WT 95041.

Powdery mildew (0 to 2+) = Because of the low levels registered to this disease, only IAPAR 17, IAPAR 28, IAPAR 29,
LD 974, OC 983, OC 984, WT 95032, and WT 95037, were rated 3 or more.

Kernel note (> 2) = CEP 24, FUNDACEP 29, CEP 9313, CIT 96100, COODETEC 101, COODETEC 103, IA
981, IAPAR 17, IAPAR 53, IAPAR 84, LD 969, LD 975, OCEPAR 21, OC 976, OC 983, OC 9810, OC 9814, PF 9293, PF 93167, PF 93175, PF 93218, WT 95032, WT 95037, WT 95040, WT 96061, WT 96168, Trigo BR 23, and Trigo BR 35.

W (> 200) = ANAHUAC 75, CEP 24, COODETEC 101, COODETEC 102, COODETEC 103, Embrapa
16, Embrapa 49, FUNDACEP 29, IAPAR 6, IAPAR 17, IAPAR 28, IAPAR 29, IAPAR 53, IAPAR 78, IAPAR 84, IWT 9430, IWT 95003, LD 941, 0C 965, OCEPAR 16, OCEPAR 21, OCEPAR 22, PF 9293, PF 93175, PF 940384, TRIGO BR 18, WT 95032, WT 95037, WT 95040, WT 95041, WT 95043, WT 95068, WT 96061, WT 96063, WT 96085, WT 96089, WT 96104, WT 96111, WT 96120, and WT 96168.

Data should be interpreted as preliminary results considering that most of the information was from 1 year of evaluation.

New wheat cultivars from Embrapa Trigo.

Cantídio N.A. de Sousa, João C.S. Moreira, Leo de J.A. Del Duca, Márcio Só e Silva, and Pedro L. Scheeren.

The Brazilian Agricultural Research Corporation (Embrapa) is developing wheat breeding programs in Passo Fundo (RS), Pelotas (RS), Londrina (PR), Dourados (MS), Goiânia (GO), and Planaltina (DF). The National Wheat Research Center (Embrapa Trigo) is located in Passo Fundo, RS. The acronym 'Embrapa' that was part of the name of the cultivars released by its research centers was replaced by 'BRS' in 1998, because of registration and protection requirements. For this reason, the name Embrapa 49, released in 1996, was changed to BRS 49, Embrapa 119 to BRS 119, and Embrapa 120 to BRS 120.

Five lines selected in Passo Fundo from crosses made by Embrapa Trigo were released for recommendation in Brazil in the 1997-99 period. They are the cultivars BRS 119, BRS 120, BRS 176, BRS 177, and BRS 179. Information on year of release, line name, cross, and states where these cultivars were recommended is in Table 3.

All mid-tall cultivars, BRS 119 is the shortest. They are moderately resistant to aluminum toxicity in the soil and resistant to stem rust. BRS 119, BRS 120, and BRS 179 have an early cycle, whereas BRS 176 and BRS 177 have an internediate cycle. BRS 177 and BRS 179 showed good resistance to scab. BRS 176 is resistant to WSBMV, BRS 177 is resistant to tan spot, and BRS 179 has good resistance to leaf rust. BRS 120 and BRS 177 have good resistance to preharvest sprouting. BRS 119 is the best cultivar recommended for RS in relation to bread-making quality. BRS 176 is recommended for early sowing. BRS 120 and BRS 177 came from the same cross; however, BRS 177 has a longer cycle and it is more resistant to leaf rust than BRS 120.

Evaluation of leaf-tip necrosis in Brazilian wheat genotypes.

Cantídio N.A. de Sousa and Amarilis L. Barcellos.

The gene Ltn for leaf tip necrosis is a phenotypic marker associated with the gene Lr34 for resistance to leaf rust. Wheat genotypes have been tested in the greenhouse and under field conditions in Passo Fundo, RS, Brazil, for leaf tip necrosis as found in the old Brazilian wheat cultivar Frontana, cited several times in the literature for Lr34 and Ltn. Leaf-tip necrosis is not an easy test because of mixed symptoms of fungus diseases, virus diseases, wind, and cold damage on leaves. Two hundred seventy-four genotypes were tested for more than 1 year during the period from 1993 to 1999. Leaf tip necrosis was observed with consistency in 24 Brazilian genotypes, for which the presence of the gene Lr34 is postulated. The cross and the probable source of the genes Ltn and Lr34 are presented (Table 4).

The gene Lr34 seems to contribute to the long-term cultivation of some Brazilian cultivars, such as BH 1146, IAC 5, Frontana, and Trigo BR 23.

Leaf tip necrosis was not found with consistency in 73 Brazilian genotypes including the cultivars BRS 49, BRS 119, BRS 120, BRS 176, BRS 177, CEP 14, CEP 17, CNT 8, CNT 10, Embrapa 15, Embrapa 16, Embrapa 21, Embrapa 27, Embrapa 41, Embrapa 52, Iapar 53, Ocepar 22, Toropi, Trigo BR 24, Trigo BR 32, Trigo BR 37, Trigo BR 42, and Trigo BR 43.

1999 Wheat Cultivar Yield Trials in Passo Fundo, State of Rio Grande do Sul (RS), Brazil.

João C.S. Moreira and Cantídio N.A. de Sousa.

Forty-five yield trials testing about 874 spring genotypes of bread wheat were conducted at the National Wheat Research Center, of Embrapa, in Passo Fundo, RS, Brazil (Table 5). Climatic conditions during the wheat season in Passo Fundo (June to November) were good. A long period of drought occurred in July and August producing plants of less stature than normal. However, below-normal rainfall and air moisture in October and November resulted in good conditions during the reproductive stage up to harvesting time. An excess of rainfall is the main constraint for wheat grain production in southern Brazil. Experimental plots yielded more than 5,000 kg/ha in some regions. An average yield of 1,600 kg/ha was obtained in 1998, and 1,800 kg/ha are estimated for the state of Rio Grande do Sul in 1999, which is an increase of 12 % relative to 1998.

The trials were conducted in a crop-rotation area. The check cultivars used in 1998 and 1999 were BR 23, CEP 24, and CEP 27. The last cultivar was the leading one in the wheat area in Rio Grande do Sul in 1999 (95,200 ha), followed by BR 23 and Fundacep 29 with 56,000 and 45,600 ha, respectively.

Cultivars and lines that yielded 5 % or more than the check BR 23 in Passo Fundo according to the trial are given in Table 5.