ITEMS FROM BRAZIL

NATIONAL RESEARCH CENTER FOR WHEAT - EMBRAPA

Centro Nacional de Pesquisa de Trigo, BR 285, Km 174, Caixa Postal 569, 99001-970, Passo Fundo, Rio Grande do Sul, Brazil.

Wheat cultivars in Brazil.

C.N.A. de Sousa, E.P. Gomes, J.C.S. Moreira, L. de J.A. Del Duca, and P.L. Scheeren.

Wheat cultivars from 1922 to 1997. Wheat breeding in Brazil began in 1919, and several organizations are involved. The number of wheat cultivars under commercial cultivation from 1922 to 1997 was 365. Only three cultivars belong to the species T. turgidum var. durum. The remaining cultivars are the species T. aestivum. Ninety-three wheat cultivars were under recommendation in Brazil in 1997. Seven of these cultivars have been recommended for more than 19 years: IAC 18-Xavantes, Jupateco 73, Peladinho, IAC 13-Lorena, INIA 66, IAC 5-Maring, and BH 1146. Two hundred and sixty-seven cultivars were obtained through artificial crosses with selections made in Brazil, and 65 were derived from introductions, most of them from Mexico.

New wheat cultivars from Embrapa Trigo. Embrapa 119 and Embrapa 120, both obtained from lines produced in Passo Fundo, RS, were released in 1997.

Embrapa 119. Embrapa 119 was selected from the double cross 'PF 82252 / BR 35 // IAPAR 17 / PF 8550', made in Passo Fundo in 1986. Plant selection was done in Passo Fundo in the F2, F4, F5, and F7 generations, and a bulk harvest was made in Braslia (summer generations) in F3 and F6. The line was bulked in the F8 in 1991. After 5 years of yield tests, the line was released for cultivation in RS in 1997. The cultivar 119 yielded 2,722 kg/ha, 102.1 % in relation to Embrapa 16, the leading cultivar in RS, according to the average of 48 trials conducted in several locations in RS from 1994 to 1996. Embrapa 119 is an early, mid-tall spring wheat. This cultivar is moderately susceptible to powdery mildew, resistant to leaf and stem rusts, and moderately resistant to glume blotch and to aluminum toxicity. Embrapa 119 is a strong wheat in relation to industrial quality, and it has the high molecular weight glutenin subunits 2* 7+8 5+10.

Embrapa 120. Embrapa 120 was selected from the cross 'PF 83899 / PF 813 // F27141', made in Passo Fundo in 1987. F27141 is the number of the cross 'PF 83743 /5/ PF 83182 /4/ CNT 10*4 // Lagoa Vermelha*5 / Agatha /3/ Londrina*4 / Agent // Londrina*3 / Nyu Bay' related to a segregating material in F6. The pedigree method was used with plant selection in Passo Fundo and a summer multiplication in Braslia. The line was bulked in the F6 in 1991. After 5 years of yield trials, the line was released for cultivation in RS in 1997. Embrapa 120 is an outstanding cultivar for grain yield. The cultivar yielded 2,877 kg/ha, according to 48 trials established in several locations in RS from 1994 to 1996, with a mean of 107.9 % in relation to Embrapa 16, the leading cultivar in RS. Embrapa 120 is an early, mid-tall spring wheat. This cultivar is susceptible to powdery mildew in greenhouse tests, but presents good field reaction up to now; moderately susceptible to leaf rust; resistant to stem rust; and moderately susceptible to glume blotch. Embrapa 120 is a mid-strong wheat for industrial quality, and the flour is good for bread and for home use. The high molecular weight glutenin subunits of Embrapa 120 are 2*, 7+9, and 5+10.

Results of sprouting resistance.

C.N.A. de Sousa.

Preharvest sprouting can be a problem for wheat in southern Brazil in some years, because of excess of rain and other weather conditions. The cultivar Frontana, released in 1940, is an important source of resistance and a well-adapted cultivar for Brazilian wheat areas. However, such resistance is not present in some cultivars like Embrapa 16 and CEP 24-Industrial, at present the two main cultivars in the state of Rio Grande do Sul.

A survey was done in Passo Fundo, RS, in order to know the behavior of the 251 wheat cultivars from the crossing block of Embrapa Trigo in 1996 sown at five different times in the field. Sprouting was a severe problem in some regions in RS in 1996 but not in Passo Fundo.

Samples of 200 spikes were taken from the field plots, out of which 100 spikes were immersed in water for 2 hours, kept in a moist chamber for 48 hours, and then dried. The spikes were threshed, and the grain was used for the wet falling number test (FN-wet), according to Hagberg's method. The remaining 100 spikes were threshed and used for the dry falling number test (FN-dry). The plots for the last sowing date in the crossing block, with most of the plots ready to be harvested in November, were left in the field waiting for a heavy rain. A rain of 39.3 mm occurred on 11 and 12 December, and afterwards the plots were harvested and the rain falling number (FN-rain) was determined. The general results obtained are listed in Table 1.

Frontana had a falling number of 128 (wet), 294 (rain), and 391 (dry). The most resistant cultivars, according to the FN-wet and the FN-rain data, with an average of more than 300 and a minimum value of 200 were: CEP 27, Coker 762, Embrapa 40, FB 4200, FL 72185-A-A2-C1, Florida 301, General Vargas, GW 3, GW 4, Hulha Negra, IAPAR 53, IPF 64736, IPF 64758, IPF 64762, Jesuta, Karim, Neepawa, ND 603, OR 1, Patriarca-V, PF 88522, PF 88649, PF 89375, PF 90132, PF 90134, PF 9219, PF 9234, PF 92231, PF 92342, PF 92482, PF 932005, PF 940042, PF 940077, PF 940086, PF 940151, PF 950318, PF 950320, PG 1, Pitana, Pro Inta Federal, Rascon, RL 6082, RL 6114, RS 8, SA 9340, SA 9458, Toropi, and Trigo BR 27. Neepawa and Pitana were the only cultivars with FN averages of more than 400 under both conditions.

The most susceptible cultivars according to the tests (wet and rain), with an FN minimum value of less than 100 in both tests, were: Anahuac 75, CEP 24, CT 615, Embrapa 16, Embrapa 52, IAPAR 29, IDS 934-21, Klein Cartucho, ND 507-A, OCEPAR 11, Pato Blanco, PF 85757, PF 86257, PF 87301, PF 87770, PF 88711, PF 92334, Pro Inta Isla Verde, Trigo BR 26, and Trigo BR 42.

1997 wheat cultivar yield trials in Passo Fundo, state of Rio Grande do Sul, Brazil.

J.C.S. Moreira and C.N.A. de Sousa.

The National Research Center for Wheat, a unit of Embrapa in Passo Fundo, Brazil, conducted 27 yield trials testing about 570 common wheat cultivars.

The climatic conditions during the wheat cycle in Passo Fundo (June-November) included below-normal precipitation in June and July. An excess of rain occurred in August, October, and November, with 804 mm of precipitation from 29 September to 13 November, which means that about half of the annual precipitation was received in 45 days. The high moisture favored the occurrence of diseases and contributed to a decrease in yield compared to last year. An average yield of 1,100 kg/ha was estimated for RS, a reduction of 40 % compared to 1996.

The trials were conducted in a rotation area. The check cultivars used in 1997 were the same as those in 1996: BR 23, CEP 24, and EMBRAPA 16. The latter is the main cultivar in Rio Grande do Sul and is sown to about 320,000 ha (66 %) of the growing area in this state. Cultivars with higher yields than the best check are listed in Table 2.

Agronomic, baking, and plant health characteristics of wheat cultivars and lines of the Paraná State Yield Trials, 1997.

L.J.A. Del Duca, C.N.A. Sousa, and E.M. Guarienti.

Paraná is the most important state for wheat production in Brazil. A nursery including 85 cultivars and lines tested in intermediate and final trials in Paraná (PR) in 1997 was evaluated under field conditions at the Centro Nacional de Pesquisa de Trigo (National Research Center for Wheat), Passo Fundo, RS. Information regarding complex diseases on the spike and powdery mildew was obtained under field conditions with natural infection (planting 13 June, 1997). The scale ranged from 0 (immune or without symptoms) to 5 (highly susceptible). For kernel quality, the scale ranged from 1 (excellent) to 5 (very poor). In addition to grain plumpness, a severe scab infection was of fundamental importance in the ratings.

A nursery to evaluate effects of aluminum was planted in 1997 in an acid soil with a high aluminum level. The index of susceptibility (IS) varied from 0.50 (highly resistant) to 5.00 (highly susceptible). Information on baking quality from the alveograph method (W = deformation energy of dough) at EMBRAPA-CNPT and EMBRAPA-CTAA obtained between 1990-97 is presented. The data represent the averages from different numbers of years for each genotype.

The listed wheats were outstanding for the following characteristics:

Complex disease on spike (score of 1 to 1+): CEP 24, Iapar 29, OC 9716, OR 1, ORL 9285, ORL 9361, ORL 93320, ORL 93449, ORL 93762, PF 9099, PF 93167, PF 93188, WT 95037, WT 95041, and WT 95068.

PM (rating between 0 and 2+): Embrapa 16, Embrapa 27, Embrapa 49, Embrapa 120, OC 979, ORL 9285, ORL 9361, ORL 93320, ORL 93762, PF 9099, PF 9293, PF 93167, PF 93188, WT 95004, WT 95007, WT 95032, WT 95037, WT 95040, WT 95042, WT 95043, WT 95068, and WT 95069.

Kernel quality (rating 2): ORL 9285, ORL 9361, ORL 93320, PF 9099, and PF 93188.

Aluminum tolerance (IS = < 1.26): EMBRAPA 49, IAPAR 53, IAC 5, OC 9711, OC 9712, OCEPAR 21, Trigo BR 35, and WT 95004.

W (score 200): Anahuac 75, CEP 24, Coodetec 101, Embrapa 16, Embrapa 49, IAC 5, Iapar 6, Iapar 17, Iapar 28, Iapar 29, Iapar 53, Iapar 78, IOR 90226, IWT 9430, LD 941, Manitoba 97, 0C 965, 0C 9511, Ocepar 16, Ocepar 21, Ocepar 22, Ocepar 23, OR 1, ORL 9285, ORL 93320, PF 9099, PF 91205, PF 93167, PF 93188, PG 9337, PR 961, TRIGO BR 18, WT 95004, WT 95007, WT 95032, WT 95037, WT 95040, WT 95041, WT 95042, WT 95043, WT 95068, and WT 95069.

The data should be interpreted as preliminary results considering that most of the information refers to only 1 year of evaluations.

Testing wheats for dual-purpose in the Guarapuava region.

L.J.A. Del Duca and I. Sandini.

Discussion regarding the potential of wheat prodution in the Guarapuava Region of Brazil (the southcentral part of the state of Paraná) was published previously in AWN 41:62 (1995).