Wheat cultivars recommended in Brazil.
C.N.A. de Sousa, E.P. Gomes, I. Ambrosi, J.C.S. Moreira, L. de J.A. Del Duca, and P.L. Scheeren.
Wheat breeding in Brazil started in
1919 with the work in Alfredo Chaves (Veranopolis, Rio Grande
do Sul), and in Ponta Grossa, Parana. Three hundred and twenty
eight wheat cultivars were on cultivation/recommendation over
the period from 1922 to 1992. Three cultivars (EMBRAPA 21, EMBRAPA
22, and EMBRAPA 24) were released in 1993, and two cultivars (OCEPAR
22 and EMBRAPA 27) were released in 1994. The wheat area was
confined mainly to southern Brazil (Rio Grande do Sul, Santa Catarina,
and the southern Parana region) before the 1970s. The wheat area
expanded to other regions in the states of Parana, Mato Grosso
do Sul, and Sao Paulo in the 1970s. Parana became the main state
for wheat cropping in Brazil in 1977. Wheat is also grown in
the states of Minas Gerais, Goias, and Mato Grosso, as well as
in the Distrito Federal, but at a smaller scale. The number of
wheat cultivars recommended for Brazil in 1994 was 92. Trigo
BR 23 was the main cultivar grown in Brazil in 1994 with an estimated
area of 458,000 hectares. Trigo BR 35 was the second cultivar
in acreage in the states of Rio Grande do Sul, Santa Catarina,
and Parana in 1994.
The wheat areas in Brazil, the number of wheat cultivars in recommendation in 1994, and the main cultivar according to the state are presented in the following table.
_______________________________________________________________________________
Maximum area2 1993 area 3 1994 area 4 Number of Main
State1 ha/year ha ha cultivars cultivar
(1994)
_______________________________________________________________________________
RS 2,184,899/1979 531,000 509,800 19 T. BR 23
SC 125,568/1987 61,000 61,000 13 T. BR 23
PR 1,942,381/1986 930,000 720,000 41 T. BR 23
MS 426,649/1987 69,300 50,600 26 T. BR 17
SP 219,300/1989 43,100 34,900 18 IAC 60
MG 24,734/1982 4,000 5,600 12 T. BR 26
GO 3,500/1993 3,500 3,500 12 T. BR 33
DF
_______________________________________________________________________________
Total 4,104,144/1979 1,641,900 1,385,400
_______________________________________________________________________________
1 Federation units: Rio Grande do Sul (RS), Santa Catarina (SC), Parana (PR), Mato Grosso do Sul (MS),
Sao Paulo (SP), Minas Gerais (MG), Goias (GO), and Distrito Federal (DF).
2 Source: BB/CTRIN and CONAB/DIPLA/DEPOS.
3 Source: CONAB/DIPLA/DEPOS.
4
Estimate: CONAB/DIPLA/DEPOS.
Publication.
Sousa CNA. 1994. de Cultivares de
trigo recomendadas no Brasil -
1922 a 1992. EMBRAPA-CNPT. Documentos 16, EMBRAPA-CNPT,
Passo Fundo. 82 pp.
C.N.A. de Sousa, E.P. Gomes, J.C.S. Moreira, L. de J.A. Del Duca, and P.L. Scheeren.
The wheat cultivar, EMBRAPA 27,
was selected from the cross `PF83743/5/PF
83182/4/CNT10*4 /LAGOA VERMELHA*5/AGATHA/3/LONDRINA*4/AGENT//LONDRINA*3/NYU
BAY'.
The last cross was made in 1983, bulked
as a line (PF 869107) in 1986, and released for cultivation in
the state of Parana (regions D and F) in 1994. The objective
of the cross was to produce a line using the backcross method,
similar to CNT 10, the prevalent cultivar in the state of Rio
Grande do Sul in 1982, but in a short type and with resistance
to powdery mildew, leaf rust, and stem rust. PF 83743 is a short
CNT 10 and PF 83182 is a CNT 10 with the gene Lr9. Agatha
was used in the cross of EMBRAPA 27 and has the genes Lrl9
and Sr25. Agent has the genes Lr24 and Sr24.
EMBRAPA 27 is resistant to all races of Puccinia graminis
tritici and to Puccinia recondita tritici
found in Brazil, with the exception of the race B 40, detected
for the first time in 1994.
Apparently, because of race B 40, leaf
rust is going to be detrimental to EMBRAPA 27. This cultivar
is short, with a tendency to produce many spikes per area. EMBRAPA
27 is a soft wheat, moderately tolerant to aluminum toxicity.
Survey on leaf tip necrosis and hybrid necrosis (gene Ne2).
C.N.A. de Sousa.
A group of 16 Brazilian wheat cultivars
was tested in 1973 for the presence of leaf tip necrosis like
the one found in Frontana and for hybrid necrosis (gene Ne2)
through crosses using durum wheat with the gene Nel (Karim,
Sacaba 81, and/or Taray 85). Leaf tip necrosis is associated
with the presence of gene Lr34 for resistance to leaf rust,
and gene Ne2 is associated with gene Lrl3, with
a few exceptions.
The data obtained and speculation on
the presence of the genes Lr13 and Lr34 are presented
in the table below.
The presence of leaf tip necrosis was
not clear in the cases of CEP 11, CEP 24-Industrial,
and Trigo BR 4. Apparently, Trigo BR 34, Trigo BR 37, and Trigo
BR 43 do not possess the gene Lrl3, although they have
the gene Ne2. These cultivars are, at present, highly
susceptible to leaf rust.
Additional research on the necrosis
associated with leaf rust resistance in this line is under way.
Possible presence of genes Lr34 and Lr13 and their association with leaf tip and hybrid
necrosis.
_____________________________________________________________________
Cultivar Leaf tip Hybrid Presence of genes
necrosis necrosis* Lr34 Lrl3
_____________________________________________________________________
CEP 11 ? Yes ? +
Cep 14-Tapes No No - -
CEP 24-Industrial ? No ? -
CNT 8 No Yes - +
EMBRAPA 15 No No - -
EMBRAPA 16 No Yes - +
Frontana Yes Yes + +
PAT 7392 No Yes - +
PF 869120 No No - -
PF 87107 No No - -
PF 87453 No No - -
Trigo BR 4 ? Yes ? +
Trigo BR 23 Yes Yes + +
Trigo BR 34 No Yes - +?
Trigo BR 37 No Yes - +?
Trigo BR 43 No Yes - +?
_____________________________________________________________________
*
In the F1 population of cross with Nel genotypes.
1994 wheat cultivar yield trials in Passo Fundo, Brazil.
J.C.S. Moreira and C.N.A. de Sousa.
About 500 wheat genotypes were tested
in 22 yield trials at the National Research Center for Wheat at
EMBRAPA in Passo Fundo, Rio Grande do Sul, Brazil, during 1994.
The process for releasing a new cultivar in Rio Grande do Sul,
the southernmost Brazilian state, was described in the 1986
Annual Wheat Newsletter, 32:38-39.
The climatic conditions during the
wheat cycle in Passo Fundo (June to November) were not good for
wheat. Drought occurred over the period from tillering to stem
extension, and excess rainfall occurred at the ripening stage.
The plants had poor growth, and the yield was lower than that
in 1992 and similar to that in 1993. The excess of rain induced
sprouting. The main leaf diseases were leaf rust, powdery mildew,
and the Septoria/Helminthosporium complex.
The trials were carried out in a rotation
area (2 years without wheat), and fertilizer application was 12.5
kg/ha N, 63 kg/ha P205, 50 kg/ha K20,
and 45 kg/ha N as topdressing. No fungicide was used in most
trials.
The controls used in 1994 were BR 23,
BR 35, and EMBRAPA 16. The best check in yield was EMBRAPA 16.
The cultivar BR 23 continues to be the main cultivar in Rio Grande
do Sul, occupying about 250,000 ha (43 %) of the growing area
in this state in 1994.
No entry exceeded the yield of the
three local checks in the 30th International Spring Wheat Yield
Nursery and in the 15th Elite Selection Wheat Yield Trial, received
from CIMMYT.
Cultivars that yielded more than EMBRAPA
16 in trials carried out in Passo Fundo, RS are shown in the following
table:
___________________________________________________________________________________
Yield
Cultivar Cross (kg/ha)
___________________________________________________________________________________
1. Cultivar State Trial and South Brazilian
Trial.
1.1. Trial without fungicide.
PF 86242 HLN/CNT 7//AMIGO/CNT 7 3,297
PF 90120 BR 35//PF 83619//PF 858/PF 8550 2,870
EMBRAPA 16 (check) HLN/CNT 7//AMIGO/CNT
7 2,828
1.2. Trial with fungicide.
PF 86242 HLN/CNT 7//AMIGO/CNT 7 3,401
BR 23 CC/ALD SIB/3/IAS 54-20/COP//CNT 8 3,126
EMBRAPA 16 (check) HLN/CNT 7//AMIGO/CNT
7 3,027
2. Regional Yield Trial.
PF 9110 IAS 55*6/CI 14123//PF 83323/3/BR 8/PF 3,147
81230//CEP ll/BR 14
EMBRAPA 16 (check) HLN/CNT 7//AMIGO/CNT
7 3,027
3. Multilocation Preliminary Trials (5 sites with lines in 2nd year of test).
Data from Passo Fundo.
PF 92130 PF83619*2/CEP 19 3,073
PF 92141 BR 35/PF 85946/3/PF 772003*2/PF 813//PF 2,820
83899
PF92165 BR 8/BR 25//CEP 11/BR 14/4/CNT 10*5/ST 2,800
1/3/CNT 10*6/IIAS 54-21*2/CI 14123
BR35 IAC 5*2/3/CNT 7*3/LD/IAC/5/HADDEN 2,780
EMBRAPA 16 (check) HLN/CNT 7//AMIGO/CNT
7 2,757
4. Preliminary Trials (1st year trial).
Wheat genotypes out of 352 lines that yielded more than EMBRAPA 16.
PF 92359 BR 14*5//JUP 73*4/AMIGO SEL 3,742 (1011)
PF 9362 COKER 762/CEP 14 4,055 (1031)
___________________________________________________________________________________
1 % OF EMBRAPA 16 (check).