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BRS 254 – Wheat cultivar for irrigated conditions  [PDF]
Márcio Só e Silva,Julio César Albrecht,Eduardo Caierao,Pedro L. Scheeren
Crop Breeding and Applied Biotechnology , 2008,
Abstract: The wheat cultivar BRS 254 was developed by Embrapa. It resulted from a cross between Embrapa 22*3 andAnahuac 75. The gluten strength of BRS 254 is high and the cultivar is suited for irrigated conditions.
Resistência parcial à brusone em somaclones da cultivar de arroz CICA-8
Araújo, Leila G.;Prabhu, Anne S.;
Fitopatologia Brasileira , 2004, DOI: 10.1590/S0100-41582004000400006
Abstract: the development of rice blast resistance sources is a basic requirement for rice (oryza sativa) breeding. the main objective of this investigation was to evaluate somaclones of rice cultivar cica-8, developed from callus cultures of immature panicles for blast resistance. rice blast in 39 somaclones was assessed in the advanced generations from r5 to r7, in the blast nursery under natural conditions of infection and in greenhouse inoculation tests, using five isolates pertaining to four pathotypes (id-14, ii-1, ib-1 and ib-45) of pyricularia grisea. in the rice blast nursery, somaclones exhibited differences in disease reactions. in inoculation tests, somaclones showed differential interaction between isolates of the pathogen and genotypes. two isolates highly virulent to five somaclones including cica-8 and co 39 were selected to determine the partial resistance. there was no significant interaction between isolates and somaclones for partial resistance index, determined based on leaf lesion number per cm2. four somaclones showed significantly higher degree of partial resistance when compared with the parent cultivar cica-8.
DNA tagging of blast resistant gene(s) in three Brazilian rice cultivars
Sandhu, S.S.;Colombo, Carlos;Bastos, Candido R.;Siqueira, Walter J.;
Genetics and Molecular Biology , 2003, DOI: 10.1590/S1415-47572003000400011
Abstract: rice blast is the most important fungal disease of rice and is caused by pyricularia oryzae sacc. (telomorph magnoporthe grisea barr.). seven randomly amplified polymorphic dna (rapd) markers opa5, opg17, opg18, opg19, opf9, opf17 and opf19 showed very clear polymorphism in resistant cultivar lines which differed from susceptible lines. by comparing different susceptible lines, nine dna amplifications of seven primers (opa51000, opa51200, opg17700, opg18850, opg19500, opg19600, opf9600, opf171200 and opf19600) were identified as dominant markers for the blast resistant gene in resistant cultivar lines. these loci facilitate the indirect scoring of blast resistant and blast susceptible genotypes. the codomine rapds markers will facilitate marker-assisted selection of the blast resistant gene in two blast resistant genotypes of rice (labelle and line 11) and will be useful in rice breeding programs.
DNA tagging of blast resistant gene(s) in three Brazilian rice cultivars  [cached]
Sandhu S.S.,Colombo Carlos,Bastos Candido R.,Siqueira Walter J.
Genetics and Molecular Biology , 2003,
Abstract: Rice blast is the most important fungal disease of rice and is caused by Pyricularia oryzae Sacc. (Telomorph Magnoporthe grisea Barr.). Seven randomly amplified polymorphic DNA (RAPD) markers OPA5, OPG17, OPG18, OPG19, OPF9, OPF17 and OPF19 showed very clear polymorphism in resistant cultivar lines which differed from susceptible lines. By comparing different susceptible lines, nine DNA amplifications of seven primers (OPA5(1000), OPA5(1200,) OPG17(700), OPG18(850), OPG19(500), OPG19(600), OPF9(600), OPF17(1200) and OPF19(600)) were identified as dominant markers for the blast resistant gene in resistant cultivar lines. These loci facilitate the indirect scoring of blast resistant and blast susceptible genotypes. The codomine RAPDs markers will facilitate marker-assisted selection of the blast resistant gene in two blast resistant genotypes of rice (Labelle and Line 11) and will be useful in rice breeding programs.
Soluble tissue sugar content and leaf blast severity in response to the application of calcinated serpentinite as a silicon source in irrigated rice
Prabhu, Anne Sitarama;Santos, Alberto Baêta dos;Didonet, Agostinho Dirceu;
Summa Phytopathologica , 2007, DOI: 10.1590/S0100-54052007000400014
Abstract: a field experiment conducted with the irrigated rice cultivar brs formoso, to assess the efficiency of calcinated serpentinite as a silicon source on grain yield was utilized to study its effect on leaf blast severity and tissue sugar levels. the treatments consisted of five rates of calcinated serpentinite (0, 2, 4, 6, 8 mg.ha-1) incorporated into the soil prior to planting. the leaf blast severity was reduced at the rate of 2.96% per ton of calcinated serpentinite. the total tissue sugar content decreased significantly as the rates of serpentinite applied increased (r2 = 0.83). the relationship between the tissue sugar content and leaf blast severity was linear and positive (r2 = 0.81). the decrease in leaf blast severity with increased rates of calcinated serpentinite was also linear (r2= 0.96) and can be ascribed to reduced sugar level.
Cultivar response to fungicide application in relation to rice blast control, productivity and sustainability
Prabhu, Anne Sitarama;Filippi, Marta Cristina;Zimmermann, Francisco José Pfeilsticker;
Pesquisa Agropecuária Brasileira , 2003, DOI: 10.1590/S0100-204X2003000100002
Abstract: four field trials were conducted, from 1995 to 1997, with the objective of studying the response of four upland cultivars to foliar fungicide application in relation to panicle blast control, grain yield and sustainability. differential disease control and yield response of cultivars to fungicide treatment were obtained. losses in grain yield of cultivars iac 202, caiapó, rio paranaíba and araguaia due to panicle blast were 44.8%, 27.4%, 24.4% and 18.2%, respectively. two applications of tricyclazole or benomyl controlled panicle blast, as indicated by lower values of disease progress curve and relative panicle blast severity, and increased grain yield of the cultivar iac 202. the losses in 100 panicle grain weight and grain yield were significantly reduced by 22.3% and 25.1% in iac 202 and 23.6% and 20.5% in caiapó, respectively, with two sprays of tricyclazole. sustainable value index for yield was maximum with two applications of tricyclazole (0.59), followed by one application at booting (0.46) and at heading (0.40) in cultivar iac 202. results showed no yield response of the cultivars rio paranaíba and araguaia to fungicide applications for panicle blast control.
Cultivar response to fungicide application in relation to rice blast control, productivity and sustainability  [cached]
Prabhu Anne Sitarama,Filippi Marta Cristina,Zimmermann Francisco José Pfeilsticker
Pesquisa Agropecuária Brasileira , 2003,
Abstract: Four field trials were conducted, from 1995 to 1997, with the objective of studying the response of four upland cultivars to foliar fungicide application in relation to panicle blast control, grain yield and sustainability. Differential disease control and yield response of cultivars to fungicide treatment were obtained. Losses in grain yield of cultivars IAC 202, Caiapó, Rio Paranaíba and Araguaia due to panicle blast were 44.8%, 27.4%, 24.4% and 18.2%, respectively. Two applications of tricyclazole or benomyl controlled panicle blast, as indicated by lower values of disease progress curve and relative panicle blast severity, and increased grain yield of the cultivar IAC 202. The losses in 100 panicle grain weight and grain yield were significantly reduced by 22.3% and 25.1% in IAC 202 and 23.6% and 20.5% in Caiapó, respectively, with two sprays of tricyclazole. Sustainable value index for yield was maximum with two applications of tricyclazole (0.59), followed by one application at booting (0.46) and at heading (0.40) in cultivar IAC 202. Results showed no yield response of the cultivars Rio Paranaíba and Araguaia to fungicide applications for panicle blast control.
CULTIVAR RELEASE-BRSMG Predileta: irrigated rice cultivar for lowlands in Minas Gerais, Brazil  [PDF]
Plínio César Soares,Ant?nio Alves Soares,Vanda Maria de Oliveira Cornélio,Moizés de Souza Reis
Crop Breeding and Applied Biotechnology , 2008,
Abstract: The cultivar of irrigated rice BRSMG Predileta has high grain yield, resistance to the main rice diseases andproduces good quality grains for industry and cooking. It was recommended in 2007 by the Genetic Improvement Programfor lowland rice in Minas Gerais, developed by EPAMIG in partnership with Embrapa Arroz e Feij o.
Development of blast resistant somaclones of the upland rice cultivar araguaia
ARAúJO, LEILA GARCêS DE;PRABHU, ANNE SITARAMA;FREIRE, ADELSON DE BARROS;
Pesquisa Agropecuária Brasileira , 2000, DOI: 10.1590/S0100-204X2000000200015
Abstract: the degree of blast resistance of upland rice (oryza sativa l.) cultivar araguaia has decreased over time causing significant yield losses. the major objective of this study was to obtain blast (pyricularia grisea) resistant somaclones, adapting greenhouse and field selection procedures. rice blast resistance and agronomic traits were assessed in r2 to r6 generations derived from regenerant plants (r1) from immature panicles of araguaia. the evaluation and selection procedures include testing of early segregating populations and fixed lines in the advanced generations, under natural field conditions, and artificial inoculations in the greenhouse, with prevalent races ib-1 and ib-9 of p. grisea. somaclones with both vertical resistance and slow blasting resistance were obtained. twenty of 31 somaclones developed with a high degree of vertical resistance and fan shaped plant type maintained resistance in field and blast nursery tests in the r6 generation. greenhouse selection with two specific physiologic races yielded 44 somaclones with slow blasting resistance, similar plant type and yield potential as that of araguaia.
Development of blast resistant somaclones of the upland rice cultivar araguaia
ARAúJO LEILA GARCêS DE,PRABHU ANNE SITARAMA,FREIRE ADELSON DE BARROS
Pesquisa Agropecuária Brasileira , 2000,
Abstract: The degree of blast resistance of upland rice (Oryza sativa L.) cultivar Araguaia has decreased over time causing significant yield losses. The major objective of this study was to obtain blast (Pyricularia grisea) resistant somaclones, adapting greenhouse and field selection procedures. Rice blast resistance and agronomic traits were assessed in R2 to R6 generations derived from regenerant plants (R1) from immature panicles of Araguaia. The evaluation and selection procedures include testing of early segregating populations and fixed lines in the advanced generations, under natural field conditions, and artificial inoculations in the greenhouse, with prevalent races IB-1 and IB-9 of P. grisea. Somaclones with both vertical resistance and slow blasting resistance were obtained. Twenty of 31 somaclones developed with a high degree of vertical resistance and fan shaped plant type maintained resistance in field and blast nursery tests in the R6 generation. Greenhouse selection with two specific physiologic races yielded 44 somaclones with slow blasting resistance, similar plant type and yield potential as that of Araguaia.
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