Meadow bromegrass is a recently introduced pasture grass in western Canada. Its leafy production and rapid regrowth have made it a major grass species for pasturing beef animals in this region. Because relatively little breeding work has been done on this species, there is little information on its breeding behaviour. The main objective of this study was to estimate genetic parameters and assess breeding methodologies for meadow bromegrass. Forty half‐sib (polycross and open‐pollinated) and full‐sib (selfed) progenies were evaluated for dry matter and seed yield, fertility index, harvest index, plant height, plant spread, crude protein, neutral detergent fibre and acid detergent fibre. Genetic variation for seed yield, harvest index, and plant height was significant in the open‐pollinated and selfed tests. Genetic variation estimates for dry matter yield were negative (polycross), not significant (open‐pollinated), or significant (selfed). Estimates of genetic variation for quality traits were not significant, except for acid detergent fibre (selfed). Correlations among characters indicated that it is possible to simultaneously improve seed and forage yield. Rankings of progenies by the half‐sib tests for forage and seed yield were not altered by the use of the synthetic parental value (SVi), which includes information from selfed progeny. The polycross progeny test did not discriminate parents as well as the open‐pollinated and selfed tests; this may have been a result of non‐random pollination in the polycross. Correlation among the progeny tests, showed that open‐pollinated and selfed progeny tests agreed for all characters, except for harvest index, while correlation between polycross and selfed tests were significant for six characters but not dry matter yield, and acid and neutral detergent fibres. The most dissimilar tests were polycross and open‐pollinated, with significant correlations found only for fertility index, height, spread and neutral detergent fibre. It was concluded that there was significant variation and moderate heritability for most traits in the meadow bromegrass populations evaluated, and that the open‐pollinated progeny test is the method of choice for selecting parents for synthetics of this species.

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Resumo -O objetivo deste trabalho foi avaliar a eficiência bioeconômica de cordeiros F 1 Dorper x Santa Inês para produção de carne. Analisou-se o desempenho de ovinos ½ sangue Dorper x ½ sangue Santa Inês, nas fases de cria e de acabamento. A fase de produção das crias foi realizada em caatinga nativa e a fase de acabamento em confinamento. As matrizes foram suplementadas nos últimos 50 dias de prenhez e nos primeiros 30 dias de lactação. As crias foram desmamadas aos 70 dias de idade, divididas em três lotes e confinadas, alimentadas com capim-elefante (Pennisetum purpureum) ad libitum e concentrado na proporção de 1,5%, 2,5% e 3,5% do peso vivo, respectivamente. O sexo não exerceu influência sobre os pesos no nascimento, no desmame, nem sobre o ganho em peso até o desmame. Não foi observada influência do sexo sobre os pesos e os ganhos em peso aos 30 e 50 dias de confinamento. Nas fases de produção e acabamento em confinamento, os animais de nascimento simples foram superiores aos de nascimento duplo quanto a essas variáveis. Houve efeito linear significativo para peso e ganho em peso aos 30 e 50 dias de confinamento. Os três níveis de uso de concentrado foram economicamente viáveis. As margens brutas de peso vivo, por kg de cordeiro produzido, foram de R$ 0,26 kg -1 , R$ 0,30 kg -1 e R$ 0,36 kg -1 para concentrados a 1,5%, 2,5% e 3,5% do peso vivo, respectivamente. Os melhores resultados econômicos foram obtidos quando o nível de concentrado foi de 3,5% do peso vivo.Termos para indexação: ovino, cruzamento industrial, peso corporal, ganho em peso, confinamento, viabilidade econômica. Bioeconomic efficiency of F 1 Dorper x Santa Inês lambs for meet productionAbstract -The objective of this work was to evaluate bioeconomic efficiency of F 1 Dorper x Santa Inês lambs for meet production. Performance of F 1 Dorper x Santa Inês lambs in raising and fattening phases was analyzed. The production phase of lambs was realized in native pastures ("caatinga") and the finishing phase was in confinement. The ewes were supplemented during the last 50 days of pregnancy and the first 30 days of lactation. Lambs were weaned at 70 days of age, divided into three lots, confined and fed elephant grass (Pennisetum purpureum) ad libitum, and concentrate in the proportion of 1.5%, 2.5% and 3.5% of live weight, respectively. Lambs sex did not have significant influence on birth weight, as well as on weaning weight and weight gain until weaning. In production and confinement phases, lambs of single births were superior to double births ones considering these variables. Linear effect was significant for weight and for weight gain, at 30 and 50 days of confinement. The three inclusion levels of concentrate were economically viable. Gross margins of live weight for each kg of lamb produced were R$ 0.26 kg -1 , R$ 0.30 kg -1 and R$ 0.36 kg -1 of live weight to concentrates of 1.5%, 2.5% and 3.5%, respectively. The best economics results were obtained when the concentrate level was 3.5% of live weight.

In March 2006, diseased soybean plants (Glycine max) were found in the municipalities of Passo Fundo and Coxilha, state of Rio Grande do Sul, Brazil, showing withered, brown leaves and light to reddish-brown discoloration and necrosis (canker) of the lower half of the stem. Cultural characteristics in potato dextrose agar showed identical patterns to those described for Diaporthe phaseolorum var. caulivora (Dpc). The rDNA-ITS sequence data from the Brazilian strain CH 40/06 (GenBank accession number EU622854) were compared to homologous sequences from the NCBI GenBank database, and a high similarity with Dpc strains was verified. A phylogenetic reconstruction was performed to compare EU622854 with other related sequences and grouped with Dpc. This group was highly supported by the bootstrap test (99%). Morphology of the Brazilian specimen was also similar to that described in the literature for Dpc, but the ascospores were slightly narrower than the American original material of Dpc. In field surveys performed in the 2006/07 crop season, Dpc was also found in five additional municipalities in RS. Keywords: stem canker, Phomopsis phaseoli f. sp. caulivora, Glycine max. RESUMO Primeiro relato de Diaporthe phaseolorum var. caulivora infectando plantas de soja no BrasilEm março de 2006, plantas de soja (Glycine max) doentes foram encontradas em Passo Fundo e em Coxilha, Rio Grande do Sul, Brasil. O quadro sintomatológico caracterizava-se por plantas com folhas secas e de coloração marrom; necrose (cancro) na metade inferior da haste, de coloração marrom-clara a marrom-avermelhada, envolvendo a mesma, seguindo-se murcha e morte da planta. Características culturais em batata dextrose ágar mostraram padrões idênticos àqueles publicados para Diaporthe phaseolorum var. caulivora (Dpc). Os dados de seqüenciamento de DNA do isolado brasileiro CH 40/06 (número de acesso GenBank EU622854) foram comparados às seqüências homólogas de NCBI GenBank, e alta similaridade foi verificada com outros isolados de Dpc. Árvore filogenética foi elaborada a fim de comparar EU622854 com outras seqüências de Dpc, cujo agrupamento foi altamente confirmado pelo teste bootstrap (99%). Características morfológicas foram similares às descritas para Dpc na literatura, embora os ascosporos do espécime brasileiro fossem mais estreitos que o original americano. Na safra 2006/07, Dpc foi também encontrado em outros cinco municípios do RS. Palavras-chave: cancro da haste, Phomopsis phaseoli f. sp caulivora, Glycine max.

Meadow bromegrass (Bromus riparius Rehm.) is a recently introduced pasture grass in western Canada. Its leafy production and rapid regrowth have made it a major grass species for pasturing beef animals in this region. As relatively little breeding work has been done on this species, there is little information on its breeding behaviour. The main objective of this study was to estimate total genetic variability, broad-sense heritability, phenotypic and genetic correlations. Forty-four meadow bromegrass clones were evaluated for agronomic characters. Genetic variation for dry matter yield, seed yield, fertility index, harvest index, plant height, plant spread, crude protein, neutral detergent fiber and acid detergent fiber, was significant. Broad-sense heritability estimates exceeded 50% for all characters. Heritability estimates were at least 3.5 times greater than their standard errors. Phenotypic and genetic correlation between all possible characters were measured. There was general agreement in both sign and magnitude between genetic and phenotypic correlations. Correlations between the different characters demonstrated that it is possible to simultaneously improve seed and forage yield. Based on the results, it appears that the development of higher yielding cultivars with higher crude protein, and lower acid and neutral detergent fibers concentration should be possible.

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Ds Aneuro, M. R. A., Cour-rraaN For personal use only.

A pesquisa foi conduzida em Sobral, Ceará, no período de janeiro de 1992 a julho de 1994 e objetivou determinar o desempenho produtivo de ovinos, produção de forragem e características fitossociológicas do estrato herbáceo da caatinga raleada submetida à adubação orgânica e pastoreio de curta duração, com duas taxas de lotação. Foram testadas as cargas de 3,3 (leve) e 10 cab/ha (pesada), com (5 t/ha de esterco de caprinos) e sem adubação orgânica. Utilizou-se um delineamento inteiramente casualizado distribuído em um fatorial 2x 2 x 3 (carga animal x adubação x ano), com duas repetições. O pastejo de ovinos resultou no desaparecimento total das gramíneas e no aumento das dicotiledôneas herbáceas no período estudado. A adubação orgânica não mostrou efeitos significantes (P>0,05) quanto à performance animal e das pastagens. O melhor desempenho animal (P<0,01) foi obtido nas parcelas com carga leve (3,3 cab/ha), com 108,0 g/cab/dia e o da pastagem foi observado nas áreas com carga pesada (10 cab/ha) com 71,2 kg/ha/ano. Apesar da elevada produção animal, o pastejo de curta duração, somente com ovinos, não deve ser recomendado para a caatinga raleada, por desestabilizar a composição do estrato herbáceo, principal componente da dieta desses ruminantes. Provavelmente, a alternância com outro herbívoro de hábito de pastejo e preferência alimentar diferente resultará em uma melhor sustentabilidade da exploração.