Common bean is an important but often a disease-susceptible legume crop of temperate,subtropical and tropical regions worldwide. The crop is affected by bacterial, fungal and viral pathogens. The strategy of resistanc...Common bean is an important but often a disease-susceptible legume crop of temperate,subtropical and tropical regions worldwide. The crop is affected by bacterial, fungal and viral pathogens. The strategy of resistance-gene homologue(RGH) cloning has proven to be an efficient tool for identifying markers and R(resistance) genes associated with resistances to diseases. Microsatellite or SSR markers can be identified by physical association with RGH clones on large-insert DNA clones such as bacterial artificial chromosomes(BACs). Our objectives in this work were to identify RGH-SSR in a BAC library from the Andean genotype G19833 and to test and map any polymorphic markers to identify associations with known positions of disease resistance genes. We developed a set of specific probes designed for clades of common bean RGH genes and then identified positive BAC clones and developed microsatellites from BACs having SSR loci in their end sequences. A total of 629 new RGH-SSRs were identified and named BMr(bean microsatellite RGH-associated markers). A subset of these markers was screened for detecting polymorphism in the genetic mapping population DOR364 × G19833. A genetic map was constructed with a total of 264 markers,among which were 80 RGH loci anchored to single-copy RFLP and SSR markers. Clusters of RGH-SSRs were observed on most of the linkage groups of common bean and in positions associated with R-genes and QTL. The use of these new markers to select for disease resistance is discussed.展开更多
A study was conducted to evaluate the effect of the dietary inclusion of full-fat flaxseed of full-fat sunflower seeds on performance parameters,egg quality parameters and egg yolk fatty acid profile in laying hens.A ...A study was conducted to evaluate the effect of the dietary inclusion of full-fat flaxseed of full-fat sunflower seeds on performance parameters,egg quality parameters and egg yolk fatty acid profile in laying hens.A total of 150 Babcock Brown hens at 27 weeks of age were distributed in 3 experimental treatments,as follows:T1,control;T2,diet containing 13.5% full-fat whole flaxseed seeds;and T3,diet containing 13.5% full-fat ground sunflower seeds.Feed and water were provided ad libitum and the experiment lasted for 8 weeks.No significant differences were found on egg quality parameters,but total egg production and rate of lay were significantly(P <0.05) lower in the group receiving sunflower seeds compared with the control,and significant differences(P <0.05) in egg yolk saturated,monounsaturated,polyunsaturated,omega-6(n-6) and omega-3(n-3) fatty acids were observed,as well as in the n-6:n-3 ratio.The results show that the dietary inclusion of 13.5% flaxseed full-fat seeds significantly increases the n-3 polyunsaturated fatty acid(PUFA) content in the eggs and lowers the n-6:n-3 ratio without affecting performance parameters.Inclusion of full-fat sunflower seeds increases the n-6 PUFA content but affects total egg production and rate of lay.Further studies are needed to determine the level of inclusion of full-fat sunflower seeds that does not affect performance.展开更多
文摘Common bean is an important but often a disease-susceptible legume crop of temperate,subtropical and tropical regions worldwide. The crop is affected by bacterial, fungal and viral pathogens. The strategy of resistance-gene homologue(RGH) cloning has proven to be an efficient tool for identifying markers and R(resistance) genes associated with resistances to diseases. Microsatellite or SSR markers can be identified by physical association with RGH clones on large-insert DNA clones such as bacterial artificial chromosomes(BACs). Our objectives in this work were to identify RGH-SSR in a BAC library from the Andean genotype G19833 and to test and map any polymorphic markers to identify associations with known positions of disease resistance genes. We developed a set of specific probes designed for clades of common bean RGH genes and then identified positive BAC clones and developed microsatellites from BACs having SSR loci in their end sequences. A total of 629 new RGH-SSRs were identified and named BMr(bean microsatellite RGH-associated markers). A subset of these markers was screened for detecting polymorphism in the genetic mapping population DOR364 × G19833. A genetic map was constructed with a total of 264 markers,among which were 80 RGH loci anchored to single-copy RFLP and SSR markers. Clusters of RGH-SSRs were observed on most of the linkage groups of common bean and in positions associated with R-genes and QTL. The use of these new markers to select for disease resistance is discussed.
文摘A study was conducted to evaluate the effect of the dietary inclusion of full-fat flaxseed of full-fat sunflower seeds on performance parameters,egg quality parameters and egg yolk fatty acid profile in laying hens.A total of 150 Babcock Brown hens at 27 weeks of age were distributed in 3 experimental treatments,as follows:T1,control;T2,diet containing 13.5% full-fat whole flaxseed seeds;and T3,diet containing 13.5% full-fat ground sunflower seeds.Feed and water were provided ad libitum and the experiment lasted for 8 weeks.No significant differences were found on egg quality parameters,but total egg production and rate of lay were significantly(P <0.05) lower in the group receiving sunflower seeds compared with the control,and significant differences(P <0.05) in egg yolk saturated,monounsaturated,polyunsaturated,omega-6(n-6) and omega-3(n-3) fatty acids were observed,as well as in the n-6:n-3 ratio.The results show that the dietary inclusion of 13.5% flaxseed full-fat seeds significantly increases the n-3 polyunsaturated fatty acid(PUFA) content in the eggs and lowers the n-6:n-3 ratio without affecting performance parameters.Inclusion of full-fat sunflower seeds increases the n-6 PUFA content but affects total egg production and rate of lay.Further studies are needed to determine the level of inclusion of full-fat sunflower seeds that does not affect performance.
