As an important oil crop and a potential bioenergy crop, Brassica napus L. is becoming a model plant for basic research on seed lipid biosynthesis as well as seed oil content, which has always been the key breeding ob...As an important oil crop and a potential bioenergy crop, Brassica napus L. is becoming a model plant for basic research on seed lipid biosynthesis as well as seed oil content, which has always been the key breeding objective. In this review, we present current progress in understanding of the regulation of oil content in B. napus, including genetics, biosynthesis pathway,transcriptional regulation, maternal effects and QTL analysis. Furthermore, the history of breeding for high oil content in B. napus is summarized and the progress in breeding ultra-high oil content lines is described. Finally,prospects for breeding high oil content B. napus cultivars are outlined.展开更多
Information on mechanisms and inheritance of resistance is critical to plan an effective strategy to breed for resistance to insect pests. Therefore, we evaluated a diverse array of chickpea genotypes (eight desi and ...Information on mechanisms and inheritance of resistance is critical to plan an effective strategy to breed for resistance to insect pests. Therefore, we evaluated a diverse array of chickpea genotypes (eight desi and one kabuli) with varying levels of resistance to the pod borer, Helicoverpa armigera to gain an understanding of the nature of gene action and possible maternal effects. The test genotypes were crossed in all possible combinations for a full diallel. The 72 F1s (36 direct and 36 reciprocal crosses) along with the parents were evaluated for resistance to H. armigera under field conditions, and for antibiosis mechanism of resistance (larval survival and larval weight gain) by using detached leaf assay under laboratory conditions, and grain yield under un-protected conditions in the field. Additive gene action governed the inheritance of resistance to H. armigera, while non-additive type of gene action was predominant for inheritance of antibiosis component of resistance (larval survival and larval weight) and grain yield. Greater magnitude of σ2 A(17.39 and 1.42) than σ2 D (3.93 and 1.21) indicated the preponderance of σ2 Ain inheritance of resistance to pod borer, H. armigera under laboratory and field conditions, respectively. There were no maternal effects for inheritance of resistance to pod borer and grain yield. Lines with significant gca effects for pod borer damage and grain yield were identified for further use in the resistance breeding program. The implications of the inheritance pattern of pod borer resistance and grain yield are discussed in the context of strategies to enhance pod borer resistance and grain yield in chickpea.展开更多
Background: Accurately assigning hatchlings to the eggs from which they hatched is a prerequisite to understanding how the composition and environment of eggs affect the growth and survival of nestlings. Correctly ass...Background: Accurately assigning hatchlings to the eggs from which they hatched is a prerequisite to understanding how the composition and environment of eggs affect the growth and survival of nestlings. Correctly assigning hatchlings to their eggs can be a challenging endeavor, however, because multiple eggs within the same clutch can hatch at essentially the same time. Egg and hatchling mass are highly correlated in most bird species, and thus assigning eggs to hatchlings using their relative mass(e.g., matching the heaviest hatchling to the heaviest candidate egg) could prove extremely useful.Methods: To assess its potential utility, I applied relative mass assignment(RMA) retrospectively to a dataset of 133 Common Grackle(Quiscalus quiscula) nests in which all egg-hatchling dyads were determined unequivocally.Results: I found that RMA correctly assigned approximately 90% of hatchlings to their eggs when 2-4 hatchlings were present between checks. The number of nests in which hatchlings could not be assigned to their egg, however, increased monotonically from 13 to 46 to 78% for nests containing 2, 3, and 4 hatchlings, respectively, due to the greater likelihood that the mass of hatchlings or their candidate eggs was identical.Conclusions: Although RMA correctly identified the vast majority of egg-hatchling dyads, researchers should use this method with caution, because it will always inflate positive egg-size effects and thus could potentially result in erroneously reporting significant effects.展开更多
Mammalian feeding behavior is often acquired or improved by learning. Social learners are thought to attain novel information or skills faster and at lower cost than asocial learners. In this study, we examined what t...Mammalian feeding behavior is often acquired or improved by learning. Social learners are thought to attain novel information or skills faster and at lower cost than asocial learners. In this study, we examined what types of learning affect the acquisition of efficient feeding behavior by the wood mouse Apodemus speciosus when feeding on large, hard-shelled walnuts. In house cages, na?ve mice acquired an efficient feeding manner during the 14-day conditioning to walnuts, suggesting individual trial-and-error learning contributes to their feeding skills. Social factors such as learning from walnuts that have been opened by other individuals or by observing walnut consumption by proficient conspecifics did not affect the rate of acquisition of efficient feeding. However, weaned offspring could eat walnuts more efficiently and frequently if the mother had been given walnuts during her rearing period. Thus, the skill is likely transmitted between the mother and offspring in addition to individual self-learning.展开更多
基金supported by the National Key Basic Research Program of China (2015CB150200)the National High Technology Research and Development Program of China (2013AA102602)
文摘As an important oil crop and a potential bioenergy crop, Brassica napus L. is becoming a model plant for basic research on seed lipid biosynthesis as well as seed oil content, which has always been the key breeding objective. In this review, we present current progress in understanding of the regulation of oil content in B. napus, including genetics, biosynthesis pathway,transcriptional regulation, maternal effects and QTL analysis. Furthermore, the history of breeding for high oil content in B. napus is summarized and the progress in breeding ultra-high oil content lines is described. Finally,prospects for breeding high oil content B. napus cultivars are outlined.
文摘Information on mechanisms and inheritance of resistance is critical to plan an effective strategy to breed for resistance to insect pests. Therefore, we evaluated a diverse array of chickpea genotypes (eight desi and one kabuli) with varying levels of resistance to the pod borer, Helicoverpa armigera to gain an understanding of the nature of gene action and possible maternal effects. The test genotypes were crossed in all possible combinations for a full diallel. The 72 F1s (36 direct and 36 reciprocal crosses) along with the parents were evaluated for resistance to H. armigera under field conditions, and for antibiosis mechanism of resistance (larval survival and larval weight gain) by using detached leaf assay under laboratory conditions, and grain yield under un-protected conditions in the field. Additive gene action governed the inheritance of resistance to H. armigera, while non-additive type of gene action was predominant for inheritance of antibiosis component of resistance (larval survival and larval weight) and grain yield. Greater magnitude of σ2 A(17.39 and 1.42) than σ2 D (3.93 and 1.21) indicated the preponderance of σ2 Ain inheritance of resistance to pod borer, H. armigera under laboratory and field conditions, respectively. There were no maternal effects for inheritance of resistance to pod borer and grain yield. Lines with significant gca effects for pod borer damage and grain yield were identified for further use in the resistance breeding program. The implications of the inheritance pattern of pod borer resistance and grain yield are discussed in the context of strategies to enhance pod borer resistance and grain yield in chickpea.
基金Funding was provided by the University of Illinois,Program in Ecology,Evolution and Conservationthe American Ornithologists’Union Research Award.L.S.Johnson provided useful comments on an earlier version of the manuscriptsupported by an NSF International Fellowship OISE-1159178
文摘Background: Accurately assigning hatchlings to the eggs from which they hatched is a prerequisite to understanding how the composition and environment of eggs affect the growth and survival of nestlings. Correctly assigning hatchlings to their eggs can be a challenging endeavor, however, because multiple eggs within the same clutch can hatch at essentially the same time. Egg and hatchling mass are highly correlated in most bird species, and thus assigning eggs to hatchlings using their relative mass(e.g., matching the heaviest hatchling to the heaviest candidate egg) could prove extremely useful.Methods: To assess its potential utility, I applied relative mass assignment(RMA) retrospectively to a dataset of 133 Common Grackle(Quiscalus quiscula) nests in which all egg-hatchling dyads were determined unequivocally.Results: I found that RMA correctly assigned approximately 90% of hatchlings to their eggs when 2-4 hatchlings were present between checks. The number of nests in which hatchlings could not be assigned to their egg, however, increased monotonically from 13 to 46 to 78% for nests containing 2, 3, and 4 hatchlings, respectively, due to the greater likelihood that the mass of hatchlings or their candidate eggs was identical.Conclusions: Although RMA correctly identified the vast majority of egg-hatchling dyads, researchers should use this method with caution, because it will always inflate positive egg-size effects and thus could potentially result in erroneously reporting significant effects.
文摘Mammalian feeding behavior is often acquired or improved by learning. Social learners are thought to attain novel information or skills faster and at lower cost than asocial learners. In this study, we examined what types of learning affect the acquisition of efficient feeding behavior by the wood mouse Apodemus speciosus when feeding on large, hard-shelled walnuts. In house cages, na?ve mice acquired an efficient feeding manner during the 14-day conditioning to walnuts, suggesting individual trial-and-error learning contributes to their feeding skills. Social factors such as learning from walnuts that have been opened by other individuals or by observing walnut consumption by proficient conspecifics did not affect the rate of acquisition of efficient feeding. However, weaned offspring could eat walnuts more efficiently and frequently if the mother had been given walnuts during her rearing period. Thus, the skill is likely transmitted between the mother and offspring in addition to individual self-learning.
