共生細菌による生殖操作に対する宿主の抵抗形質の進化

この博士論文は内容の要約のみの公開（または一部非公開）になっています筑波大学 (University of Tsukuba)201

Melanic mutation causes a fitness decline in bean beetles infected by Wolbachia

Wolbachia cannot live outside a host, which is thought to be the reason for host‐Wolbachia coevolution toward benign parasitism, especially because the fitness of Wolbachia is traded against its host\u27s fitness. Insect melanism has been reported to have a positive effect on pathogen resistance, but melanic mutants of Callosobruchus analis (Fabricius) and Callosobruchus chinensis (L.) (Coleoptera: Chrysomelidae) are infected with Wolbachia. Callosobruchus chinensis is infected with CI‐inducing Wolbachia, and melanic mutants exhibit fitness decline. Interestingly, this decline is not observed in C. analis melanic mutants that are infected with CI‐free Wolbachia. Our research question is whether the infection of CI‐inducing Wolbachia causes fitness decline of melanic hosts in C. analis. We examined fecundity, fertility, and longevity of C. analis melanic mutants and compared them between uninfected and infected hosts with CI‐inducing Wolbachia. Infected melanic mutants of C. analis exhibited fitness decline leading to reduced hatch rates even when parental combinations were compatible. Wolbachia can invade a host population by causing CI to decrease the fraction of uninfected hosts, but melanic mutant hosts decrease the number of infected hosts through fitness decline. Nevertheless, the melanism in hosts is not able to stop Wolbachia invasion in C. analis

Towards deepening of multi-omics integrated approach in root system to develop climate-resilient rice

Root is the only organ to uptake water and nutrients from soil. Root system is crucial for plants to survive and/or adapt to environmental stresses, therefore, root system architecture (RSA) is an important breeding target for developing climate-resilient rice. Since the rice genome has been completely sequenced, many genes for root development were cloned and characterized so far. In addition, with the advances in technologies related to omics analysis such as high-throughput sequencer, transcriptome analysis of roots has also been progressed. In contrast, high-throughput root phenotyping has not been established in not only rice but also whole plants because root is hidden underground. This should be a bottleneck for utilizing multi-omics integrated approach for molecular breeding of RSA. We first summarize previous transcriptome analysis for root development under various abiotic stresses such as drought, salinity, heat etc. and overview current status of root phenotyping technology and modelling in rice. These knowledges would allow us to contemplate a possibility of applying of integrated multi-omics data of RSA to molecular breeding of climate-resilient rice