Root knot nematodes are top priority nematode pests that significantly constrain agricultural productivity globally especially in developing countries. However, expressing double stranded RNA (dsRNA) of essential nema...Root knot nematodes are top priority nematode pests that significantly constrain agricultural productivity globally especially in developing countries. However, expressing double stranded RNA (dsRNA) of essential nematode genes in susceptible plants is known to confer protection against these pests via RNA silencing. This molecular-based strategy is called host induced gene silencing (HIGS) and the selection of appropriate target nematode gene is critical to its success. In this study, therefore, we focused on root knot nematode PolA1, an essential single copy nuclear gene encoding the largest subunit of RNA polymerase I enzyme and evaluated its effectiveness as a target in conferring nematode resistance on Agrobacterium-mediated transformed tobacco plants. Transgenic tobacco expressing Meloidogyne incognita-specific (MiS) dsRNA of PolA1 gene showed significant reduction in nematode fecundity and multiplication compared to wild type plants in both T0 and T1 generations. T0 plants showed varying degrees of agronomic vigorover WT plants possibly due to varying levels of processed siRNA. However, production of MiS siRNAs in the transgenic plants coupled with significant reduction of PolA1 transcript expression in nematodes feeding on roots of transgenic plants provided evidence of HIGS. Taken together, our results show that PolA1 is a potentially effective target for HIGS-mediated reduction of root knot nematode damage on transgenic tobacco. Given the homology of our target sequence among Meloidogyne species, this protection could be broad range against other root knot nematodes aside M. incognita.展开更多
Advanced driver assistance systems, especially autonomous emergency braking and forward collision warnings, have becomepopular in Japan. To reduce the number of road traffic accidents, safety information should be pro...Advanced driver assistance systems, especially autonomous emergency braking and forward collision warnings, have becomepopular in Japan. To reduce the number of road traffic accidents, safety information should be provided to a driver earlier thanavoidance or warning messages so as to avoid a risky situation. A series of actual running tests was conducted to evaluate theactivation timing and effectiveness of awareness messages. Objective analysis showed that the drivers could avoid an obstaclewith a sufficient safety margin thanks to any of the awareness messages. Subjective ratings showed that the best timing is 10 sbefore encountering the obstacle. The results of objective analysis are limited in the present paper, and further analyses arerequired.展开更多
文摘Root knot nematodes are top priority nematode pests that significantly constrain agricultural productivity globally especially in developing countries. However, expressing double stranded RNA (dsRNA) of essential nematode genes in susceptible plants is known to confer protection against these pests via RNA silencing. This molecular-based strategy is called host induced gene silencing (HIGS) and the selection of appropriate target nematode gene is critical to its success. In this study, therefore, we focused on root knot nematode PolA1, an essential single copy nuclear gene encoding the largest subunit of RNA polymerase I enzyme and evaluated its effectiveness as a target in conferring nematode resistance on Agrobacterium-mediated transformed tobacco plants. Transgenic tobacco expressing Meloidogyne incognita-specific (MiS) dsRNA of PolA1 gene showed significant reduction in nematode fecundity and multiplication compared to wild type plants in both T0 and T1 generations. T0 plants showed varying degrees of agronomic vigorover WT plants possibly due to varying levels of processed siRNA. However, production of MiS siRNAs in the transgenic plants coupled with significant reduction of PolA1 transcript expression in nematodes feeding on roots of transgenic plants provided evidence of HIGS. Taken together, our results show that PolA1 is a potentially effective target for HIGS-mediated reduction of root knot nematode damage on transgenic tobacco. Given the homology of our target sequence among Meloidogyne species, this protection could be broad range against other root knot nematodes aside M. incognita.
文摘Advanced driver assistance systems, especially autonomous emergency braking and forward collision warnings, have becomepopular in Japan. To reduce the number of road traffic accidents, safety information should be provided to a driver earlier thanavoidance or warning messages so as to avoid a risky situation. A series of actual running tests was conducted to evaluate theactivation timing and effectiveness of awareness messages. Objective analysis showed that the drivers could avoid an obstaclewith a sufficient safety margin thanks to any of the awareness messages. Subjective ratings showed that the best timing is 10 sbefore encountering the obstacle. The results of objective analysis are limited in the present paper, and further analyses arerequired.
