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新潟県が開発した紫黒糯米品種「紫宝」の収量,玄米品質・成分,ポリフェノール含呈および餅加工特性の高位安定栽培技術を検討するため,2006~2007年に新潟県内で栽培試験と現地調査を行った.その結果,「紫宝」は,施肥窒素成分量が多く,出穂期が早く,登熟気温が高いほど,穂数が多く多収となった.餅加工特性は登熟気温が高いほど高かったが,ポリフェノール含量は登熟気温が高いほど低かったことから,収量および餅加工特性とポリフェノール含量とを同時に高めることは,栽培技術的に困難と考えられた.ポリフェノール含量を重視した「紫宝」の栽培では,その収量性と餅加工特性は低くなる可能性が高いという知見を現場に周知する一方,餅生地が硬くなりにくいという特性を活かした加工利用が重要と考えられた.「紫宝」の農業形質や玄米成分,餅加工特性には栽培地域間で差異が認められ,病害虫の種類や被害程度も多様であったことから,地域の気象条件や農法に応じた栽培指針を早急に整備する必要があると考えられた., The black-kerneled glutinous rice cultivar ‘Shiho’ was recently released in Niigata Prefecture, but the relationships among yield, polyphenol content and characteristics for rice cake processing have not been discussed precisely. We carried out the cultivation experiment under different conditions at several locations in Niigata Prefecture in 2006 and 2007, and examined various agronomic characters and grain properties of ‘Shiho’. Higher yield of ‘Shiho’ was attained by increasing the number of panicles per unit area by heavy manuring and the higher temperature during the ripening period. The higher temperature during the ripening period also resulted in the superior characteristics for rice cake processing, however lower content of polyphenol. Thus, it is difficult to find an appropriate cultivation method for satisfying simultaneously both yield and grain characteristics of ‘Shiho’ in higher order. It should be announced previously to rice farmers and the rice cake processed food company that ‘Shiho’ with higher polyphenol content could result in lower yield and inferior characteristics for rice cake processing. It may be important to develop of products characterized by keeping softness for a long period. ‘Shiho’ cultivated in different areas in Niigata prefecture showed marked differences in agronomic traits, ingredient of kernel and characteristics for rice cake processing, and damage by various diseases and pests. The cultivation methods need to be improved for various climatic conditions and farming systems in the mountainous region.