麦あと晩植栽培に適した早生・良食味の水稲新品種「ほしみのり」の育成

“Hoshiminori”, which is a new rice cultivar with early maturing and good eating quality, was bred by the Institute of Crop Science, NARO (NICS) in 2015. This cultivar was selected from a population derived from the cross between “Kanto 209(Satojiman)” and “Etsunan 171” conducted in 2002. The main characteristics as follows; The heading and maturing dates of “Hoshiminori” are slightly earlier than those of “Asanohikari”. The maturity is classified into “moderately early” in the Kanto region. The culm and panicle lengths are longer than “Asanohikari”, however, the number of panicles per area is less than that of “Asanohikari”. The yield of brown rice is 19% higher than “Asanohikari” in the late-transplanting yield trial tests of NICS. Its eating quality of cooked rice is equivalent to that of “Koshihikari” and is classified into “excellent”. “Hoshiminori” harbors the Stvb-i gene, therefore, shows resistance to the rice stripe virus. “Hoshiminori” is expected to be suitable for late-transplanting in rice-wheat/barley double cropping areas such as the northern Kanto area.「ほしみのり」は，良食味，縞葉枯病抵抗性の「関東209 号（さとじまん）」と良質，良食味の「越南171 号」の交雑後代より育成された，早生，良食味品種である．育成地（農研機構谷和原水田圃場（茨城県つくばみらい市））における「ほしみのり」の特徴は以下の通りである．出穂期，成熟期はともに“やや早” に属し，「朝の光」よりやや早い．「朝の光」と比較して，稈長，穂長は長く，穂数は少ない．草型は“穂重型” である．収量は，「朝の光」に対して，晩植・標肥区で19%，早植・標肥区で8% 多い．炊飯米の食味は「コシヒカリ」並の良食味である．玄米の外観品質は“中の上”，高温登熟性は“やや弱” である．いもち病真性抵抗性遺伝子Pia を持つと推定され，圃場抵抗性は，葉いもちが“中”，穂いもちが“やや弱” である．縞葉枯病抵抗性遺伝子Stvb-i を持ち，縞葉枯病には“抵抗性” で，白葉枯病抵抗性は“中”である．穂発芽性は “難” である．以上の特性から，「ほしみのり」は，北関東を中心とした麦あと晩植地帯向けの品種として，普及・活用が期待される