Development and characteristics of new inbred line 'Mi47' of silage maize.

摘要

The new inbred line Mi47 was developed as a parental line of silage maize and was officially registered as Maize Norin Kou Oya 49 in 2000 by the Ministry of Agriculture, Forestry and Fisheries. The development was carried out at Miyazaki Prefectural Agricultural Experiment Station, Japan, from 1988 to 1989, and at National Agricultural Research Center for Kyushu Okinawa Region (formerly Kyushu National Agricultural Research station) from 1990 to 1997. Mi47 was selected from [Mi 9 x {Hirano 1/(JF 1 C 1 . S2 x Iiboshi 2 . S4)} . S2] x (JF 2 C 2 . S4 x Mi15), originating mainly from Japanese native flint strains. Selection was made for improving resistance to lodging and southern leaf blight (Bipolaris maydis [Cochliobolus heterostrophus]), and for high combining ability. Selection and selfing were conducted until the S6 generation. Mi47 belongs to the early-medium maturity group in Kyushu district, and exhibits high lodging resistance. This inbred line shows high resistance to southern leaf blight and sheath blight (Rhizoctonia solani). Mi47 has shorter stalk and ear height, and belongs to the upright plant type. The seed-yielding ability is as high as that of the flint inbred line. The combining ability is high, and its hybrids are excellent in terms of stover digestibility. The new single cross hybrid cultivar Yumechikara, characterized by high lodging resistance, high amount of total digestible nutrients, and high-yielding ability, in the Kyushu, Shikoku and Chugoku districts was developed using Mi47 as the pollen parent.