甜玉米自交系萌芽期耐寒性的鉴定及筛选

Identification and screening of chilling tolerance of sweet corn inbred lines in seedling emergence stage

以广东省农科院作物研究所的165份甜玉米自交系作为试验材料,在人工气候箱中4℃低温处理7 d后正常发芽,发芽7 d后调查发芽率、胚根长度,并计算活力指数、相对活力指数、相对发芽率等指标。结果表明,低温处理后大部分材料的发芽率和胚根长度降低,但有25份材料的相对发芽率≥100%,52份材料的相对活力指数≥100%,结合这两个因素有24份材料的相对发芽率和相对活力指数均≥100%,其中又有9份材料的正常发芽率≥90%,这9份材料耐寒性较强。同时,筛选出一批低温敏感型的自交系,为甜玉米的耐寒性育种和遗传机理研究提供了优异种质资源。

In order to identify the chilling tolerance in seedling emergence stage and select the sweet inbred lines with strong cold resistance, the chilling tolerance experiment was carried out in 165 sweet corn inbred lines of Crops Research Institute （ CRI ） , Guangdong Academy of Agricultural Sciences. The 165 inbred lines were treated for 7 days at 4℃, then germination test at 25 ℃. After 7 days normal germination, the germination rate and radicle length were investigated. The vigor index, relative vigor index and relative germination rate were calculated. Results showed that the germination rate and radicle length of most materials reduced, but the relative germination rate was 100% or higher for 25 inbred lines, the relative vigor index was 100% or higher for 52 inbred lines. 24 inbred lines had both relative germination rate and relative vigor index with 100% or higher. The normal germination rate was 90% or higher for 9 inbred lines in these 24 materials. So, these 9 inbred lines which had high germination rate and strong cold resistance were filtered. At the same time, a group of low temperature sensitive inbred lines were selected. These materials were excellent germplasm resources for cold resistance breeding and genetic mechanism of cold tolerance.