The new types of cytoplasmic male sterility
Bao I, Bao II were bred by using the approaches of self pollination, selection
and inoculation determination etc. In test-cross of 86 inbred lines to
Bao I type, 45 inbred lines were restored to fertility, covering 52.3%
of the total tested lines, nine were partly restored to fertility, covering
10.5%, 32 lines kept up sterility, covering 37.2%. In test cross of 80
inbred lines to Bao II type, all tested lines kept up sterility (see Table
|Item||Bao I||Bao II|
|Full restoration (_)||45 lines||0|
|Partial restoration (±)||9 lines||0|
|Full maintenance (_)||32 lines||80 lines|
The results obtained from evaluation of resistance to Helminthosporium maydis have shown that E157-cms-Bao I is infected with race 0, but resistant to race T, quite resistant to race C; F157-cms-Bao II is mildly infected with race 0, but highly resistant to race T, quite resistant to race C. Resistance of CMS lines and its maintainer is the same (see Table 2).
Table 2. Evaluation of resistance to
southem blight disease (H. maydis).
|Race O||Race C||Race T|
|No.of line||Disease degree||Disease state coefficent||Resistance||Disease degree||Disease state coefficent||Resistance||Disease degree||Disease state coefficent||Resistance|
|Zhongdan 2(cms-Bao I)||0.5||12.22||H.R||0||0||Q.R||0.5||10.5||H.R|
Notes: R…Resistance; H.R…High resistance;
S…susceptivity; m.s…mid-susceptivity; Q.R…Quite resistant.
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