Figure 3.

Hybridization of unique and low-copy-number DNA sequences isolated from maize-specific cosmids shown in Fig. 2 to a blot panel of oat–maize chromosome addition lines carrying maize chromosomes 9, 7, 4, 3, and 2, respectively; m1 and m2 are maize stocks A188 and Seneca 60; o1 and o2 are oat stocks Sun II and Starter-1. (a) The 2.5-kb EcoRI fragment from cosmid 15 shows one band on the chromosome 9 addition line. An additional polymorphic band is present in the parental stocks of maize. (b) The 1.8-kb EcoRI fragment from cosmid 28 detects two bands. One band, polymorphic between m1 and m2, is present in the chromosome 9 addition line. An additional nonpolymorphic band is present on chromosome 9 and in both parental stocks. (c) The 2.1-kb EcoRI fragment from cosmid 10 shows one band on chromosome 9. (d) The 1.4-kb EcoRI fragment from cosmid 20 detects about 20 bands in parental maize stocks and several bands among the chromosome addition lines. The band pattern is chromosome-specific. No cross-hybridization occurred to oat DNA in a–d. (e) The 2.9-kb EcoRI fragment from cosmid 6 detects several polymorphic bands in parental maize stocks. One nonpolymorphic band is seen in maize, oat, and chromosomes 9, 7, 4, and 2 addition lines. Additional bands are seen in other chromosome addition lines.