Figure 4.

Hybridization of medium and highly repetitive cloned maize DNA sequences 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) EtdBr-stained 0.8% agarose gel; lane M is a 1-kb molecular weight marker ladder. (b) The 0.7-kb EcoRI fragment of cosmid 10 shows multiple bands on different maize chromosomes as well as one common band for all chromosomes. (c) Cosmid 1, with a 40-kb insertion, shows strong hybridization signal over maize (lines m1 and m2) and over chromosome addition lines 9, 7, 4, 3, and 2; no hybridization is seen over oat DNA (lines o1 and o2). (d) With the 185-bp knob repeat, most of the hybridization signal is located on chromosome 9. No hybridization to oat DNA is detected.