Fig. 4

Selection of leaf tissue for protoplast isolation. Barley and wheat plants are grown to a size of 9–15 cm from base to tip. Growth stage 1 represents cultivars (cv.) that reach this seedling size by growing a long first leaf (e.g. barley cv. Manchuria, wheat cv. Svevo and cv. Fielder). Growth stage 2 represents cultivars that reach this seedling size by growing a short first leaf and a second leaf (e.g. barley cv. Golden Promise). Arrow indicates the leaf optimal for mesophyll protoplast isolation of second leaf stage cultivars. Brackets indicate the respective leaf region to be selected for isolation of mesophyll protoplasts