“…The doubled haploids of sunflower can be produced in vitro from an anther culture by direct embryogenesis [ 9 , 17 , 38 , 39 ], indirect embryogenesis [ 13 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 ], or indirect shoot organogenesis [ 10 , 17 , 38 , 40 , 44 , 47 , 48 , 49 , 50 , 51 , 52 ] ( Figure 1 ). Several independent research groups have reported the formation of callus tissue from anther culture without any subsequent morphogenic response ( Table 1 and Table 2 ) [ 9 , 17 , 30 , 41 , 42 , 43 , 44 , 47 , 48 , 49 , 50 , 53 ].…”