Fig. 5. The phenotypic changes of the NPA-treated flowers in dioecious papaya “Zhonghuang”.

a Male inflorescences on the male plants. b Female flowers on the female plants. c Male inflorescences treated by NPA. Arrow indicated a long-rod phenotype flowers due to a decrease in androecium number. d A long-rod phenotype male flower with only one androecium. Arrow indicated the rudimentary gynoecium. Bar = 2 mm. e A long-rod phenotype male flower with no trace of filaments and anthers. Arrow indicated the rudimentary gynoecium. Bar = 2 mm (f) Normal male flower. Arrow indicated the rudimentary gynoecium. Bar = 2 mm. g Phenotypically similar perfect hermaphrodite flowers with fertile gynoecium in male plant. Gynoecium-like structures (gyn-like) bore flat and smooth stigmas(left), bore feathery stigmas (mid), and entirely embedded in merged outer whorls of floral system(right). All newly induced hermaphrodite flowers referred to have visible androecium(an). h,i The transformed primary male flowers surrounded with adjacent clusters of male flowers. Arrow indicated the transformed primary male flowers. j The inflorescences of Vasconcellea monica. k,l The NPA-treated female flower bore a stalk-like gynoecium with stigma. Arrow indicated the stalk-like gynoecium, Bar = 1 mm (m) Normal female flower. Arrow indicated the functional gynoecium, Bar = 1 mm