••••••Gregor Johann Mendel formulated the basic rule of inheritance of traits . He was working on Garden pea plant ( pisum sativum ) and studied the inheritance of contrasting characters like round/wrinkled seeds , tall/short plants , white/ violet flowers and so on. He investigated the inheritance of a single contrasting trait which resulted in the monohybrid inheritance .•••••

••••Monohybrid inheritance = MENDEL Crossed true breeding tall and dwarf plants . All the plants in F1 generation were tall and when he crossed the first generation progeny among themselves it resulted in F2 generation .The resulted progeny consisted of both tall and dwarf plants in the ratio of 3 ( tall) : 1( dwarf)••••• .

•••••Dihybrid inheritance = in this experiment he crossed pure breeding pea plants having round seeds with yellow cotyledons and wrinkled seeds with green cotyledons . As a result pea plants in F1 generation were round yellow and on crossing F1 generation among themselves he found F2 generation with different characters like round- yellow , round - green , wrinkled - yellow and wrinkled- green seeds in the ratio of 9:3:3:1 . ••••