table transformation before ANOVA

data_new = pd.melt(data.reset_index(), id_vars=['index'], value_vars=['A','B','C'])
data_new.columns=['index','treatments','value']

Two-Way ANOVA
# you do not need to reshape if your data is already in stacked format.
d_melt = pd.melt(data, id_vars=['Genotype'], value_vars=['1_year', '2_year', '3_year'])
# replace column names
d_melt.columns = ['Genotype', 'years', 'value']
d_melt.head()