Q. 3 Enlist the steps of controlled cross-pollination. Would emasculation be needed in a cucurbit plant? Give reasons for your answer.

Steps of controlled cross-pollination are

i.  Selection of parents with desired characters.

ii.  Emasculation, i.e., if the female parent bears bisexual flowers before dehiscence another should be removed by forceps.

iii.  Bagging, i.e., emasculated flowers have to be covered with a bag of suitable size, generally made up of butter paper, to prevent contamination of its stigma with unwanted pollen.

iv.  When the stigma of bagged flowers attains reactivity, mature pollen grains collected from anthers of the male parent are dusted in the stigma

v.  The flowers are rebagged and the fruits are allowed to develop.

Emasculation is not always needed in a cucurbit plant. Emasculation is essential only in case of bisexual flowers to prevent self-pollination. In the case of the cucurbit plant, female parent produces usually unisexual flowers but may sometimes have bisexual flowers.