If pollen grains of anther of plant1 come on stigma of another plant2 of another type will fertilisation occur? If after that pollen grains of flower3 same to flower2 with stigma come on stigma of flower2 the nutrients secreted stigma will absorbed.by which pollen grain .Explain more in detail if necessary.

Dear student,
The pollen grain of flower 1 landing over stigma of flower 2 will lead to fertilisation if the are of the same species due to incompatibility other species pollen can not cause fertilisation. If both the pollen grain of flower 3 and flower 1 lands on stigma of flower 2 then the pollen belonging to the same species will absorb nutrient and grow while pollen grain belonging to other species will not grow due to incompatibility.

Regards