From which plant were haploid plants first obtained through anther culture?

The reason for the formation of an embryoid from a pollen grain in a tissue culture medium is:

In tissue culture experiments using tobacco callus,it was observed that when the culture medium contains $2 \ ppm$ of $IAA$ and $2 \ ppm$ of kinetin,an undifferentiated mass of callus is produced. If the ratio of kinetin to $IAA$ is increased,what will happen?

Which of the following plant parts is used as an explant to prepare virus-free plants?

For which purpose are plants developed through the plant tissue culture method used?

Haploid plants are obtained from which of the following?