Growing a nursery of crop seedlings then transplanting them at the appropriate time is a facet of which agricultural technique? paddy

rice cultivation.

Explanation:

There are two methods of sowing a crop in the field i. e. sowing of seed and transplanting. Seeds sowing in the field is used for almost all the crops except rice in which transplantation is done. In transplanting method, plants are grown inside a nursery and when the plant reaches to a certain height, it is transported to the field. This method is done in the cultivation of paddy rice because water is present at a certain height in the field and rice is the only crop in which roots respire in water.