There was an association of agriculture and sedentary society. There was an association with cooking and with other detoxification of plants. Cooking made many plants more usable by man. Cooking arose before agriculture. Many hunter-gatherer societies know all they need to know about growing plants, but don't.
Some gatherers do plant seeds.
Some gatherers replant parts of root crops. Most cultures based on seeds, not root crops. Many root crops important in the lowland tropics. Some gatherers also irrigate. Gatherers learned how to cook and to detoxify foods in many cases.