Flower induction by atrazine analogues in seedlings of Asparagus officinalis

Flower formation in one-month-old seedlings of asparagus (Asparagus officinalis L. cv. Mary Washington 500 W) was increased by soaking the seeds for 12 days in solutions of an atrazine analogue. These compounds are known to affect electron flow in photosystem II. Whereas only 2.4% of the control seedlings flowered, one of the fourteen analogues tested caused 60% of the seedlings to flower at 400 μM. These seedlings continued to grow normally and produced new shoots, but these had no flowers. Flowers formed only at the shoot tip and were morphologically normal. Treatment with an atrazine analogue enables sex identification of the plants at an early stage.