Key Points for Pest and Disease Control in Understory Cultivation of Asarum

1. Diseases

Asarum sclerotinia rot is a devastating disease of cultivated Asarum, affecting the roots, overwintering buds, stems, leaves, flowers, fruits and other parts of the plant. It occurs mostly in spring and autumn, and in severe cases can cause the complete death of Asarum.

Control measures: follow the principle of "prevention is more important than cure" and make proper arrangements. (1) Block off affected areas. Prohibit the transport of diseased seeds and diseased seedlings to the outside to prevent human-mediated spread. Affected areas and seedbeds should be thoroughly treated in a timely manner. (2) Establish disease-free seedling bases. Select disease-free seedlings for transplanting, establish strict management systems, and prevent diseased soil, diseased seedlings and diseased plants from being brought into disease-free areas; strictly prohibit the shared use of tools from affected areas. (3) Seedling disinfection. Select robust seedlings when transplanting. Before transplanting, soak the seedlings for 2-4 hours in a mixture of 800-fold amobam and 200-fold 10% carbendazim, then plant them out. (4) Chemical control. For Asarum fields with a central disease focus, use a mixed preparation of amobam plus carbendazim (prepared as above), open furrows and pour it in concentrated form, reaching down to the roots; apply a total of 6 times from early April to late May and from early September to early November.

2. Insect pests

Asarum insect pests include cutworms, white grubs, locusts, black hairy caterpillars and ants. Black hairy caterpillars and locusts bite and feed on the leaves, cutworms bite through the leaf stalks, white grubs feed on the buds, roots and leaf stalks, and ants mainly carry off the seeds after the fruits mature and split open. For locusts, black hairy caterpillars and ants, a 1000-fold solution of trichlorfon can be sprayed on the leaf surfaces and the ground to kill them. For cutworms and white grubs, a 1000-fold solution of trichlorfon can be used to drench the roots, or they can be caught by hand or trapped and killed with poisoned bait.