Cultivation techniques of aster

root rot

It mainly harms the stem base and reed head of plants. At the early stage of the disease, the roots and rhizomes were partially browned and rotted, and brown spindle-shaped lesions were produced at the base of the petiole, and gradually the leaves died and the rhizomes rotted. Prevention and control methods: Spraying 50% carbendazim wettable powder l 1000 times or 50% thiophanate-methyl wettable powder L 1000 times at the initial stage of the disease for prevention and control.

black spot

At the beginning of the disease, purple-black spots appeared on the leaves, and then they expanded into nearly round dark brown spots. Prevention and control methods: At the initial stage of the disease, spray 500 times of 65% zineb wettable powder or 50% thiophanate-methyl wettable powder 1000 times for prevention and control, and spray 1 time every 7 days for 3 times.

Spodoptera argentea

Larvae bite leaves, causing holes or nicks. Control method: spray 90% trichlorfon crystal 1000 times solution to kill.