What are the common pests and diseases of asparagus?
Asparagus is a fairly common vegetable and is grown quite widely in China, which is also the world's largest grower of asparagus. Some pest problems are unavoidable with asparagus. Let's take a look with Qinnong Wang at which diseases are relatively common and how to deal with them when they occur.
1. Brown spot disease
Brown spot disease is one of the more harmful conditions affecting asparagus and is also a frequently occurring disease, with the affected areas mostly concentrated on the stems. When the disease strikes, brown spots first appear on the stems; the color tends toward yellow in summer and toward black in winter, and the spots then gradually spread and merge together, causing the whole plant to turn yellowish-brown until it withers. 50% anilazine wettable powder at 500 times dilution or 50% folpet at 800 times dilution both have a good effect on controlling brown spot disease.
2. Stem rot
Stem rot occurs mostly on young spears, mainly during the rainy season, and is usually triggered by excessive humidity. In the early stage, water-soaked marks gradually appear on the young spears; by this time the parts that have just emerged have in fact already begun to rot, and white thread-like mold spots slowly appear on the emerged parts. If not handled properly, it will spread the disease on a large scale. It is recommended to use 64% oxadixyl wettable powder at 500 times dilution for control, and soil disinfection must be done well at the early stage of planting.
3. Insects such as owlet moths
The harm these insects do to asparagus is considerable once they appear, and they are highly destructive pests. Their main target is the more tender parts, which they chew on directly once found, and they mostly appear in summer. When these visible insects are found on asparagus, they must be dealt with promptly, otherwise they will seriously harm the growth and development of the asparagus. You can use 90% trichlorfon crystals at 1000 times dilution; this is currently one of the relatively better agents for treatment.
4. Parasitic pests such as aphids
The severity of pests such as aphids is mostly concentrated in the later stage; in the early stage they attach to relatively shady places and are hard to spot unless you look carefully, and once they reach the later stage they cause damage in batches. The symptoms are yellowing of the plants, and the affected plants grow noticeably more slowly than normal, so the shaded areas need to be checked more often. 25% jule mixture at 2000 times dilution is a fairly effective agent for suppressing this type of pest, and after an outbreak the removed weeds should be promptly taken out of the growing area.
The above are some of the more common methods for controlling pests and diseases of asparagus. With such diseases, you should not take the attitude that only a small number have appeared and the plants can recover on their own, as this can easily lead to major economic losses later on. Once discovered, do not take chances; deal with it directly.