Control methods of asparagus stem blight

Asparagus is a kind of stem vegetable which is often eaten by people. However, stem blight in the planting process will lead to serious yield reduction. Stem blight is also called asparagus cancer, which will reduce yield in light or lose harvest in heavy, which will bring great losses to the majority of growers. So how to prevent asparagus stem blight? Let's take a look at it together with Xiaobian.

I. Symptoms

Asparagus stem blight is caused by the pathogen infecting tender stems and tender shoots. After infection, the disease spots of needle-like milky white needle spots are initially formed on the infected site, gradually expanding into spindle or fusiform small spots, and the disease spots will gradually turn brown, with gray brown center, depression and scattered small black spots, i.e. conidia. When the disease spots are severe, the whole plant will grow, and when the disease spots around the stem for a week, the whole plant will dry up and die.

II. Rules of occurrence

In cold winter, the aboveground part of asparagus dies, and the pathogen overwinters in the form of hyphae and conidia. In spring, when the temperature and humidity are suitable, conidia are produced from conidia for primary infection. In greenhouse cultivation, asparagus grows all the year round, which also provides favorable conditions for asparagus stem blight. There is no overwintering dormancy and initial infection, and multiple infection cycles can be carried out all the year round.

III. Prevention and control methods

1. Select resistant varieties

The prevention and control of stem blight should start from the source. Before seedling, seed disinfection should be carried out to prevent stem blight pathogen. Preventive measures should be taken during seedling management. To regular observation, every half month on the spraying of carbendazim and mancozeb for a preventive chemical control, but also to control aphids, thrips, moths and other larvae.

2. Do a good job in clearing the garden

The key link of asparagus disease prevention in winter is whether the garden is cleaned timely and thoroughly, which determines the incidence of stem blight in the next year. The best way to prevent stem blight is to reduce the base of pathogenic bacteria, and the method to reduce the base of pathogenic bacteria is to clean the garden.

3. Shelter cultivation

The most effective way to control asparagus stem blight during greenhouse cultivation is to adopt greenhouse cultivation, which can prevent rainwater from entering the shed and block the transmission route during the period; secondly, it can regulate the temperature to prevent premature aging of plants and improve immunity; thirdly, fumigant can be used to greatly reduce manpower, material resources and financial resources; fourth, it can obviously prolong the picking period and increase the yield.

4. Chemical control

The fungicides that can control stem blight mainly include carbendazim, mancozeb, chlorothalonil, bordeaux mixture, etc. In order to avoid the occurrence of drug resistance, different fungicides should be used alternately.

The above is an introduction to the control methods of asparagus stem blight. I hope it can help you. If you want to know more about it, please pay attention to us.