Beware of flower rot!

one. Symptoms: 24 hours after infection, any part of the petal and calyx produces small translucent water stains that turn brown with the spot, and sometimes there is a light pink circle around the spot. The number of spots on each flower does not wait, but as soon as the flowers begin to wither, the spots will increase, and careful examination will find fluffy growth on the flowers, which are the hyphae and spores of Botrytis cinerea.

two. Characteristics of the disease: most of orchid flower rot produces conidia in rotten flowers, many conidia are produced from rotten flowers, when the air is cold and cool (7-18C), or the orchid room is poorly ventilated, flowers are often attacked by flower rot, which leads to the prevalence of the disease. The conidia of the pathogen are transmitted by water or air. The rapid growth of leaves after fertilization is beneficial to the occurrence of the disease under wet and cold conditions.

three. Prevention and control methods: (1) pay attention to ventilation in the orchid room, watering must be careful not to water the flowers, if watering from the top, it should be carried out in the morning to make the leaves dry as quickly as possible. (2) to remove and destroy all diseased flowers and their infectious parts, chlorothalonil, 180g, 100L, 100L, 30g/100L, manganic 192g/100L and carbendazim can be used. In addition, the application of 50% wettable powder has a good effect of 1000 times the concentration and is sprayed every 30 days. If flower rot has become a problem, spray the flower before flowering and apply benzoate according to the above ratio 7 days later, but it may leave a faint visible stain on colored flowers.

You can also use 58% metalaxyl manganese zinc (manganese zinc mindale) wettable powder 600 times, and apply 5% metalaxyl granule on the surface of the cultivation medium.