Occurrence and Control Methods of Bacterial Soft Rot in Clivia and Diseases of Edible Fungi

Clivia has an elegant and exquisite appearance and is deeply loved by literati both in ancient and modern times, in China and abroad. Clivia is a relatively easy plant to keep alive, but it is inevitably prone to "getting sick." Below are the occurrence and control methods for bacterial soft rot in Clivia.

Symptoms: Bacterial soft rot in Clivia mostly occurs on the middle and lower leaves. The lesions initially appear as yellow-green water-soaked and translucent, then turn brown and soft-rotted; the lesions are irregular, with a distinct boundary between diseased and healthy tissue. Bacterial ooze flows out from wounds at the lesion margins; in the later stage the lesions dry up and sunken, and in severe cases the entire leaf drops off.

Occurrence pattern: The pathogen of bacterial soft rot in Clivia is the black rot pathogen subspecies of the bacterium Erwinia carotovora subsp. atroseptica (soft rot Erwinia). The pathogen overwinters on diseased host residues and plant debris, and mostly infects and causes damage through wounds; it occurs more severely under high temperature and high humidity and when there is damage by scale insects.

Control methods: 1. Control soil moisture, improve ventilation and lower the temperature, control scale insects, and reduce mechanical wounds; 2. After disease onset, spray with 15% agricultural streptomycin wettable powder at 500 times dilution or 20% thiacloprid (Longkejun) wettable powder at 600 times dilution for control, once a week, for 2-3 consecutive sprays.