Diseases and pests of popular indoor potted flower crops

Some indoor crops are particularly susceptible to leaf wart (pathogen — Corynebacterium fascians). The disease manifests as green nodules up to 1—2 cm in diameter. The affected plant becomes deformed and unsuitable for sale. The infection spreads easily during the care of plantings and the selection of cuttings from diseased stock plants.

On campanula, root and basal rots, caused by Pythium and Phytophthora species, represent a serious problem. They lead to wilting and plant death, and in cases of mild infestation, to stunted growth. The development of campanula is also negatively affected by the pathogen Verticillium dahliae. In addition, the crop can be affected by stem rot (pathogen — Sclerotinia sclerotiorum) and grey mold on stems, leaves, and flowers (Botrytis cinerea).

Chlorophytum is characterized by similar problems with the root system. One of the Pythium species causes root rot in it. In this case, grey mold (Botrytis cinerea) often settles on the affected tissues of leaves and stems as a secondary parasite.

1. Grow healthy stock plants to prevent the introduction of infection.
2. Use only pathogen-free compost for planting.

Specifics of cineraria protection against diseases and physiological stresses

Cineraria is a popular potted crop, susceptible to many diseases, including non-pathogenic wilting. It develops due to a mismatch between the leaf surface area and the root volume during any disruption of the water regime. For normal growth, cineraria requires constant, but not excessive, transpiration of water by the leaves. Creating such conditions at home is rarely successful, which is why the crop is difficult to grow outside specialized greenhouses.

In greenhouses, cineraria is often affected by Pythium and Phytophthora species, which cause root and basal rots. The complex of pathogens also includes the causal agents Sclerotinia sclerotiorum, Thielaviopsis basicola, and grey mold (Botrytis cinerea). Sometimes, powdery mildew (Sphaerotheca fuliginea) appears on the leaves, although there is no data on its cross-transmission to cucumber yet. Bacterial leaf wart (Corynebacterium fascians) causes deformation of stems and leaf axils but does not cause significant damage to the crop.

Cineraria rust is caused by the fungi Coleosporium tussilaginis and Puccinia lagenophorae, which form orange pustules on the underside of leaves. Their spores are dispersed by air and germinate in water droplets or under high humidity. Intermediate hosts for these fungi are coltsfoot (Tussilago farfara) and groundsel (Senecio vulgaris). Regular spraying with fungicides is effective for rust control.

Downy mildew (pathogen Bremia lactucae) is the most dangerous pathogen for cineraria. It manifests as yellow spotting on the upper side of the leaves and a white fuzzy coating on the underside. The fungus spores are dispersed by wind and germinate under high humidity, especially at temperatures above 15 °C. Although Bremia lactucae also affects lettuce, cross-infection between the crops has not been proven; protective measures are carried out by analogy with treatments on lettuce.

When cineraria is affected by leaf spot (pathogen — Alternaria senecionis), brown spots appear on the lower leaves. A humid environment promotes the development of the disease. Coarse-droplet spraying with fungicides is used to control alternariosis.

• Nodule diameter for leaf wart — up to 1—2 cm
• Germination temperature for downy mildew spores — above 15 °C
• Rust control preparations — zineb, mancozeb, benodanil, oxycarboxin
• Alternariosis control preparations — iprodione, captan