What are the common pests and diseases of colored calla lilies?
The common diseases of colored calla lilies mainly include bacterial diseases, fungal diseases and pest infestations, which are introduced separately below. Bacterial diseases Erwinia: Erwinia disease, also known as soft rot, is caused by Pectobacterium carotovorum subsp. carotovorum. Infected leaves and stems turn dark green, with necrotic spots and rot spots...
The common diseases of colored calla lilies mainly include bacterial diseases, fungal diseases and pest infestations, which are introduced separately below. Bacterial diseases Erwinia: Erwinia disease, also known as soft rot, is caused by Pectobacterium carotovorum subsp. carotovorum. Infected leaves and stems turn dark green, with necrotic spots and rot spots, and secrete mucus, and eventually the plant collapses. The tubers also begin to rot and give off a foul odor. When the plant grows poorly, infection can occur through small wounds. These bacteria can also secrete some enzymes to dissolve cell walls and penetrate the plant. If the plant is dry, the infected plant and the soil it grows in should be carefully removed. Note that before planting, those infected tubers should be picked out as early as possible and disinfected as a preventive measure. The sensitivity to Erwinia infection also varies with different cultivars. Generally speaking, yellow and orange cultivars are more susceptible to infection than white and cream-colored cultivars. The best control method is to provide the plant with an optimal growing environment from beginning to end during cultivation, so that it can develop without interference. The growing environment for colored calla lilies should meet the following requirements:?
Provide sufficient moisture (do not plant too shallowly; water again when the soil dries out);
The soil should have good drainage to prevent waterlogging;
Avoid excessively high temperatures in the greenhouse, especially when relative humidity is high;
Prevent damage to plants and tubers (prevent wind damage to plants, take care not to let herbicides affect plant growth, and handle carefully during harvest and handling);
Prevent damage caused by other fungal diseases and pests. (For example, damage caused by Pythium or Rhizoctonia may provide an entry point for Erwinia);
Do not use too much nitrogen fertilizer, because a nitrogen application rate of more than 150 kg per hectare can easily cause Erwinia infection.
Tubers should be dried as soon as possible after harvest: any delay within the first week after harvest will cause large losses later. Fungal diseases Pythium: This fungus causes root rot
rot, which restricts the plant's water uptake. Crop rotation and precise irrigation (as well as drainage) are important factors in preventing infection. Steam-sterilize the soil before planting and treat it with fungicides.
Rhizoctonia: This fungus damages the plant's shoots near the soil surface. Tolclofos-methyl and flutolanil can be used to treat the soil to control this fungus.
Penicillium: This fungus can cause infection during tuber storage, causing damage to tubers during and after storage, especially when tubers have suffered mechanical damage, when the storage room's relative humidity is too high, or when air circulation in the microenvironment is insufficient. Providing sufficient air circulation can prevent this pathogen. Fungicides such as captan can also be used to disinfect tubers.
Botrytis: It can occur on flowers and leaves. During open-air cultivation, preventive treatment combining fungicides and insecticides every 10 days is necessary. Botrytis infection almost always appears as small spots on the leaves. A single preventive spray at the end of August or the beginning of September is already sufficient. Pests Thrips and aphids during the entire growth
process will cause damage. Before flower harvesting, use parathion