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 damage, which are introduced separately below. Bacterial disease Erwinia: Erwinia disease, also known as soft rot, is caused by the pv. carotovora pathovar of Pectobacterium carotovorum subsp. carotovorum. Infected leaves and stems turn dark green, with necrotic spots and rotting spots...
The common diseases of colored calla lilies mainly include bacterial diseases, fungal diseases and pest damage, which are introduced separately below. Bacterial disease Erwinia: Erwinia disease, also known as soft rot
rot, is caused by the pv. carotovora pathovar of Pectobacterium carotovorum subsp. carotovorum. Infected leaves and stems turn dark green, with necrotic spots and rotting 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 in which it grows should be carefully removed. Care should be taken to pick out those infected tubers as early as possible before planting, and to disinfect them for prevention. The degree of susceptibility to Erwinia infection also varies among varieties. Generally speaking, yellow and orange varieties are more susceptible than white and cream-colored varieties. The best control method is to provide the plant with an optimal growing environment throughout cultivation, so that it can develop without interference. The growing environment for colored calla lilies should meet the following requirements:?
Provide sufficient water (do not plant too shallowly; water again when the soil dries out);
The soil should have good drainage to prevent excessively wet conditions;
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 disease Pythium: This fungus causes root rot
rot, causing the plant's water absorption to be restricted. 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 causes damage to the plant's shoots near the ground. 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 relative humidity of the storage room is too high, or when air circulation in the micro-environment is insufficient. Providing sufficient air circulation can prevent the occurrence of this pathogen. Fungicides can also be used to disinfect tubers, such as captan.
Botrytis: Can occur on flowers and leaves. When grown in the open air, combined preventive treatment with fungicides and insecticides every 10 days is necessary. Botrytis infection on leaves almost always appears as small spots. At the end of August or the beginning of September, a single application is enough for prevention. Pests Thrips and aphids can cause damage throughout the entire growth
process of the plant. Spray twice with parathion before flower harvesting, and during cultivation, acephate or deltamethrin can be used every 7-10 days for prevention.