Hyacinth Pest and Disease Control Methods and Key Knowledge Points
Knowledge on the prevention and control of hyacinth diseases and pests
Common hyacinth diseases include sprout rot, soft rot, sclerotinia rot and viral diseases. Before planting, the growing medium should be strictly sterilized, and the bulbs should be cleaned and disinfected. During the growing period, spray once every 7 days with a 1000-fold dilution of Tuijunte or chlorothalonil, alternating between them, which can inhibit the spread of pathogens to a certain extent. Strictly control the amount of watering, strengthen ventilation management, control the relative air humidity in the environment, and promptly remove any centrally diseased plants, which can greatly reduce the disease incidence.
To prevent disease occurrence during outdoor soil cold treatment, a advisable method is to use fresh soil every year. In this way, there is no need to carry out routine soil treatment.
If the soil has been used before, it can still be used for potting or covering the bulbs. Before use, routine soil sterilization is recommended to avoid the occurrence of Rhizoctonia. This routine soil treatment method is consistent with the soil treatment before planting tulips. In addition, you may refer to relevant methods for routine soil treatment; we suggest that you consult your local relevant authorities.
If hyacinth bulbs are provided with a temperature of 9°C immediately after planting, and during cold treatment the flower buds are fully exposed without soil covering, there is no need to use fungicides to treat the bulbs.
Parasitic top rot
When part of the plant located above the inflorescence has rotting flowers, it is called "top rot," and it is often accompanied by brown spots appearing at the leaf tips. This kind of rot is mostly caused by parasites that are randomly present under normal conditions, including plants that begin to be infected only after the florets have dried out (physiological bud rot) or plants that have already been infected in advance by parasitic fungi (parasitic fungal bud rot), after which the parasites can cause the initial infection.
Rhizoctonia
This fungus begins infecting the plant from contaminated soil (even contaminated before planting). The identifying sign is irregularly shaped, bright brown jagged scars on some florets. The occurrence on the outer leaves is slightly milder. In more severe infections, the spots become larger, the plant leaf tips turn brown, and under greenhouse cultivation a spiderweb-like trace of fungal growth can be seen. This infection often appears in patches, and the infection intensifies when the soil temperature rises.
Prevention methods: Frequently use new soil as potting soil. Contaminated soil should be treated by routine methods before use. Natural cold treatment and the rooting room should maintain the specified temperature.
Penicillium
This belongs to storage-period rot, and the initial symptoms can be seen immediately before planting. The part of the root tip infected by the fungus dries up. When the base of the root is cut open, the surrounding tissue can be seen to be light brown. The same color of tissue can also be seen where small bulbils have detached. During storage and subsequent planting, the bulbs will continue to rot. Infected bulbs have relatively short sprouts, and the bulbs themselves have few or no roots. The plants easily lodge.
This fungal infection also occurs on injured parts of the bulbs. On the infected parts there is white to blue-green fungal growth, and the tissue beneath becomes brown and soft, but this infection does not extend to the basal plate, and it also has no adverse effect on flowering quality.
This infection is caused by different Penicillium species such as P. verrucosum. "Pink Pearl" and its variants are easily infected through the root tips. This infection mainly occurs in low-temperature storage rooms (below 17°C), while humidity is above 70%. Another cause is injury to the bulbs.
Control methods: Prevent premature sprouting or root formation. Plant immediately after arrival (especially "Pink Pearl" and its variants). In the storage room, maintain the specified constant temperature and keep air circulating. Maintain humidity below 70% throughout the storage period.
Erwinia
Soft rot. In the greenhouse, severely infected bulbs no longer sprout. The bulbs become soft, and the bulb tissue becomes transparent and is accompanied by white or yellow spots. These infected bulbs also give off an unpleasant odor. The symptoms of less severe infection are: some wet, dark green elongated areas form from the leaf base, which first cause growth to be checked, and then the plant wilts until it dies.
This disease is caused by Erwinia bacteria. These bacteria are mostly parasitic, mainly infecting frozen or overly wet tissue. When the temperature is too high or the soil is too wet, another form of infection occurs through wounds at the places where early roots or small bulbils have detached. This problem is mainly caused by soil temperature being too high or too wet during natural cold treatment in autumn. "Delft Blue" and "Carnegie" are extremely susceptible cultivars. This disease is not contagious in the greenhouse; although infected tissue usually appears butter-yellow, the infection will not occur again in other parts.
Control methods: Bulbs are usually planted under the recommended conditions, that is, natural treatment or keeping the rooting room at low temperature (9°C), while also not too humid. During planting and throughout the greenhouse period, remove infected bulbs and plants. This can prevent Erwinia from spreading to neighboring bulbs through irrigation water.
Physiological bud rot
The last floret dehydrates, which is caused by too short a cold treatment. Sensitivity to this bud rot is determined according to different cultivars and bulb sizes.
Control methods: Ensure that the rooting room for planted bulbs and the natural treatment temperature are maintained at a constant 9°C; for treatments not at 9°C, use compensatory measures. Do not move the bulbs indoors too early; provide the cold treatment required by each cultivar. During the greenhouse period, maintain a constant 23-25°C, and during planting do not let the temperature drop by more than 1-2°C, so as to avoid Penicillium infection caused by relatively high humidity in the greenhouse climate. Never pour water onto the inflorescence, especially at the final stage. Before transport, if storage cannot be provided, do not let the soil in the pots become too wet, and at the same time ensure sufficient air circulation between plants.
Top greening
The florets at the top of some inflorescences remain green, and in severe cases this can extend over the entire top of the flower. Cause: a disorder caused by improper low-temperature treatment; too short a treatment time or incorrect temperature can both produce this result. Some cultivars, such as "Pink Pearl" and its variants and "Jan Bos," are more sensitive to this disorder than other cultivars.
Control methods: After cultivation, carry out operations according to the specified cold treatment period and low temperature.
Crooked inflorescence
After the bulbs are moved into the greenhouse, the growth at the very top of the hyacinth flower stem becomes crooked. In large hyacinth inflorescences, part of the flower stem and the florets attached to it grow relatively faster than other parts, such as in cultivars like "Delft Blue" and its variants, "Carnegie" and "L'Innocence." This trait is not what we desire, and this disorder is mostly seen in earlier plantings and in hyacinths with large inflorescences.
Control methods: After planting, use the specified cold treatment and low-temperature standards. Maintaining a slightly lower greenhouse temperature (18-17°C) can also prevent the occurrence of crooked inflorescence.
Top flowering
Unlike normal growth, the florets located at the top open earlier than those at lower positions. The inflorescences of this kind of flower are usually short and sturdy. This disorder is caused by not carrying out the cold treatment required by the cultivar before moving the plants indoors. The sensitivity of each cultivar to this disorder varies.
Control methods: After planting, operate according to the specified cold treatment and low-temperature standards.
Gray mold
In the early stage of disease onset, the tips of infected leaves change color, and the leaves shrivel and rot. Under cold and humid conditions, the flowers also rot. In the later stage of disease onset, the diseased parts produce a gray mold layer and black sclerotia. The pathogen overwinters as sclerotia in diseased residues and soil, and when conditions are suitable it produces conidia, which spread with wind and rain to cause infection and damage. Low temperature and high humidity favor disease occurrence.
Control methods
Chemical control: In the early stage of disease onset, spray with 1:1:100 Bordeaux mixture, or 65% zineb wettable powder at 500-800-fold dilution, or 50% benomyl wettable powder at 1000-fold dilution, or Banxiuqing at 800-1000-fold dilution for spray control.
Root nodule disease
Hyacinth root swelling disease is also called root nodule disease. The root system is normal when it first appears, but after extending to a certain degree it produces small white nodules, growth weakens, and sometimes dry rot of florets occurs, affecting growth and development, and in severe cases the whole plant dies.
Control methods
During storage, carry out strict disinfection and sterilization, pay attention to strengthening ventilation, check frequently, turn frequently, and promptly pick out diseased plants and burn them in a centralized manner.
Strictly carry out soil disinfection and sterilization, do not practice continuous cropping, and do not reuse cultivation soil.
During cultivation, promptly remove diseased plants when found, and carry out insect and sterilization treatment on the soil.
Strict quarantine, and do not allow diseased bulbs or diseased plants to enter the nursery.
Pests and diseases of grape hyacinth and their control
Grape hyacinth smut
Damage characteristics
Smut mainly damages the flowers of grape hyacinth, seriously affecting their ornamental appearance.
Control
Spray with 50% thiophanate wettable powder at 1000-fold dilution for control.
Grape hyacinth yellow rot
Damage characteristics
At first, lesions form near the leaf veins of the affected plant, appearing water-soaked, and afterward the lesions appear yellow or brown. In affected bulbs, the interior becomes filled with yellow mucus and then rots.
Control
Control should begin at the time of planting. Select relatively robust bulbs, disinfect them, and then plant them in the soil; formalin solution can be used for thorough disinfection. When disease occurs, spray with 50% carbendazim at 1000-fold dilution for control.
Grape hyacinth sclerotinia rot
Damage characteristics
The pathogen of sclerotinia rot mainly invades through the bulb and damages the leaves of grape hyacinth, causing yellow round spots or streak spots to appear.
Control
As with yellow rot, choose robust and disease-free bulbs for planting. Before that, the soil should be disinfected; pentachloronitrobenzene can be mixed with the potting soil, stirred evenly, and then the bulbs planted. In addition, for the plants, observe more often; once diseased plants are found, promptly pull them out, then bury them deeply or burn them, to prevent them from harming the plants again.
Overall, grape hyacinth has relatively few pests and diseases, but it still needs careful management and care; only then will it be healthier and more beautiful.
What pests and diseases do hyacinths have? Common hyacinth pests and diseases
Hyacinth is a perennial herbaceous plant in the genus Hyacinthus of the family Hyacinthaceae, and it is also one of the plants that many people like very much. Many people may have grown hyacinths at home, so how much do you know about hyacinth pests and diseases? Below, we introduce common hyacinth pests and diseases and their control methods.
1. Rhizoctonia
This fungus begins infecting the plant from contaminated soil (even contaminated before planting). The identifying sign is irregularly shaped, bright brown jagged scars on some florets. The occurrence on the outer leaves is slightly milder. In more severe infections, the spots become larger, the plant leaf tips turn brown, and under greenhouse cultivation a spiderweb-like trace of fungal growth can be seen. This infection often appears in patches, and the infection intensifies when the soil temperature rises.
Control methods: Frequently use new soil as potting soil. Contaminated soil should be treated by routine methods before use. Natural cold treatment and the rooting room should maintain the specified temperature.
2. Penicillium
This belongs to storage-period rot, and the initial symptoms can be seen immediately before planting. The part of the root tip infected by the fungus dries up. When the base of the root is cut open, the surrounding tissue can be seen to be light brown. The same color of tissue can also be seen where small bulbils have detached. During storage and subsequent planting, the bulbs will continue to rot. Infected bulbs have relatively short sprouts, and the bulbs themselves have few or no roots. The plants easily lodge.
This fungal infection also occurs on injured parts of the bulbs. On the infected parts there is white to blue-green fungal growth, and the tissue beneath becomes brown and soft, but this infection does not extend to the basal plate, and it also has no adverse effect on flowering quality.
This infection is caused by different Penicillium species such as P. verrucosum. "Pink Pearl" and its variants are easily infected through the root tips. This infection mainly occurs in low-temperature storage rooms (below 17°C), while humidity is above 70%. Another cause is injury to the bulbs.
Control methods: Prevent premature sprouting or root formation. Plant immediately after arrival (especially "Pink Pearl" and its variants). In the storage room, maintain the specified constant temperature and keep air circulating. Maintain humidity below 70% throughout the storage period.
3. Erwinia
Soft rot. In the greenhouse, severely infected bulbs no longer sprout. The bulbs become soft, and the bulb tissue becomes transparent and is accompanied by white or yellow spots. These infected bulbs also give off an unpleasant odor. The symptoms of less severe infection are: some wet, dark green elongated areas form from the leaf base, which first cause growth to be checked, and then the plant wilts until it dies.
This disease is caused by Erwinia bacteria. These bacteria are mostly parasitic, mainly infecting frozen or overly wet tissue. When the temperature is too high or the soil is too wet, another form of infection occurs through wounds at the places where early roots or small bulbils have detached. This problem is mainly caused by soil temperature being too high or too wet during natural cold treatment in autumn. "Delft Blue" and "Carnegie" are extremely susceptible cultivars. This disease is not contagious in the greenhouse; although infected tissue usually appears butter-yellow, the infection will not occur again in other parts.
Control methods: Bulbs are usually planted under the recommended conditions, that is, natural treatment or keeping the rooting room at low temperature (9°C), while also not too humid. During planting and throughout the greenhouse period, remove infected bulbs and plants. This can prevent Erwinia from spreading to neighboring bulbs through irrigation water.
4. Physiological bud rot
The last floret dehydrates, which is caused by too short a cold treatment. Sensitivity to this bud rot is determined according to different cultivars and bulb sizes.
Control methods: Ensure that the rooting room for planted bulbs and the natural treatment temperature are maintained at a constant 9°C; for treatments not at 9°C, use compensatory measures. Do not move the bulbs indoors too early; provide the cold treatment required by each cultivar. During the greenhouse period, maintain a constant 23-25°C, and during planting do not let the temperature drop by more than 1-2°C, so as to avoid Penicillium infection caused by relatively high humidity in the greenhouse climate. Never pour water onto the inflorescence, especially at the final stage. Before transport, if storage cannot be provided, do not let the soil in the pots become too wet, and at the same time ensure sufficient air circulation between plants.
5. Top greening
The florets at the top of some inflorescences remain green, and in severe cases this can extend over the entire top of the flower. Cause: a disorder caused by improper low-temperature treatment; too short a treatment time or incorrect temperature can both produce this result. Some cultivars, such as "Pink Pearl" and its variants and "Jan Bos," are more sensitive to this disorder than other cultivars.
Control methods: After cultivation, carry out operations according to the specified cold treatment period and low temperature.
6. Crooked inflorescence
After the bulbs are moved into the greenhouse, the growth at the very top of the hyacinth flower stem becomes crooked. In large hyacinth inflorescences, part of the flower stem and the florets attached to it grow relatively faster than other parts, such as in cultivars like "Delft Blue" and its variants, "Carnegie" and "L'Innocence." This trait is not what we desire, and this disorder is mostly seen in earlier plantings and in hyacinths with large inflorescences.
Control methods: After planting, use the specified cold treatment and low-temperature standards. Maintaining a slightly lower greenhouse temperature (18-17°C) can also prevent the occurrence of crooked inflorescence.
7. Top flowering
Unlike normal growth, the florets located at the top open earlier than those at lower positions. The inflorescences of this kind of flower are usually short and sturdy. This disorder is caused by not carrying out the cold treatment required by the cultivar before moving the plants indoors. The sensitivity of each cultivar to this disorder varies.
Control methods: After planting, operate according to the specified cold treatment and low-temperature standards.
8. Gray mold
In the early stage of disease onset, the tips of infected leaves change color, and the leaves shrivel and rot. Under cold and humid conditions, the flowers also rot. In the later stage of disease onset, the diseased parts produce a gray mold layer and black sclerotia. The pathogen overwinters as sclerotia in diseased residues and soil, and when conditions are suitable it produces conidia, which spread with wind and rain to cause infection and damage. Low temperature and high humidity favor disease occurrence.
Control methods: Reduce sources of infection: promptly remove diseased flowers and leaves and destroy them in a centralized manner. Chemical control: In the early stage of disease onset, spray with 1:1:100 Bordeaux mixture, or 65% zineb wettable powder at 500-800-fold dilution, or 50% benomyl wettable powder at 1000-fold dilution, or Banxiuqing at 800-****-fold dilution for spray control.
9. Root nodule disease
Hyacinth root swelling disease is also called root nodule disease. The root system is normal when it first appears, but after extending to a certain degree it produces small white nodules, growth weakens, and sometimes dry rot of florets occurs, affecting growth and development, and in severe cases the whole plant dies.
Control methods: During storage, carry out strict disinfection and sterilization, pay attention to strengthening ventilation, check frequently, turn frequently, and promptly pick out diseased plants and burn them in a centralized manner. Strictly carry out soil disinfection and sterilization, do not practice continuous cropping, and do not reuse cultivation soil. During cultivation, promptly remove diseased plants when found, and carry out insect and sterilization treatment on the soil. Strict quarantine, and do not allow diseased bulbs or diseased plants to enter the nursery.
The above is an introduction to common hyacinth pests and diseases and their control methods. We hope it can help everyone. For more home knowledge, please stay tuned.