A Detailed Guide to the Prevention and Control of Flower Nematode Disease

Flower nematode disease is a disease that many flowers are now quite susceptible to, mainly affecting plants in the Asteraceae, Primulaceae, Rosaceae, Balsaminaceae and Begoniaceae families. Because nematode disease occurs in different regions and on different flowers, it often produces different symptoms, so doing a good job of prevention is very important.

Impatiens

1. Strengthen quarantine: for newly introduced flower varieties, they must pass inspection by a quarantine agency and then be isolated and trial-planted at a designated location.

2. Use disease-free strong seedlings: choose disease-free land to establish a disease-free seedling nursery, and use disease-free strong seedlings for planting.

3. Do a good job of cleaning and sanitation in the flower farm and nursery: remove dead flowers as well as weeds and miscellaneous trees inside and outside the nursery.

4. Use clean water: irrigate with groundwater, improve drainage facilities, and prevent external polluted water from flowing into the flower farm and nursery.

5. Do a good job of disinfecting seedlings and growing media.

(1) Seedling disinfection: before seedlings are potted, they can be soaked at the roots for 30 minutes in a 30-fold dilution of 3% carbofuran granules (furadan) (carbofuran is highly toxic, so pay attention to safety when using it).

(2) Growing medium disinfection: 20 days before potting, put the growing medium into a steamer, add water until it is completely submerged, then steam until the water is gone, take it out and apply a 50-fold dilution of 35% metham sodium aqueous solution, and cover with black plastic film for fumigation. Before using the growing medium, uncover the black plastic film and let it air for 7-10 days before use.

6. Disinfect finished flowers: apply 3% milor granules (fenamiphos) once every 30 days for control, at a dosage of 6-9 grams per sq m, applied in a pinwheel-shaped arrangement of holes.

7. Sterilize the ground by covering it with black plastic film: before planting, apply 3-4 kg per mu of 35% xianke aqueous solution for ground disinfection, then cover with black plastic film for 3-5 months; the control effect is quite obvious.

8. Use rolling cultivation racks: adopting off-ground and hard-surfaced planting methods can effectively prevent the spread and occurrence of nematodes and other pests and diseases.

What is flower nematode disease? How do you prevent and control flower nematode disease? What measures are taken?

Just as May begins, it always drizzles lightly; the cold of early spring is gone, and it is neither too warm nor too cool, which is especially lovely. Recently quite a few flower friends have asked me what flower nematode disease is, how to prevent it, and what measures are taken. Today I will take everyone's questions and explore this together in depth.

What is flower nematode disease?

Nematodes are lower animals, most with slender bodies and pointed or bluntly rounded heads and tails; adults are generally 0.3-1.0 mm long. In a few species the adult females are plump and spherical or pear-shaped. Plant nematodes mainly harm flowers in the Asteraceae, Primulaceae, Rosaceae, Balsaminaceae and Begoniaceae families. Diseases caused by nematodes invading flower plants are called nematode diseases. A common symptom of nematode disease is growths of varying sizes on the main and lateral roots. When the damage is severe, the fine roots rot and the leaves turn yellow and die.

How do you prevent and control flower nematode disease?

Symptoms Plant nematodes mainly harm flowers in the Asteraceae, Primulaceae, Rosaceae, Balsaminaceae and Begoniaceae families. This disease harms roots, leaves, flower buds and flowers. There are mainly two types of symptoms:

1. Aboveground symptoms:

In this type of symptom, with root-lesion nematodes, the leaves show polygonal necrotic spots and the buds are deformed, and the whole plant is dwarfed; it harms chrysanthemums, dahlias, early small chrysanthemums and so on, with the nematode body attacking leaves and buds. With stem nematodes, the symptoms are leaf deformation and flower dwarfing, and the plants may even fail to bloom. It harms tulips, hyacinths, gladioli, narcissi and so on, with the nematode body attacking corms and tubers.

2. Root symptoms:

The roots swell and become deformed in a chicken-claw shape, and the root tissue turns black and rots, as when harming tree peonies, herbaceous peonies, wax begonias, Chinese roses, impatiens, cyclamens and so on, with the nematode body attacking the plant root system. Some roots also produce spherical root knots.

Occurrence characteristics

In different regions and on different flowers, nematodes have a different number of generations per year, generally several generations to more than 10 generations, and they overwinter as eggs, larvae and adults in diseased plants and soil. The nematode bodies spread via rain, irrigation, tools, soil, flower seedlings, seed bulbs and so on. After the soil temperature rises in spring of the following year, the eggs hatch and the larvae invade through stomata, lenticels, wounds and other places. When the soil temperature is 15-30°C, it is favorable for the development and infection of root-knot nematodes and stem nematodes. Under suitable conditions, one generation can be completed in 20-30 days. Generally, sandy soil has severe incidence. Some nematodes can also transmit viruses. From spring to autumn, the population size shows an increasing trend, and the population structure develops in a diversified way.

How to prevent and control flower nematode disease

   Root-knot nematode disease This disease is widely distributed and causes severe damage. Besides harming tree peonies, it also harms more than 30 kinds of flowers such as herbaceous peonies, Chinese roses, scarlet sage, Kalimeris, cineraria, impatiens and cyclamens. Symptoms of affected flowers: the fibrous roots have strings of round root knots of different sizes. The aboveground plant appears dwarfed and grows weakly, affecting flowering. The tips and edges of the leaves shrink and turn yellow, and the leaves fall early. Control: use 1-2 grams of 10% fenamiphos granules, and bury them evenly in the potting soil; if the flower pot is large, the dosage can be increased by about 1 gram.

   Leaf nematode disease This disease often harms chrysanthemums, and also harms dahlias, Chloranthus, calceolarias, cornflowers, gladioli and oleanders and so on. Symptoms of affected flowers: in the early stage of damage there are light yellowish-brown spots on the leaves, which later expand into brown patches. Diseased plants, diseased residues and diseased soil should be removed in time. Mix 1-2 grams of 3% furadan granules evenly with an appropriate amount of fine soil and sprinkle it into the potting soil, then loosen the soil and water.

   Stem nematode disease This disease mainly harms narcissi, and also harms flowers such as tulips, hyacinths, gladioli and primulas. Symptoms of affected flowers: after the leaves are attacked, blister-like spots form, and the plants become dwarfed and bent. Brown ring spots appear on the bulb scales, and diseased bulbs often fail to put out leaves. Control: choose disease-free bulbs for propagation, and burn diseased plants and diseased bulbs. Treat the soil with chemicals, using 0.5 grams of 15% aldicarb granules per pot of flower soil.