What treatment measures should be taken when flowers suffer from nematode disease?
If flowers contract nematode disease, don't panic; simply take appropriate measures and the flowers will quickly bloom normally again.
(1) After flowers contract this disease, nematodes are present in the roots, stems and leaves. When introducing flowers from other places, it is necessary to find out whether nematodes exist in the place of origin, to prevent diseased transmission through plants, cuttings, corms, bulbs, rhizomes and roots.
(2) Nematodes fear high temperatures above 40°C. For suspect planting material such as roots, rhizomes and corms, hot water treatment can be used: soaking in hot water at 50°C for 10 minutes, or at 55°C for 5 minutes. Water temperature and time must be carefully controlled, and the treated material must be heated evenly. Because different flower varieties, different materials and different periods have different heat tolerance, tests should be carried out first to avoid damage.
(3) Different varieties of various flowers differ in their ability to resist nematode disease, so attention should be paid to selecting varieties with strong resistance.
(4) Nematodes are lower animals that like oxygen; they are numerous in the well-aerated surface soil layer (5-30 cm deep), but rare in soil below 1 m; the disease is severe in loose, moist soil; it is severe where the previous crop was a host plant, and mild in virgin soil; it is severe in shallowly ploughed land and mild in deeply ploughed land. Therefore, when cultivating flowers, new soil and new pots should be used as much as possible; for open-field cultivation, the soil should be deep-ploughed and sun-dried several times; for potted soil, it should be sun-dried for several more days, and soil treatment should be carried out when necessary. When using old pots, they can be soaked in 50-100 times diluted formalin solution for 1-2 days. Greenhouses and flower stands should be sprayed with 1000 times diluted formalin.
(5) Diseased plants should be pulled up and burned. Carbofuran can be spread on the soil near the diseased plants. Use about 15 grams of 3% carbofuran granules per sq m, mixing it into the soil while loosening the soil.
(6) For potted flowers with nematode disease, carbofuran can be used for control. The specific method is to evenly scatter 3% carbofuran granules on the soil surface, mix them into the soil while loosening it, and then carry out normal water and fertilizer management. The dosage can be determined according to the inner diameter of the pot rim: for an inner diameter of 15 cm use 1-2 grams, for an inner diameter of 20 cm use 2-3 grams, for an inner diameter of 23 cm use 3-4 grams, and for an inner diameter of 27 cm use 4-5 grams. For woody potted flowers, the dosage can be slightly larger.